IN SCIENCE 
 
 PATTEHSON 
 

STUDIES IN SCIENCE 
 
 FOR 
 
 SEVENTH AND EIGHTH GRADES 
 
 AND 
 
 JUNIOR HIGH SCHOOLS 
 
 ALICE JEAN PATTERSON, B.S. 
 
 TEACHER OF NATURE STUDY AND ELEMENTARY SCIENCE, ILLINOIS STATE 
 NORMAL UNIVERSITY, NORMAL, ILLINOIS 
 
 * Vo o e '' 
 
 CHICAGO NEW YORK 
 
 ROW, PETERSON AND COMPANY 
 
rs 
 
 COPYRIGHT, 1919 
 ROW, PETERSON 
 AND COMPANY 
 
PREFACE 
 
 This book is designed for the seventh and eighth grades 
 of rural and village schools, and for the first book in science 
 in Junior High Schools. Its purpose is to stimulate interest 
 in the simple scientific problems found in daily life, to train 
 toward a correct understanding and truthful interpretation 
 of common objects and phenomena, and to arouse some ap- 
 preciation of the intimate relation that exists, on the one 
 hand, between science and health, and, on the other, between 
 science and economic prosperity. 
 
 The work has grown out of a conscious effort to fit science 
 study to the needs and interests of grammar school children. 
 All the exercises have been used in regular class work in the 
 training school of the Illinois State Normal University. They 
 represent much sifting, rejection, and rearrangement during 
 a period of about ten years. Most of them have had the addi- 
 tional test of the class-room in elementary schools where 
 teachers have used "Outline Lessons in Nature-Study Agri- 
 culture," published by the author five years ago. 
 
 The material is chosen from the immediate environment 
 of the pupils: the home, school, farm, and garden. It is 
 sufficiently agricultural in character to warrant the use of 
 the book as a text in elementary agriculture. While some 
 attention has been given to continuity of subject-matter, the 
 chapters in the main are arranged with reference to seasonal, 
 rather than logical, sequence; biological topics occurring in 
 the fall and spring, physical topics in the winter. 
 
 Part One deals largely with the habits, structure, and uses 
 of domesticated plants, and is followed during the winter by 
 a study of soil and soil-water in their relation to plant growth. 
 In the spring a number of practical farm and garden projects 
 are planned, accompanied by definite scientific studies that 
 look toward some realization of the basic principles and fun- 
 damental laws that govern plant life. 
 
 3 
 
 413117 
 
4 " PREFACE 
 
 Part Two emphasizes, in its biological phases, animal life 
 and projects, but takes up also some of the lower plant forms, 
 and the more difficult problems of plant propagation. The 
 physical studies during the winter are based upon water sup- 
 ply, heating, lighting and ventilating the home and school. 
 In the spring, simple problems of landscape gardening are 
 introduced. 
 
 In order to use the book successfully, teachers should 
 realize that pupils must have a hand-to-hand contact with 
 real objects and phenomena, must deal with actual situations, 
 must come naturally to one problem after another. The les- 
 sons aim to suggest problems, to direct observation, investi- 
 gation, and experiment along lines that foster openminded- 
 ness, promote initiative, and lead to independent effort in 
 the discovery of truth. The discussions and explanations 
 accompanying each study are designed to clear up doubts 
 concerning the more difficult problems and to state facts that 
 may not be found at first hand. 
 
 The author wishes to express her gratitude to the teachers 
 and pupils of the training school in the Illinois State Normal 
 University who made possible the practical working out of 
 these studies in science. Special thanks are due to Mr. Fred 
 Ullrich, Miss Agnes Storie, and Mr. George Cade, for their 
 valuable assistance in testing various phases of the work, and 
 for their interest and advice in the attempt to meet the needs 
 of the boys and girls. 
 
 The author wishes also to acknowledge her indebtedness to 
 Miss Ruby Scott for her careful proof reading, to Miss Evalyn 
 Clark, Miss Frances Augustine, and Mr. Harold F. James 
 for assisting in the preparation of the original illustrations; 
 and to those publishers who have permitted the use of their 
 illustrations. 
 
 ALICE JEAN PATTERSON. 
 
TABLE OF CONTENTS 
 
 PART ONE 
 
 FALL STUDIES 
 
 PAGE 
 
 Chapter I Plant Studies 7 
 
 Chapter II Farm Crops 32 
 
 Chapter III Weeds 67 
 
 Chapter IV Tree Studies 84 
 
 WINTER STUDIES 
 
 Chapter V Soils 95 
 
 Chapter VI Water in Soil 103 
 
 Chapter VII Soil Water and Plants 110 
 
 Chapter VIII The Work of Plants 120 
 
 Chapter IX Food and Health 130 
 
 SPRING STUDIES 
 
 Chapter X Garden Studies and Home Projects. 139 
 
 Chapter XI Farm Crops and Home Projects. . . 176 
 
 Chapter XII Trees ; 189 
 
 PART TWO 
 
 FALL STUDIES PAGE 
 
 Chapter XIII Insects , 201 
 
 Chapter XIV Fungi 228 
 
 Chapter XV Yeast and Bacteria 239 
 
 Chapter XVI Propagating Plants by Cuttings. . . 255 
 
 Chapter XVII Fruit and Fruit Trees 265 
 
 Chapter XVIII Domestic Animals 283 
 
CONTENTS 
 
 WINTER STUDIES 
 
 Chapter 
 Chapter 
 Chapter 
 Chapter 
 Chapter 
 Chapter 
 
 XIX 
 
 XX 
 
 XXI 
 
 XXII 
 
 XXIII 
 
 XXIV 
 
 SPRING STUDIES 
 
 Chapter XXV 
 Chapter XXVI 
 Chapter XXVII 
 
 Light and Lighting 325 
 
 Water Supply 339 
 
 Forms of Water 354 
 
 Heat and Heating 364 
 
 Air 385 
 
 Weather . . 406 
 
 Poultry and Poultry Projects 421 
 
 Birds 436 
 
 Landscape Gardening 451 
 
 Index 476 
 
STUDIES IN SCIENCE 
 
 PART ONE 
 
 FALL STUDIES 
 
 CHAPTER I 
 
 PLANT STUDIES 
 
 Plants are among the most important objects in your 
 environment. They not only add much to the beauty 
 and comfort of your surroundings, but they feed and 
 clothe the world. Everything that you eat, if you 
 omit water and certain minerals that it contains, may 
 be traced directly or indirectly to plants. The same 
 thing may be said about your clothing. Much of the 
 raw material of which it is made comes directly from 
 plants, while the rest is provided by animals that de- 
 pend upon plants for their food. 
 
 Plants are not only important because of what they 
 directly provide, but through them a large proportion 
 of the men and women all over the world earn a live- 
 lihood. Some of you are even now directly interested 
 in gardening or farming. Your garden and farm pro- 
 
 7 
 
g STUDIES IN SCIENCE 
 
 jects, however, will not have their full educative value 
 unless, along with the practical work, you study the 
 plants themselves to find out all you can about their 
 habits of growth, their relation to the soil, their work 
 and their uses. 
 
 1. VEGETABLES 
 
 Material. Vegetables raised in the district. Spe- 
 cial types tomato, squash and pumpkin, potato and 
 sweet potato. 
 
 Study. Make a list of all the different kinds of 
 vegetables that have been grown in your neighbor- 
 hood this season. Classify them with reference to 
 the time they are ready for use: 
 
 1. Spring. 
 
 2. Early summer. 
 
 3. Late summer. 
 
 4. Fall. 
 
 Which ones continue to supply food for the long- 
 est period without replanting? Which are in great- 
 est demand on the market! Which are used most 
 frequently on your home table! 
 
 The tomato. Observe tomato plants and note 
 their habit of growth. What is the position of the 
 stems of an unsupported plant? Describe the leaves. 
 They resemble the leaves of what other garden 
 
PLANT STUDIES 
 
 plants ? For how long a period does the tomato plant 
 blossom and bear fruit? Look for all stages from 
 the unopened flower bud to the mature fruit. 
 
 Fig. 1. 1. A tomato flower showing the slender sepals below and 
 the six-pointed corolla with the stamens clustered at the center. 2. 
 Flower with stamens removed showing the pistil in the center. The 
 round part of the pistil is the ovary. 3. A flower from which the 
 corolla has dropped. The withered stamens and style are still fas- 
 tened to the growing ovary. 
 
 Examine a flower, and name and describe its parts. 
 If you do not know the names, find them in Fig, 1. 
 Compare a number of flowers and determine in what 
 respects they vary. What parts of the flowers fade 
 and drop off? What parts remain and produce 
 fruit! 
 
 Make cross-sections of several green tomatoes and 
 also of a ripe one. How many seed cells or sec- 
 tions do you find! Where and how are the seeds 
 fastened! Compare the fruit of different varieties 
 as to the amount of meat and seeds. Look for dif- 
 ferences among individual plants of the same va- 
 riety as to the number and size of the tomatoes and 
 
10 STUDIES IN SCIENCE 
 
 the quality of the fruit. Choose for seed those that 
 have the characteristics you wish to reproduce next ' 
 year. 
 
 Name all the ways that tomatoes are used for 
 food. How are they preserved for future use? How 
 important are they as an industrial plant? 
 
 Discussion. In your study of the flowers you 
 probably found quite a difference among individuals 
 in the number of se' pals, pet' als and sta' mens. Some 
 of them look as if they were a combination of sev- 
 eral flowers. This, no doubt, has come about by 
 cultivation. Botanists tell us that the flower of the 
 wild plant is simple and that the fruit does not have 
 so many sections. The fruit is an excellent example 
 of a berry. It is the ripened 6' va ry. 
 
 Tomatoes are fast becoming important industrial 
 plants. They are grown in almost every state in 
 the union. In many places large tracts of land are 
 given over to their culture. They are canned in 
 large quantities in canning factories as well as by 
 girls' clubs and in the home. Quantities are also 
 used every year in factories to make catsup, pickles 
 and soup preparations. 
 
 History. The tomato is a native of the warm 
 regions of South America. It was taken to Europe 
 during the sixteenth century, but was not used for 
 food until much later. In United States it was 
 
PLANT STUDIES H 
 
 raised as a curiosity or ornamental plant known as 
 the "love apple" until about 1830. It then began 
 to be used on the table; but its true food value has 
 been recognized only about fifty years. 
 
 Description. The stem is weak and when unsup- 
 ported trails upon the ground. You probably found 
 flowers, the small green berry, the larger one and the 
 ripe fruit on the same plant. ''This is one of the great 
 advantages of the tomato plant, since it continues to 
 blossom and bear fruit until frost kills the plant. The 
 leaves are compound, and they, as well as the flow- 
 ers, are similar to those of the potato. These plants 
 both belong to the Nightshade family. 
 
 Canning tomatoes. If you have never canned any 
 fruit, nothing is easier to begin with than toma- 
 toes. For directions see Harvesting and Canning, 
 page 150. 
 
 THE SQUASH AND OTHEE CUCURBITS 
 
 Material. Growing plants of squash, pumpkin 
 and other relatives as melons and cucumbers. 
 
 Study. No garden plant has more interesting char- 
 acteristics and habits than the squash and its relatives. 
 Observe one of the growing plants. How much space 
 does it occupy? What is the length of the longest 
 branch? Look down upon the plant and determine 
 
12 STUDIES IN SCIENCE 
 
 to what extent the leaves hide the ground. What 
 special adaptations can you find that make it pos- 
 sible for all the leaves to be exposed to the light? 
 Cut a stem in two and describe its structure. What 
 do you find on the stem besides leaves! Describe 
 a tendril. Where are the tendrils attached! What 
 is the use of the tendrils! 
 
 Fig. 2. Portion of a squash plant showing the relation of leaves and 
 
 tendrils. 
 
 Look for flowers. How many kinds do you find? 
 Examine the two kinds carefully, stating how they 
 are alike and how different. Try to make out the 
 special function of each flower. Observe the flowers 
 in the evening. What do they do! 
 
 What insects have you found visiting the flow- 
 
PLANT STUDIES 13 
 
 ers? Look for the place where the nectar is secreted. 
 
 Cut a small green pumpkin or squash across the 
 center. How many distinct sections has it? To 
 what are the seeds attached? Cut a ripe one and 
 note the changes that have taken place. Compare 
 a section of a cucumber with the pumpkin noting 
 resemblances and differences. 
 
 Discussion. The pumpkin, squash, cucumber, melon 
 and gourd belong to a family known as Cucurbitacae. 
 They are often called cucurbits. The entire family 
 is noted for the wonderful growth that the plants 
 make in a few weeks or months. They produce not 
 only long vines and large leaves, but great numbers 
 of large fruit. While these plants have the habit of 
 trailing upon the ground, some "of them are good 
 climbers. The gourd is an example. All of them 
 have tendrils which seems to indicate that perhaps 
 some time in their past history they were all good 
 climbers. Why would some of them not do well 
 as climbers now? 
 
 History. The history of squashes and pumpkins 
 is interesting. Botanists believe that originally they 
 were natives of Asia. Nevertheless, the North Amer- 
 ican Indians raised them in their fields of maize 
 long before the early colonists settled in America. 
 
 You will find it worth while to make a compara- 
 tive study of any other cucurbits that may be found 
 
STUDIES IN SCIENCE 
 
 in your neighborhood, as watermelons, muskmelons 
 and cucumbers. All of these are of Asiatic origin. 
 They were first brought over into Europe and from 
 there to America. The melons thrive best in the 
 South where they have a warm soil and climate. 
 Description. You found two kinds of flowers, each 
 
 with a five-lobed yellow 
 co rol' la and five slen- 
 der green sepals. The 
 one with the peculiar 
 body in the center re- 
 sembling a yellow can- 
 dle is a stam' i nate 
 flower. If you rub your 
 finger over this body, 
 you find it is covered 
 with pol' len. It is 
 made up of the stamens. 
 At the lower part of 
 this you find some slits 
 which open into a shal- 
 low cup. In this is the 
 nectar which attracts 
 bees. This flower is 
 called staminate be- 
 cause it has stamens 
 and no pis' til. 
 
 Fig. 3. 1. Staminate flower of a 
 squash. A, Corolla; B, One sepal 
 (Five of these form the calyx); 2. 
 Staminate flower with corolla and 
 calyx removed to show the stamens. 
 A, Opening into nectar cup; B, Fila- 
 ment; C, Anthers joined to form a 
 knob. 
 
PLANT STUDIES 
 
 15 
 
 The other flower with the ca' lyx and corolla 
 tened to the top of a green body which later be- 
 comes the fruit is the pis' til late flower. Inside the 
 corolla you find the pistil with three short styles 
 each with a stig' ma at the top. The green part be- 
 low is the ovary. This flower also has a nectar cup 
 situated just below the 
 styles.. Both flowers are 
 necessary to produce the 
 seeds, since neither has all 
 the essential organs. 
 
 Bees are usually the car- 
 riers of pollen from the 
 staminate to the pistillate 
 flowers. As the bee enters 
 the opening to get nectar 
 its legs and body become 
 dusted with pollen. When 
 it goes to a pistillate flower 
 it is almost certain to brush 
 against the stigmas and 
 leave some pollen. It is the 
 pistillate flower that always 
 produces the fruit and seeds. 
 In the cross-section of the green fruit you found 
 three curved partitions to which the seeds are at- 
 tached. Later the pulp changes to stringy coarse 
 
 t 
 
 Fig. 4. 1. Pistillate flower 
 of squash. A, Corolla; B, 
 Ovary which develops into 
 squash. 2. Pistillate flower 
 with corolla removed to show 
 pistil. A, Ovary; B, Nectar 
 cup; C, Style; D. Stigma. 
 
16 STUDIES IN SCIENCE 
 
 fibers which allow the ripe seeds to drop out in a 
 mass. 
 
 There are a large number of varieties of squash 
 and pumpkin. 
 
 The hard-shelled squashes and a few pumpkins 
 may be kept > fresh for winter use if they are gath- 
 ered before being frozen and stored in a cool place. 
 They may be successfully canned by the hot water 
 or steam process. Besides their use as human food, 
 pumpkins are used largely as food for cattle. 
 
 Potatoes. Are potatoes in your community raised 
 as farm or garden crops! Are they early or late 
 varieties? At what time are they ready for use? 
 What is the condition of the plants of early pota- 
 toes at this season? Of late potatoes? 
 
 Study. Examine plants that are still green. What 
 is the position of the stems? Describe the leaves. If 
 there are any flowers find their parts. If they have 
 all faded, see if you can discover where they were 
 attached to the stems. Look for fruit. How do you 
 account for the fact that potatoes blossom and yet 
 rarely produce fruit and seeds? 
 
 Carefully remove the soil from a hill. How near 
 the surface are the potatoes or tubers? How far 
 from the center of the hill? Are the roots above or 
 below the tubers? How are the tubers fastened to 
 the main stem? Dig several hills and compare as 
 
PLANT STUDIES 17 
 
 to the number of tubers and uniformity of size. 
 Which hills would you prefer to use as "seed pota- 
 toes " next year? 
 
 If possible, compare different varieties of pota- 
 toes and note differences in color, shape, smooth- 
 ness of skin, number and depth of eyes. Which 
 do you consider preferable for family use? Which 
 may be peeled with the least waste? Do you find 
 scab, rough blotches, on any of the potatoes? What 
 causes scab? 
 
 What methods of harvesting potatoes are em- 
 ployed in your district? Find, if possible, what the 
 yield is per acre. What is a good average yield? 
 What is the current price per bushel? What do 
 you think of potatoes as a paying crop? Which 
 takes the greater amount of labor, the raising of 
 a crop of corn or a crop of potatoes? Which yields 
 the greater profit? 
 
 Name all the uses of potatoes that you know; all 
 the different ways of cooking. How are they stored 
 and kept for future use? See Home Projects, p. 159. 
 
 Discussion. The potato is among our most valu- 
 able garden and farm crops. It is probably used 
 more extensively as food the world over than any 
 other crop except rice. , In the northern states it is 
 an important farm crop; in most other states it is 
 raised as a truck or garden crop. 
 
18 STUDIES IN SCIENCE 
 
 History. The potato is a native of America. It 
 was probably found in South America and Mexico 
 by the early Spanish explorers, who introduced it 
 into Europe. It was soon grown in a number of 
 the European countries. It became so important a 
 crop in Ireland that the name Irish potato was given 
 to it. The early colonists from Europe brought it 
 over into Virginia and New England. It has been 
 greatly improved by cultivation and selection. Great 
 numbers of new varieties have been produced. The 
 wild potato is still found in Chili and Peru. The 
 tubers of this wild plant are very small,, not larger 
 than small marbles. The flowers are abundant and 
 most of them produce fruit and seeds. 
 
 Description. The plant is weak and trailing, a rela- 
 tive of the tomato, which it resembles in leaves, flow- 
 ers and fruit. You have noticed that while the potato 
 has flowers it seldom produces fruit. This habit is 
 probably brought about by cultivation. The food 
 the plant consumes is used to produce large tubers 
 instead of fruit and seeds. The fruit is a small 
 green ball resembling a small tomato. 
 
 You will be interested to know that seeds are 
 used to produce new varieties. If you should plant 
 potato seeds you would get a large number of dif- 
 ferent kinds of potatoes. Most of them would prob- 
 ably be of little value, but among them you might 
 
PLANT STUDIES 19 
 
 find one of such excellent qualities that it would be 
 well worth growing. You could give it a name and 
 after several years when you had grown a large 
 quantity put it on the market as a new variety. That 
 is just what potato breeders have done to produce the 
 different kinds of potatoes. 
 
 Instead of -seeds, the tuber is used to propagate 
 new plants. Much may be done to improve the po- 
 tato crop both in quantity and quality by a careful 
 selection of tubers for planting. You noticed in 
 comparing the hills that some produce a larger 
 number of fair-sized potatoes than others. These are 
 the ones that should be chosen to plant next spring. 
 
 Potatoes are used chiefly as food for the table. 
 They are also used largely in some places for mak- 
 ing starch. They are very nutritious when prop- 
 erly cooked. Baked potatoes are more wholesome 
 than those cooked in any other way. Another method 
 is to boil the potatoes with the skins on. In both 
 these methods certain healthful minerals are retained. 
 
 Potatoes yield on an average about one hundred 
 bushels per acre. Some tracts yield two or three 
 times that quantity. The estimated cost of raising 
 an acre of potatoes is between twenty-five and forty 
 dollars. You can easily calculate the net profit. 
 
 Sweet potatoes. To what extent are sweet pota- 
 toes raised in vour community? What is the habit 
 
20 STUDIES IN SCIENCE 
 
 of growth of the plant? How many branches grow 
 outward from one plant? What is the length of 
 one stem? Describe the leaves. Compare a num- 
 ber of leaves and note variation in shape of blade 
 and lengtii of pet' i die. 
 
 Study. Dig up a plant and observe how the roots are 
 attached to the stem. How many potatoes does one 
 plant produce 1 Get the average of several hills. 
 How greatly do the potatoes in one hill vary in size? 
 Compare a sweet and a white potato, noting dif- 
 ferences. 
 
 Look for flowers. Where are they attached to the 
 vine? Study the parts. Find the seed pods. How 
 many sections in each? How many seeds? What 
 common flowering plant do the flowers, leaves and 
 seeds resemble? 
 
 At what time are the potatoes harvested? What 
 is the yield? How valuable is the crop? What is 
 the current price per barrel or bushel? How are 
 potatoes stored for future use? What is the history 
 of the sweet potato? 
 
 Discussion. The sweet potato is a near relative 
 of the morning-glory. You probably noticed the 
 similarity in the shape of the leaves. The flowers, 
 too, resemble those of the morning-glory. However, 
 in the North flowers are rarely produced. In the 
 South they are common. They are purplish pink 
 
PLANT STUDIES 21 
 
 in color and the corolla is from one to two inches 
 across. The ovary ripens into a four-celled pod 
 very much like that of the morning-glory. There 
 is one seed in each cell. 
 
 History. The sweet potato stands next to the Irish 
 potato as an important garden crop in United States. 
 It is the chief- garden crop in the South. Certain 
 varieties do well in some of the northern states. New 
 Jersey is especially noted for its fine sweet potatoes. 
 
 The native home of the sweet potato is not definitely 
 known, but botanists believe that it originated in 
 tropical America. It reaches its highest development 
 there, where it is a perennial, living year after year 
 producing its roots and seeds each year. 
 
 Description. The sweet potato is a fleshy root, 
 while the white or Irish potato is a tuber, a kind of 
 underground stem. Small branch roots grow from 
 the ends and sides of the sweet potato, but there are 
 no eyes or buds as tkere are on the white potato. 
 The fleshy roots are used to propagate the plants. 
 They are planted early in the season in a hotbed. 
 They send out a large number of sprouts. These 
 are pulled off and set about eighteen inches apart 
 in ridges that have been prepared for them. Some 
 growers set out a few plants and when these have 
 grown stems eight or ten inches long the ends are 
 cut off and set out, thus producing new plants. 
 
22 
 
 STUDIES IN SCIENCE 
 
 2. FLOWERING PLANTS 
 
 Material. Flowering plants of the neighborhood. 
 
 Choose for study several annuals that have single 
 
 flowers, as petunia, nasturtium, California poppy, 
 
 sweet pea, snapdragon or larkspur. Note the habit 
 
 of growth, the characteristics 
 of the stem and the leaves. 
 . Study. Examine a flower. 
 What different organs do you 
 find? What are their names! 
 See Fig. 5. 
 
 What is the function of a 
 flower? What parts are neces- 
 sary in order that seeds may be 
 formed? Look for pollen on 
 the anthers. Where must the 
 pollen be placed in order to be 
 of use in forming seeds ? Find 
 flowers in various stages of de- 
 velopment from those that have 
 just opened to those that are fading. What parts 
 wither and drop off? What ones remain? What 
 develop into fruit and seeds! Study the fruit in its 
 stages of growth. 
 
 What insects do you find on your flowers? Watch 
 patiently to discover what they are doing. Deter- 
 mine, if possible, where the nectar is secreted and 
 
 Fig. 5. Section of a 
 petunia flower. In the cen- 
 ter is the pistil. A, Ovary; 
 B, Style; C, Stigma (at 
 the sides are the five 
 stamens) ; D, Filament; E, 
 Anther, in which pollen is 
 produced. 
 
PLANT STUDIES 23 
 
 to what extent insects must become dusted with pollen 
 in order to obtain it. 
 
 The following outline will be found helpful in the study of flow- 
 ering plants. 
 
 1. Name: 
 
 2. Habit of growth: erect, procumbent, climbing, creeping. 
 
 3. Stem: tall, low, branching, spreading, smooth, hairy, sticky, 
 etc. 
 
 4. Leaves: simple, compound, large, small, hairy, soft, rough, 
 special characteristics that make them attractive. 
 
 5. Flower: a. single, cluster; b. dates of flowering; c. sim- 
 ple description of parts; d. special features. Where is the nectar 
 secreted? Insects that visit the flower. 
 
 6. Fruit: a. kinds; pod, capsule, berry, pappus flyer, etc.; 
 b. seeds: few, many, large, small, special adaptions for distribu- 
 tion. 
 
 7. Remarks: history, family relationship, value for ornamental 
 purposes. 
 
 Filled out for the petunia, the outline will appear in your note- 
 books as follows: 
 
 1. Name: Petunia. 
 
 2. Habit of growth: procumbent and spreading with many erect 
 branches. 
 
 3. Stem: hairy and sticky. 
 
 4. Leaves: simple, vary in size, hairy, sticky, thick. 
 
 5. Flower: a. simple; b. dates of flowering, from June until 
 frost; c. calyx, green, five sepals; corolla, white, purple, or pink, 
 funnel shape, long tube; stamens, five fastened to the tube of the 
 corolla; pistil, one in center with large green ovary, slender style 
 and disk-like stigma; d. nectar is secreted at the base of the 
 corolla tube. Moths and butterflies visit the flowers to get nectar. 
 All parts of the flower wither and fall off except the calyx and ovary. 
 
 6. Fruit: a. formed from ovary, a conical pod or capsul. b. 
 seeds, many and small; pod splits at top and seeds fall out. 
 
 7. History, etc.: The petunia that we know has been produced 
 by the mixing of two species that are natives of South America. 
 One of these had a large white flower, the other a small, reddish 
 purple one. The two species were introduced into Europe some 
 
24 STUDIES IN SCIENCE 
 
 time between 1823 and 1832, and it is from the mixing of these that 
 we get the different colors that petunias show today. 
 
 The petunia belongs to the Nightshade family; hence is a relative 
 of tomatoes and potatoes. 
 
 In a similar way fill out the outline for other flowering plants. 
 You will find some interesting differences among them. For ex- 
 ample, the nasturtium has its nectar secreted in a long spur which 
 is formed from three of the sepals. It has very prominent streaks 
 on the petals which lead do\vn to the nectar. These are called 
 nectar guides. 
 
 The California poppy has its sepals in the form of a green cap 
 which encloses the flower bud. This cap falls off when the flower 
 opens and nothing is left but the little frill to which it was fas- 
 tened. 
 
 The sweet pea has three differently shaped petals in each flower. 
 It is known to botanists as the butterfly flower. Each kind of petal 
 has a name; the broad one at the top is the banner, the side ones 
 are the wings, and the two that are joined together to hold the 
 stamens and the pistil form the keel. Our common beans and peas, 
 the different kinds of clover, locust and red bud trees all have this 
 same kind of flower. The fruit also is similar, a flat pod with seeds 
 on the inside. The pod is called a legume. 
 
 Composite flowers. After you have studied several 
 simple flowers, choose one that has a large number 
 of small flowers crowded together into a head, such as 
 a sunflower, cosmos or gaillardia. 
 
 Examine a sunflower or other head. How many 
 different kinds of flowers do you find? How do the 
 little flowers, or florets, in the center differ from those 
 at the outside? Choose for close observation one of 
 the florets that has two thread-like bodies projecting 
 from the top and ending in a curl. Find all the parts 
 of the flower. How many points has the brownish 
 
PLANT STUDIES 25 
 
 corolla! How many sides has the brown tube at the 
 center. Open up the tube with a pin and see what is 
 on the inside. What are the two curled over threads 
 at the top? To get the names study Fig. 7. What 
 part will produce the seed! Break a head through 
 the center so that you may better see the arrange- 
 ment of the florets. Describe the little bodies that 
 you see sticking up at the base of each little flower. 
 
 Which florets open first! If possible watch a head 
 for a number of days to solve this problem. Examine 
 closely one of the outside flowers. What parts does 
 it lack? Does it produce seed? 
 
 Study a head that has gone to seed. What parts 
 of the florets are left! Count the seeds. What 
 use is made of sunflower seeds? How valuable are 
 they! 
 
 Discussion. The sunflower is an excellent type of 
 a large group of flowering plants both wild and cul- 
 tivated that have a great number of small flowers 
 crowded into a head. All such plants belong to the 
 family Compositae. We usually speak of the flowers 
 as composites. 
 
 Look for other composites among your flowering 
 plants. You will find some interesting differences 
 among them. The zinnia and asters have well devel- 
 oped styles and stigmas in their ray flowers, so they 
 produce seeds as well as the disk flowers. The bracts 
 
STUDIES IN SCIENCE 
 
 in these flowers are fringy and colored and add no 
 
 little beauty to the flowering head. 
 
 Make a collection of all the composites among your 
 
 cultivated flowers. 
 
 Sunflowers are of considerable value in certain 
 
 states, especially 
 Kansas, Nebraska 
 and parts of Mis- 
 souri. The stalks are 
 sometimes used for 
 fuel, while the seeds 
 are used to feed stock 
 and poultry. A very 
 
 Fig. 6. 1. Ray flowers of a zinnia 
 showing the curled stigmas, the style, 
 ovary, and one petal in the corolla. 
 2. A disk flower of the zinnia showing 
 the five-lobed corolla attached to the 
 ovary, and the slender bract at one side. 
 
 good oil resembling 
 olive oil is made from 
 the seeds. An acre of sunflowers yields about sixty 
 bushels of seed. 
 
 Description. The sunflower is a good specimen 
 to study because its parts are so large. The outside 
 florets with the showy petals are known as ray flow- 
 ers, while the small inner ones are disk flowers. The 
 disk flowers have all the organs present, the two 
 parted calyx, the five pointed corolla, the stamens 
 enclosed in a tube and the pistil whose style grows 
 up through the midst of the stamen tube with the 
 two curled stigmas at the top. The ovary is at the 
 very lowest part. The small leaflike bodies that you 
 
PLANT STUDIES 
 
 27 
 
 B... 
 
 Fig. 7. 1. A disk flower of 
 the sunflower in the early stage 
 of blossoming. 2. The same 
 flower in a later stage. A, 
 Ovary; B, Calyx; C, Corolla; D, 
 Anther tube; E, Stigma. 
 
 find attached near the base of the florets are bracts. 
 The same name is given to the over-lapping green 
 bodies that are attached to the underside of the head. 
 This entire group of bracts 
 is called the involucre. It 
 protects the head before it 
 is ready to open up its 
 flowers. 
 
 You probably discovered 
 that the ray flowers do 
 not have either stamens or 
 stigmas; hence they do not 
 produce seeds. They are 
 the showy flowers, how- 
 ever, and probably aid in attracting the insect visitors 
 that transfer pollen from one flower to another. 
 
 The regular arrangement of the flowers and later 
 of the seeds in the head is one of the interesting- 
 features of the sunflow r er. The florets open from the 
 outside toward the center, so you can find in the 
 same head all the stages from those that are begin- 
 ning to wither at the outside to the unopened buds 
 in the center. 
 
 Perennials. Look among your perennial flowers 
 for composites. Make a list of all the perennials 
 that blossom in the fall. What parts of these plants 
 live over winter? Why are they called perennials! 
 
28 STUDIES IN SCIENCE 
 
 Perennials may be used even more than annuals to 
 make your home grounds attractive. By making 
 careful selection you may have perennials flowering 
 from early spring until heavy freezes in the northern 
 states and all the year around in the southern states, 
 
 3. WILD FLOWEKS 
 
 Study. What wild flowers are in blossom now? 
 Where do you find them? What different colors do 
 you find among them? Are they annuals or peren- 
 nials? Look at a number to determine whether they 
 have simple or composite flowers. 
 
 Make a detailed study of golden-rods. Use the 
 outline suggested for annual flowering plants. Both 
 golden-rods and asters are composites. The heads 
 of the golden -rod are very small and are arranged 
 together at the top of the branches, thus giving the 
 beautiful feathery appearance to the cluster. You 
 will find that they have both disk and ray flowers. 
 Small as the flowers are you can see that both kinds 
 produce seeds. 
 
 Watch the changes that take place as the flowers 
 fade. What is the color of the heads when all have 
 gone to seed? What gives them their fluffy, feathery 
 appearance? What adaptation have they for scatter- 
 ing their seeds? Look for different species of golden- 
 
PLANT STUDIES 29 
 
 rod. Make a detailed study of asters and other wild 
 flowers. If you cannot go to the fields to watch the 
 changes that take place in these flowers, place a few 
 sprays of each in jars of water indoors. They will 
 continue their development here. Another reason 
 for doing this is that golden-rods and asters are 
 almost as beautiful after the flowers have faded, with 
 their gray, fluffy seed heads, as they are when in full 
 bloom. Even after the seeds with their hairy para- 
 chutes have flown away, these plants are still attract- 
 ive with their dark brown stems and silvery white 
 disks. In order to appreciate the beauty of the land- 
 scape during the fall and winter, these should be 
 observed in the fields and along roadsides with other 
 plants. 
 
 A few of these wild plants mixed in with your 
 perennial border in the garden will add much to its 
 attractiveness. You can grow them either from seeds 
 or roots. 
 
 Discussion. While you are studying flowers both 
 annual and perennial observe carefully the different 
 shades and colors and determine which ones look 
 well growing side by side. You can plan color 
 schemes for flower projects much easier in the fall 
 and summer when you see the flowers themselves, 
 than you can in the spring when you have nothing 
 but seed catalogues to depend upon. 
 
JO STUDIES IN SCIENCE 
 
 While you grow your flowering plants in order to 
 derive pleasure from their beauty, it is well to re- 
 member that, as far as the plants themselves are 
 concerned, their flowers exist not for us but to pro- 
 duce seeds. Scientists tell us, although it has not 
 been proved conclusively, that the bright colors of 
 flowers help to bring insects to them. 
 
 It is certain, of course, that the nectar is secreted 
 to attract insects. All this is done so that pollen may 
 be transferred from the anthers to the stigmas. The 
 stamens, which produce the pollen, and the pistils are 
 the essential organs of the flower. When you study 
 botany you will learn in detail about the wonderful 
 process that takes place in the making of a seed. 
 The following paragraphs give only a brief discus- 
 sion of this process. 
 
 The making of a seed. The first step is the trans- 
 fer of pollen from an anther to a stigma. This is 
 called pollination. The transfer of pollen from an 
 anther to a stigma of the same flower is self-pollina- 
 tion. Cross-pollination is the transfer of pollen from 
 the anther of one flower to the stigma of another 
 flower of the same species. 
 
 The pollen is formed in the anther and when it is 
 ripe the anther bursts open and it comes to the out- 
 side. The stigma is the part of the pistil that is 
 prepared to receive the pollen. When it is ripe or 
 
PLANT STUDIES 31 
 
 ready for the pollen it lias a sticky secretion on it, 
 so that if a grain of pollen falls upon it or is brushed 
 from the hairs of an insect it holds this fast. The 
 little grain then germinates and produces a tube- 
 like structure called the pollen-tube. This grows 
 downward through the style to the ovary. 
 
 In the pollen-tube two cells are found, called sperm- 
 cells. In the ovary is an egg-cell. When the tube 
 reaches the -ovary one of the sperm-cells unites with 
 the egg-cell and forms a new cell. This union is 
 known as fertilization. 
 
 The new cell is the beginning of the seed. It grows 
 rapidly for a time, then stops growth, becomes dry, 
 and we say the seed is ripe. When you find a great 
 number of seeds in a pod it means that there was a 
 pollen grain and an egg-cell for every seed that was 
 formed. 
 
 Bees, moths and some wasps aid plants by carry- 
 ing pollen from one flower to another and thus help 
 to insure the production of seed. 
 
CHAPTER II 
 
 FARM CROPS 
 
 > 
 
 1. COKN 
 
 Material. A cornfield in the community; an entire 
 corn plant including the root system. This should 
 be removed from the ground while the leaves are still 
 green. If it is kept in the basement of the school- 
 room or other cool place, it will dry slowly and may 
 be used for study any time during the year. Provide 
 also a number of ears of different varieties of corn 
 including several small, unripe ears. These should 
 be removed from the stem when two or three inches 
 in length. They may be preserved indefinitely in a 
 jar of alcohol or four per cent formalin. 
 
 Field study. Select a plot ten hills square either 
 in your own plot or in a portion of a large cornfield. 
 What is the distance between the rows? Between 
 the hills? How many stalks in a complete hill? How 
 many hills with one stalk? With two? How many 
 missing hills? What is the actual number of stalks 
 in the plot? What would be the number if each hill 
 had three stalks? What percentage of a perfect 
 
 32 
 
FARM CROPS 
 
 33 
 
 stand does the plot show ? How many stalks have one 
 good ear? Two! How many stalks are barren? 
 How many with smut? With suckers? (A sucker is 
 a small stalk branching from the main stem close 
 to the ground. It never bears a good ear, and there- 
 fore uses up food with little profit.) 
 
 How much greater would your yield be if you had 
 a perfect stand with one good ear on each stalk? 
 
 THE COKN PLANT 
 
 Roots. Notice the root system. How many dis- 
 tinct kinds do you find? Describe the main roots 
 
 MI m 
 
 Fig. 
 
 Eoot system of a corn plant. 
 
 as to number, size and branching. What is their 
 direction of growth? If you have access to a corn- 
 field, dig carefully around a plant to find the rela- 
 
STUDIES IN SCIENCE 
 
 tion of the roots to the soil. How near the surface 
 are they! How deep do they grow! How far out 
 from the hills ? How far between the rows ! 
 
 Where are the brace roots! How many joints on 
 the stem produce these roots! Examine a number of 
 
 plants and 
 report on 
 the greatest 
 
 number of joints bearing brace 
 roots. Do they all succeed in 
 reaching the ground! What is 
 the function of these roots! 
 
 Stem. What is the height of 
 the stem! To what extent do 
 plants vary in height ! How thick 
 is the stem! Measure it near the 
 base and again just below the tas- 
 sel. What is the difference f How 
 many joints, or nodes, in one 
 stem! Where are they closest 
 together! What is the ad- 
 vantage of this ! 
 With a sharp knife cut a stem into small sections. 
 How many different structures do you find in a cross- 
 section! Describe them. Make a longitudinal section 
 and describe what you find. 
 
 Leaves, Count the leaves on one plant. Where 
 
 V 
 
 Fig. 9. A shoot 
 si J owing a row of 
 pistillate flowers. A, 
 Ovary; B, Style. 
 
FARM CROPS 35 
 
 are the longest ones? The shortest! Where and 
 how are they fastened to the stem? What are the 
 parts of one leaf? The lower part that wraps 
 around the stem is called the sheath. The long 
 slender part is the blade. Is the sheath open 
 or closed? What part of the blade is longer, the 
 middle or the margin? What advantage do you see 
 in this wavy margin? Examine the plant where it 
 is hinged to the sheath and describe what you see. 
 What is the chief work of the leaves? 
 
 Flowers. What do you find at the top of the 
 stalk? Do you know what the tassels really are? De- 
 scribe them. Which do they resemble more, heads of 
 wheat or of oats? Carefully remove the husks from 
 a very small ear, one that has just started to grow. 
 Trace the silk down to the cob. What do you find 
 here? See Fig. 9. 
 
 Ear. Where is the ear attached to the stalk? How 
 long is the shank or stem? Remove the husks. To 
 what are they attached? Compare the outer with 
 the inner ones. What do you find on the outer ones 
 that leads you to believe that husks are modified 
 leaves? In what condition do you find the silks on 
 a mature ear? How many rows of kernels are there 
 on one ear? Count them on several and get the 
 average. Is the number odd or even? How do ker- 
 nels at the tip and butt differ from those on the other 
 
36 
 
 STUDIES IN SCIENCE 
 
 parts of the ear? What is the number in one row? 
 
 If you discard the small kernels at the tip and butt 
 
 how many will one ear furnish if used for seed? 
 
 How many hills will it plant if you use three grains 
 
 in each hill? 
 
 Selection. In se- 
 lecting seed, con- 
 sider the entire 
 plant as well as the 
 ear. Visit a corn- 
 field and select 
 plants from which 
 to choose seed. 
 Look for the fol- 
 lowing points: 1. 
 An erect, strong, 
 well formed stalk 
 growing in a hill 
 with two others. 2-. 
 Well developed 
 brace roots. 3. A 
 plant free from 
 smut and suckers. 
 4. The ear situated 
 a little above the 
 middle point of the 
 stalk. 
 
 Fig. 10. A, A well shaped and well filled 
 ear; B, A perfect tip; C, Kernels well filled 
 to the tips, wedge shape so that no space 
 is lost; D, A well filled butt. 
 
FARM CROPS 37 
 
 In choosing seed corn the chief object that a farmer 
 has is the yielding qualities. 
 
 Examine a number of ears and determine what 
 characteristics they have that will make them pro- 
 duce a good yield next year. You will no doubt have 
 the following points: 
 
 1. Shape: An ear that is cylindrical will have more kernels 
 than one that tapers too much at the tip. 
 
 2. Size: (a) length, (b) circumference. An ear of good 
 length and width will, of course, yield more corn than a smaller ear. 
 
 3. Rows: The rows should be close together so there will be 
 no waste space. 
 
 4. Tips and butts should be well filled out. 
 
 5. Shape of kernels: (a) Wedge-shaped grains have little 
 space between the tips at the cob; (b) a deep grain. 
 
 These are the chief characteristics that make an excellent yielding 
 ear. There are tw r o other points, however, that must be given con- 
 sideration. 
 
 6. The ear must be well matured, not soft and flabby. 
 
 7. The color of the ear should be true to the special variety of 
 corn. There should be no mixing of colors or grains; white corn 
 should have a white cob, yellow corn a red one. 
 
 If you were arranging a sample of ten ears for a 
 corn contest according to these seven points, you 
 should have the ten ears as uniform as possible in 
 shape, size, color, etc. 
 
 Value. How valuable is the corn crop in your 
 neighborhood? What is the average yield? The cur- 
 rent price per bushel! Look in your geography to 
 determine how corn ranks among grains raised in 
 United States. What states are included in the "Corn 
 Belt"? 
 
38 STUDIES IN SCIENCE 
 
 Uses. Write a list of all the uses of corn that you 
 know. Make a collection of com products. Put them 
 into small bottles or vials and mount on stiff card- 
 board. Make a collection also of as many different 
 species and varieties of corn as possible. 
 
 Discussion. No doubt you have discovered in your 
 study of the corn plant that it resembles grass in 
 some of its characteristics. In fact, it belongs to the 
 Grass family. It has fibrous roots which grow in all 
 directions frequently reaching at maturity a depth 
 of from three to four feet. The brace roots help to 
 hold the corn erect. 
 
 Stem. The cross-section of the stem showed the 
 outside woody part which gives it strength, and the 
 white pith on the inside with the threadlike fibers 
 scattered through it. These are called fibro-vascular 
 bundles. They are really little systems of canals 
 which carry water and other raw material from the 
 roots to the leaves, and digested food from the leaves 
 back to the stem, roots, seeds, or wherever ft may 
 be needed. 
 
 Leaves. The chief work of the leaves is to manu- 
 facture food for the entire plant. You have already 
 observed that the leaf surface on one plant is very 
 great. This makes possible the manufacture of vast 
 quantities of food so that growth may be very rapid. 
 The wavy margin prevents the long leaves from being 
 
FARM CROPS 
 
 39 
 
 torn in the wind. The projection that you found 
 at the hinge between the blade and the sheathe is 
 called the rain guard. This keeps the water during 
 rains from pouring down between the sheathe and 
 stem. Moisture here would probably result in the 
 growth of mold or mildew. 
 
 Flowers. The tassels and small shoots with the 
 silks are the corn flowers. -They do not have all the 
 parts of ordinary flowers, but 
 they do have the essential 
 parts. If you have ever seen 
 a corn plant just after the tas- 
 sels have opened, you have 
 noticed the yellow powder or 
 pollen scattered upon the 
 leaves and even on the ground. 
 If you looked at the tassel 
 closely you saw the stamens 
 that produced the pollen 
 dangling from each of the little 
 side branches, the spikelets. 
 Since the little flowers of 
 the tassel produce only the 
 stamens, they are the stami- 
 nate flowers. The tiny shoot 
 that becomes the ear has rows 
 of round bodies each with , a 
 
 Fig. 11. 1. The pistil- 
 late flower of corn. A, 
 The glumes that produce 
 the chaff when the corn is 
 ripe; B, The ovary which 
 produces the kernel; C, 
 The style or silk; D, The 
 stigma. 2. The stigma en- 
 larged to show the hairs 
 that catch the pollen. 
 
40 
 
 STUDIES IN SCIENCE 
 
 silk fastened to it. These are- pistils. The round 
 body is the ovary and the silk is the style. This 
 is the pistillate flower because it bears pistils and 
 no -stamens. Both kinds of flowers are necessary to 
 produce the seed. 
 
 Germination. First pollination takes place ; that is, 
 a grain of pollen settles upon the stigma, which is the 
 end of the silk. If the pollen comes from the tassel 
 of the same plant, wo say the flower is self-pollinated 
 
 If it comes from another 
 plant the flower is cross- 
 pollinated. Most corn in 
 our fields is cross-polli- 
 nated. The wind, which is 
 the chief carrier, trans- 
 fers the pollen from one 
 plant to another. 
 
 The pollen grain on the 
 silk germinates and forms 
 the pollen tube, which grows downward through the 
 entire silk until it reaches the ovary. In it are two 
 sperm cells, so small that you would have to have a 
 microscope of high power to see them. When the 
 cells reach the ovary, it is ready to receive them. In 
 fact, it. has been getting ready for them while the 
 tube has been growing through the silk. In it are 
 two important cells also. One of these is called the 
 
 Fig, 12. 
 corn. A. 
 
 Staminate flovrcr of 
 The stamens as they 
 
 hang to shed the pollen; B. The 
 leaf-like glumes. 
 
FARM CROPS 41 
 
 egg-cell, and the other the en' do sperm cell. One of 
 the sperm-cells from the pollen tube unites with the 
 egg-cell to form a new cell. This has the power to 
 grow until it forms a little plantlet which we call the 
 germ or em' bry 6 part of the corn grain. The union 
 of this sperm-cell with the egg-cell in the ovary is 
 called fertilization. This must always occur before 
 the germ or embryo can be formed. 
 
 The second pollen tube cell unites with the endo- 
 sperm cell of the ovary and the resulting new cell 
 grows into the large starchy part of the corn kernel, 
 which is called the endosperm. This is simply a store- 
 house of food placed around the little germ to supply 
 it with nourishment while it is developing its first 
 roots and leaves. It is because of the fact that plants 
 in this and similar ways store so much nourishment 
 in their seeds to furnish food for the little embryo 
 that seeds are so valuable as food for men and 
 animals. 
 
 As the seed germinates and grows the endosperm 
 is used up. By the end of the season it has disap- 
 peared; but the embryo grows into a new plant. Just 
 what kind of plant it will be and what kind of corn 
 it will produce depend largely upon the character of 
 the plants that produced the pollen grain and the 
 ovary cell that united to form the beginning of the 
 seed. You can easily see from this why the charac- 
 
42 
 
 STUDIES IN SCIENCE 
 
 teristics of both plants are so important and why corn 
 growers should select for seed ears as nearly perfect 
 as possible, grown upon plants of the kind they wish 
 to produce. If it is desired, a detailed study of the 
 grain may be made at this time instead of in the 
 spring. See Fig. 30. 
 
 Selecting and storing seed. The best time to se- 
 lect seed corn is early in the fall before heavy frosts, 
 and the best place is in the field, not in the crib. You 
 
 Fig. 13. Seed corn rack. 
 
 have already discovered the important characteristics 
 to consider in choosing corn for seed. After the seed 
 is selected comes the question of storing it for the 
 winter. Certain conditions are essential for keeping 
 the seed corn: 
 
FARM CROPS 43 
 
 1. The atmosphere should be dry. 
 
 2. The temperature should be even and not too 
 cold. 
 
 3. The ventilation should be good. 
 
 A simple method is to tie a number of ears together 
 and hang them up in some convenient place such as 
 an attic, dry shed, or an unused room. Agricultural 
 colleges have suggested a number of methods. See 
 Fig. 13. 
 
 Uses of corn. Corn is used most extensively as 
 food for stock. Not only is the grain used, but also 
 the stem and leaves as green or dry fodder, the whole 
 plant in silage, the bran in ground feed, and the germs 
 in corn-oil ca^e. 
 
 Corn also furnishes a large supply of human food 
 in the form of corn-meal, breakfast foods, hominy, 
 corn starch, syrup and oils. 
 
 Corn oil is manufactured into rubber from which 
 boots, shoes, tires, linoleums and oilcloth are made. 
 It is used also in the manufacture of soap and in the 
 mixing of paints. The cellulose from the stem is 
 used to a slight degree in the manufacture of paper. 
 The cobs are used in the manufacture of pipes and 
 also for fuel. Even the stalks are used for fuel in 
 some of the western states. 
 
 History. Corn is a native of the New World. The 
 Indians called it maize. Its original home was prob- 
 
44 
 
 STUDIES IN SCIENCE 
 
 ably in Mexico or South America. When America 
 was settled by the colonists, corn had already been 
 domesticated by the Indians, who taught the white 
 man how to grow it. 
 
 Types. There are six important species of maize.* 
 The most valuable variety is Dent, which is our com- 
 mon field corn. It gets its name from the dent in the 
 
 THE SEVEN SPECIES OF CORN 
 
 7r 
 
 M 
 
 Fig. 14. Seven species of corn. 
 
 crown of the grain. There are many varieties of Dent 
 corn including all the white and yellow as well as the 
 red and mixed colors. 
 
 Flint corn has a smaller ear than Dent, with from 
 eight to twelve rows of kernels. The grains are 
 smooth and hard. This corn is used largely as fod- 
 der and silage. It is the chief corn grown in the 
 
 northern tier of states. 
 
 *A new type, the branch corn, has been developed, but as yet has 
 no commercial significance. 
 
FARM CROPS 45 
 
 Sweet corns are known by their wrinkled grains 
 and their large percentage of sugar. As green corn 
 they are used largely for human food. It is said that 
 the first sweet corn cultivated in America was secured 
 from the Susquehanna Indians in 1779. 
 
 Pop corn is characterized by its small grains and 
 its power to turn wrong side out when heated. When 
 corn pops, the moisture in the grain vaporizes and 
 expands. It is held in by the hard covering which 
 at last explodes. 
 
 Pod corn is rarely seen. It is raised chiefly as a 
 curiosity. Each grain is enclosed in a little husk or 
 pod of its own. The entire ear is also inclosed in 
 husks. This is of interest because it is supposed to 
 be the original type of corn from which all the others 
 have sprung. 
 
 Soft varieties of corn are raised only in southern 
 regions. The mummy corn of Chile and Peru is said 
 to belong to this group. 
 
 2. WHEAT* 
 
 Material. Specimens of entire wheat plants, sam- 
 ples of grains, collection of wheat products, plates or 
 boxes for germination tests. 
 
 *Note. Wheat and other farm crops that provide food or clothing 
 may be studied with profit either in the city or country. While the 
 lessons are suggested for the fall, they may be used equally well 
 in the spring in regions where spring wheat is grown. Since in 
 
46 STUDIES IN SCIENCE 
 
 Study. Make a list of the different foods that are 
 made from wheat. Look at labels on boxes of cereals or 
 breakfast foods, macaroni, etc. What different kinds 
 of wheat flour do you know! How do breads made 
 from these differ? Begin at once to make a collec- 
 tion of wheat products. Place them in small vials, 
 label and fasten by means of fine wire to a sheet of 
 stiff cardboard. A chart showing heads and grains 
 of different varieties of wheat will also be of interest. 
 
 The wheat plant. Examine a wheat plant. -De- 
 scribe the roots. How tall is the stem? Break it 
 and describe the inside. How are the leaves fastened 
 to the stem! How many distinct parts to each leaf? 
 
 The head. We call this kind of flowering head a 
 spike. Each of the branches is a spikelet. How many 
 spikelets in a spike? Count the number in each head 
 and get the average. How many divisions in one 
 spikelet? How many grains? If you have more than 
 one variety of wheat compare them as to the number 
 of spikelets and grains. Estimate -the whole number 
 of grains in one head. Carefully pull to pieces what 
 is left of the flower inclosing the grain. Each small 
 
 many places the study of the plant must be made at a time when 
 field study is impossible, every school should have as a part of its 
 equipment a number of specimens of entire wheat plants. They 
 may be kept from year to year by tying them into small bundles 
 and hanging them up. It will add to the profit of the study if sev- 
 eral varieties are used. There should be at least one specimen of 
 bearded and one of beardless wheat. 
 
FARM CROPS 47 
 
 leaflike body is a glume. If the wheat is a bearded 
 variety, note to what the beard or awn is attached. 
 
 The grain. Examine a grain and write down 
 everything that you see. Determine which end of 
 the grain was fastened to the stem. How deep is the 
 crease in the grain? Compare dry grains with those 
 that have been soaked over night, noting differences. 
 Split open a dry grain. What do you find on the 
 inside? Open a soaked grain and compare with the 
 dry one. What part of the grain is used in making 
 pure wheat flour? Whole wheat flour? Bran? What 
 part produces the new plant? 
 
 Purity test. Spread a small handful of wheat on 
 a piece of white paper. Now separate the weed seeds 
 and other foreign objects from the grain. Put the 
 wheat in one pile and the foreign matter in another. 
 Estimate about what proportion is pure seed. If you 
 have a pair of balances, weigh each and get exact 
 per cent of purity. If you find weed seeds, deter- 
 mine if possible what kind they are. This is a good 
 time to refer to your weed list, which you will find 
 on page 77. 
 
 Germination test. If you are planning to sow 
 wheat, you should make a germination test. To do 
 this, take one hundred grains from a sample of seed 
 wheat. Place moist sand or soil in a dinner plate 
 or shallow box. Scatter the seeds on the surface of 
 
48 STUDIES IN SCIENCE 
 
 the sand not allowing any two to touch each other. 
 With your finger gently press each grain so that it 
 will rest firmly in the sand, but do not cover it. Turn 
 another plate over this one to keep the moisture in. 
 Set it away in a warm place. 
 
 Watch for the germination of the seeds. How 
 long after the planting before the first small sprouts 
 appear! Watch them from day to day until you 
 are certain that no more grains will sprout. By 
 counting the grains that have sprouted, you will 
 be able to determine at once the per cent of germi- 
 nation. If you sowed only the usual quantity per 
 acre, what percentage of a perfect stand would you 
 expect to get from the tested seed! 
 
 Study. Examine one of the sprouted grains. From 
 what part do the roots grow! How many roots 
 are there? Where does the shoot appear! Which 
 grows more rapidly at first, the roots or the shoot? 
 
 Plant some wheat in a box, keep it moist and watch 
 the growth of the plants. If you have a school gar- 
 den or a small plot on the school grounds that may 
 be used, plant some out-of-doors and watch it at inter- 
 vals all fall and winter. What change takes place 
 in the habit of growth when it is about six weeks 
 old? What advantage is it to the plant to spread 
 out rather than to grow erect? To what extent do 
 the plants remain green over winter? Explain why 
 
FARM CROPS 49 
 
 a vast amount of snow is a benefit to the wheat crop. 
 
 What enemies has wheat? How may they be com- 
 bated? The Hessian fly and the chinch bug are among 
 the worst insect foes. Eust and smut are common 
 fungous diseases. 
 
 Discussion. From your observation you find three 
 distinct parts to each grain of wheat; the covering, 
 or hull from which bran is made, the starch which 
 constitutes most of the white flour, and the small 
 dark body, the embryo. The embryo is the little plant 
 that develops its root and shoot when the seed is 
 kept sufficiently warm and moist. The starch fur- 
 nishes food for the growing plant. In whole-wheat 
 flour the embryo and the inner covering of the grain 
 are used as well as the starch. Graham flour is a 
 mixture of finely ground bran and ordinary flour. 
 
 Varieties of wheat. "Wheats are divided into spring 
 and winter varieties. Winter wheats are planted 
 in the fall and live through the winter beginning their 
 growth again in the spring. Spring wheat, as the 
 name indicates, is planted in the early spring and 
 matures its grain the first season. 
 
 There are hard and soft varieties of both spring 
 and winter wheat. Winter wheats are preferred in 
 all regions where the extremes of temperature are 
 not too severe for them, because they yield more 
 than spring wheats. They are ready to harvest ear- 
 
50 STUDIES IN SCIENCE 
 
 Her, and are better able to withstand attacks of 
 insects and fungous diseases. Almost two-thirds of 
 all the wheat grown in the United States is winter 
 wheat. 
 
 Kansas and Nebraska are the centers for the hard 
 winter wheat; the middle western states raise semi- 
 hard wheat; while the southern states raise both 
 semi-hard and soft. The great wheat regions of the 
 North, Minnesota and the Dakotas, raise hard spring 
 wheat. 
 
 There are a great many different varieties of all 
 these kinds of wheat. You may be interested to 
 know how new varieties are obtained. There are two 
 ways. Perhaps some of you have noticed in walking 
 through a wheat field that here and there a few 
 heads seem somewhat different from the rest. Wheat 
 is likely to have "sports," or variations. That is 
 why these plants differ from others though grown 
 from apparently the same kind of seed. Breeders 
 who wish to obtain new varieties select one of these 
 heads that seems to have good characteristics. They 
 save the seeds and plant them in a small plot by 
 themselves. If during the first year the good char- 
 acteristics seem to persist, (he seed from this small 
 plot is preserved and planted on a larger plot. In 
 a few years there is enough seed to plant a number 
 of acres. If the variety proves valuable, the breeder 
 
FARM CROPS 51 
 
 gives it a special name, and a new variety of wheat 
 is soon on the market. This is called the "selection 
 method. 77 
 
 A second method is by means of "cross pollina- 
 tion. 7 ' Wheat does not cross pollinate naturally as 
 corn does. This is because the flower is so arranged 
 that the pollen does not escape but falls upon the 
 pistil of the same flower. If breeders wish to cross 
 pollinate wheat, they must do it by hand. This is 
 a kind of work that requires special training and must 
 be done by experts. The stamens of one flower are 
 carefully removed and on the pistil of this flower 
 pollen from the flower of a different variety is placed. 
 In this way characteristics of the two plants are 
 mingled in the new seeds that are formed, and a 
 new variety may be produced. 
 
 Planting wheat. What methods of planting or 
 sowing wheat are employed in your district! If 
 possible visit a farm and examine a drill and a broad- 
 cast seeder. The drill plants the wheat in rows about 
 eight inches apart. The seeder scatters it broad- 
 cast over the field. In the early days farmers sowed 
 wheat broadcast by hand. 
 
 Value of the wheat crop. How many farmers in 
 your district raise wheat? What is the average yield 
 per acre! What is the price per bushel? How im- 
 portant is the wheat crop in United States? About 
 
52 STUDIES IN SCIENCE 
 
 one-fifth of all the wheat raised in the world is pro- 
 duced in United States. This amounts annually to 
 something over 700,000,000 bushels. With the help 
 of your geography locate the wheat regions of our 
 country to find out what large cities owe their pros- 
 perity to the manufacture of wheat into flour and 
 other products. Besides the grain the straw is of 
 value as food for cattle and horses. The yield of 
 wheat varies greatly in different localities. Some 
 fields yield as low as fifteen bushels per acre. Others 
 yield fifty and sixty. 
 
 Wheat project. If you live in a region where wheat 
 is an important crop, you may be interested in start- 
 ing a plot of your own. Follow the directions for 
 
 planting oats, page 183. 
 
 / 
 
 3. GKASSES AND LEGUMES 
 
 Material. Grasses and clovers found in the com- 
 munity, specimens showing roots, collections of leaves, 
 flowers, and seed heads, for study and booklets. 
 
 Study. Name all the different places in your 
 neighborhood where grasses of some kind are grow- 
 ing. To what extent do you find roadsides, vacant 
 lots and railroad right-of-ways covered with grasses? 
 
 Meadow grasses. What grasses do you find in 
 meadows? Does one grass constitute the entire 
 
FARM CROPS 53 
 
 meadow or is there a mixture of plants! Examine a 
 timothy plant. What is its habit of growth? Does 
 it grow in chimps or spread evenly over the ground! 
 Dig down to the roots. Describe them. How deep 
 do they go! Describe the leaves; the flowering head. 
 Which does it resemble more, a head of wheat or one 
 of oats! What is timothy used for! When is it har- 
 vested! How is it kept for future use! What other 
 meadow grasses are grown in the community! Com- 
 pare them with timothy noting resemblances and 
 differences. If timothy is not grown in the region 
 where you live, choose your chief meadow grass and 
 study it using the topics suggested for timothy. 
 
 Pasture grass. What is the chief pasture grass 
 in your district! Study the habits of growth, espe- 
 cially the underground parts. See outline for blue- 
 grass, page 452. What characteristics make a good 
 pasture grass! Are timothy and blue-grass peren- 
 nials or annuals! What annual grasses are grown 
 in your neighborhood! For what purposes are they 
 used! 
 
 Wliat is the value of timothy hay per ton! What 
 is the average yield in tons per acre! 
 
 Clovers. How many kinds of clover grow in your 
 district! Examine a red clover plant. How many 
 stems do you find in the loose rosette! Where do 
 you find the youngest shoots! What is the advan- 
 
54 STUDIES IN SCIENCE 
 
 tage to the plant of growing close to the ground? 
 Describe the leaves. Look at the leaflets after sun- 
 set; what change in position do they take! Study 
 the flowers. Decide whether the clover head is a 
 single flower or a cluster. How many flowers in one 
 head! Which open first, those at the lower or upper 
 portion of the head! Look closely at one small 
 flower. What common garden flower does it resem- 
 ble! Where is the nectar secreted! What insects 
 are commonly found feeding upon it! Find a with- 
 ered head and look for the seeds. How many seeds 
 does each small flower produce! What shape are 
 the seeds! 
 
 Dig up a clover plant. If the soil is very hard 
 and dry, water it thoroughly the preceding day. 
 Describe the root. What is the advantage of its 
 great length and thickness! Which remains green 
 longer during a summer drought, clover or grasses! 
 Why! Look carefully on the roots for small round- 
 ish bodies about the size of pin heads. These are 
 called tubercles or nodules. On what part of the 
 root are they most numerous! Count the nodules 
 on one small root. What are these nodules and why 
 are they on the roots! 
 
 How many crops of clover are harvested in one 
 season! Which crop usually produces seed! What 
 is the price of the seed! How valuable is clover 
 
FARM CROPS 55 
 
 hay? For what other purpose than to feed stock 
 is clover grown? When and how is it planted? 
 
 Find other clovers and compare with red clover as 
 to habit of growth and uses. How does white clover 
 spread? Why is it a better pasture than meadow 
 grass? What characteristics have all clovers in 
 common ? 
 
 Fig. 15. Harvesting alfalfa. 
 
 Sweet clover. Make a study of sweet clover using 
 the above topics. Which does it resemble more, red 
 clover or alfalfa? How many of the farmers in your 
 district raise sweet clover? What is the length of 
 life of a sweet clover plant? 
 
 Alfalfa. Describe an alfalfa plant. How many 
 main stems has it? Does it grow more or less erect, 
 than red clover? Compare the leaves with those 
 of clover noting resemblances and differences. How 
 do the flowers differ from those of clover? In what 
 
56 STUDIES IN SCIENCE 
 
 are they similar? What kind of a root has it! Look 
 for nodules. To what extent is alfalfa raised in your 
 community! How many crops does it produce in 
 one season! How does it compare with clover as a 
 forage crop! 
 
 Soy-beans and cow-peas. If these plants are grown 
 in your district, study them noting how they grow 
 and what kind of leaves, fruit and seeds they have. 
 Determine whether or not the roots have nodules. 
 What use is made of these plants! 
 
 Discussion. Grasses and legumes are important 
 forage crops providing a large per cent of the food 
 of domestic animals. They are classified with ref- 
 erence to methods of feeding into meadow, pasture, 
 and soiling crops. In pastures animals help them- 
 selves to the growing plants. Meadows are cut, the 
 plants air dried or cured, and stored as hay for future 
 use. Soiling crops are cut green and immediately 
 fed to the animals. 
 
 Blue-grass is the most important pasture grass in 
 the northern states. Frequently white clover is mixed 
 with it. In the southern states Bermuda is the chief 
 pasture grass. The characteristics that make these 
 desirable pasture plants are: 1. They form a thick 
 sod that stands trampling and crowds out weeds. 
 
 2. They have fine blades that stock like to eat. 
 
 3. They are hardy and able to endure extremes of 
 
FARM CROPS 57 
 
 cold or drought. The first and third characteristics 
 are due to their method of spreading by the under- 
 ground stem or rootstock. 
 
 Timothy is the chief meadow grass. Redtop, mea- 
 dow fescue and orchard grass are used in some reg- 
 ions where timothy does not thrive well. In many 
 localities a mixture of red or alsike clover with 
 timothy is used. Sudan grass, a very tall productive 
 variety, is coming into use in a number of states. 
 
 All of the grasses we have discussed are peren- 
 nials. Some farmers raise millets, which are annual 
 grasses, and use them for hay or pasture. Perennial 
 plants are those which grow year after year. An- 
 nuals grow for just one year. 
 
 You found that all the grasses have certain char- 
 acteristics in common: 1. Long, narrow, parallel- 
 veined leaves. 2. Numerous small fibrous roots. 
 3. Jointed stems. You found two kinds of flowering 
 heads represented by timothy and blue-grass. The 
 timothy head is a spike; blue-grass, a panicle. All 
 of our small grains, as well as corn, sorghum and 
 kaffir corn, belong to the Grass family. 
 
 Legumes. The clovers, alfalfa, cow-peas and soy- 
 beans belong to the Legumenosae family, but they are 
 commonly called legumes. They get the name from 
 the flat pod in which the seeds are borne, which is 
 characteristic of most of the family. Such a pod is 
 
58 STUDIES IN SCIENCE 
 
 called a legume. Our garden beans and peas are 
 good types of legumes. You probably discovered 
 the similarity between the flowers of clovers and 
 those of peas and beans. 
 
 Legumes are excellent forage plants containing 
 more nutritious foods than grasses. This is espe- 
 cially true of alfalfa and red. clover. Alfalfa is raised 
 more in the western states; clover in the states east 
 of the Missouri river. However, the acreage of alfalfa 
 is increasing year by year. Sweet clover is begin- 
 ning to find a place as a forage crop. Many farmers 
 in the Middle West are growing it instead of alfalfa. 
 
 Eed clover produces two crops each year. The 
 first is harvested for hay; the second usually for 
 seed. In the West alfalfa is cut from six to ten times 
 in one season. In the Mississippi Valley and adja- 
 cent states it is possible most seasons to secure three 
 cuttings. Sweet clover also yields three cuttings. 
 It must be harvested when young before the stems 
 become woody. 
 
 Soy-beans and cow-peas are frequently used as 
 soiling crops, but in the South they are harvested 
 for hay. They are annuals. Alfalfa and red and 
 white clover are perennials ; sweet clover is a biennial. 
 
 In addition to their value as food for animals, 
 legumes are important plants to aid in maintaining 
 soil fertility. They do this in three ways: 
 
FARM CROPS 59 
 
 1. They furnish a large amount of decaying roots, 
 stems, and leaves that enrich the soil. 
 
 2. Their long thick roots which penetrate the soil 
 so deeply aid in making it porous and in giving both 
 air and water a better opportunity to reach the roots. 
 
 3. They supply the soil with nitrogen, an element 
 that all seed plants must have in order to live and 
 grow. 
 
 You found nodules on the roots of clovers and other 
 legumes. These are growths caused by small living 
 organisms called bacteria. (One is a bacterium.) 
 The bacteria, which are either on the seed or in the 
 soil, attach themselves to the young clover roots. 
 The tissues of the roots grow around them forming 
 the small nodules. In these the bacteria live and mul- 
 tiply very rapidly. They take free nitrogen from the 
 air in the soil spaces and change it into a form that 
 clover can use, for, although there is plenty of free 
 nitrogen in the air surrounding clover and other 
 plants, they cannot use it in that form. 
 
 All the legumes have the bacteria nodules on their 
 roots. They are not only supplied with all the nitro- 
 gen they need, but their leaves, stems and roots are 
 all well stocked with it. If the plants are plowed 
 under, the nitrogen, which is now in the form of a 
 compound called a nitrate, goes into the soil and fur- 
 nishes a supply for other crops that are grown here. 
 
60 STUDIES IN SCIENCE 
 
 Nitrogen is frequently lacking in soils that are con- 
 stantly used for crops, so you can realize how impor- 
 tant it is to grow legumes in order to keep a suffi- 
 cient supply of nitrogen in the soil. 
 
 4. COTTON 
 
 Material. An entire cotton plant, some ripe bolls, 
 pictures of cotton gins and cotton factories, collec- 
 tion of cotton products. 
 
 The cotton plant. Study a cotton plant either in 
 the field where it is growing or have one in the school 
 room. How high does the plant grow! Examine. the 
 root and describe it. How deep in the ground does 
 it extend! Describe the stem. How close to the 
 ground does it begin to branch! Count the number 
 of large branches. Break or cut a stem at the largest 
 part. What parts can you find in the cross-section! 
 How does the structure differ from that of the corn 
 stem! 
 
 Describe a leaf. Compare leaves found on differ- 
 ent parts of the plant. "What is the greatest number 
 of lobes that you find in one leaf! The fewest! 
 What is the most common number! Which have 
 the greatest number, those on the upper or lower 
 branches! How are the leaves arranged with ref- 
 erence to each other, opposite or alternate! Look 
 on the under side of a leaf for a little hollow spot 
 
FARM CROPS 61 
 
 near the base of the midrib. What is in this depres- 
 sion or pit! How many such pits can you find on 
 one leaf! Taste the liquid. 
 
 The flower. Examine a flower. What do you find 
 at the lower part! How many fringed bracts are 
 there! Describe them. Pull them back till you can 
 see the cuplike calyx with five or six notches at the 
 top. What color is it! How many petals are there! 
 What different colors do you find! Look at flowers 
 of different ages to see if you can account for the 
 different colors. What insects have you seen around 
 the flowers! What do you find in the center of the 
 flower! You find a great number of stamens all 
 grown together to form a large tube. Remove the 
 stamen tube. In an old flower it will come off easily 
 leaving the pistil which is in the center of the flower. 
 Find the large green ovary at the base of the pistil. 
 Note the slender style and the stigma at the top. 
 How many division lines has the ovary! Find flow- 
 ers that are withering, and those from which the 
 withered parts have dropped. Determine what part 
 of the flower develops into the fruit or boll. What 
 other parts of the flower remain attached to the boll! 
 
 The seeds. Cut open lengthwise an ovary from 
 which the dried corolla and stamens have just fallen. 
 Note position of the rudimentary seeds. Cut open 
 another that is about an inch long and note the white 
 
62 STUDIES IN SCIENCE 
 
 silvery substance growing around the seeds. Cut 
 open one that is still larger to find that the white 
 substance is forming into threadlike fibers. Study 
 a ripe boll. Where does it open! How many sections 
 has it! Remove the fibers from the seeds. Where are 
 they attached! How many seeds in one section! 
 In one boll! Count a number to find variations. 
 Straighten out the fibers on one seed. How long are 
 they! Twist some of them together and note their 
 strength. 
 
 Remove the cotton films from around the seeds 
 and examine the seeds. Take off the hull and study 
 the kernel. Crush some of the kernels on a piece of 
 paper. What do you find? 
 
 Discussion, From an economic standpoint cotton 
 is one of the most important crops that we have in 
 the United States. You found that the plant grows 
 from three to six feet in height. It has a large tap- 
 root that sends out a number of branches. These 
 grow to quite a depth and anchor the plant firmly in 
 the soil. The stem resembles that of a shrub or tree 
 with a brownish bark. Inside the bark is a strong 
 layer of wood and in the middle is the pith. The 
 stem is unusually strong and woody for an annual. 
 In fact, in warm climates it is a perennial living on 
 from year to year just as our shrubs do. 
 
 The leaves are arranged alternately and the upper 
 
FARM CROPS 63 
 
 leaves have more lobes than the lower ones. One 
 of the most interesting things about the leaves is 
 that they secrete nectar. On the under 'side of the 
 midrib not far from the base is an oval shaped 
 depression or pit. In this the sweet nectar collects. 
 Sometimes a large drop stands up like a bit of 
 honey. On some leaves a number of the veins have 
 these pits, while on others you may not find any. 
 
 The flower has at the lower part three fringed 
 bracts that enclose the bud and later the fruit. When 
 the flower first opens the petals are a creamy white. 
 A little later they become a pale pink. The next 
 day they have changed to a reddish purple. They 
 then begin to wither slightly and usually fall by the 
 close of the second day. The plant begins to blossom 
 early in the summer and continues blossoming all 
 summer and early fall, so you may find on the plant 
 at the same time flowers and fruit in all stages of 
 development. 
 
 The ovary develops into the fruit or boll. The 
 fringed bracts still remain on the bolls. Cotton grow- 
 ers call these the "squares." There are usually five 
 sections in the boll, which split open at the top. The 
 fibers are fastened to the blunt upper end of each 
 seed. They are long, strong fibers. These charac- 
 teristics make them very valuable for spinning and 
 weaving. After the fibers are removed the seed 
 
64 STUDIES IN SCIENCE 
 
 remains covered with a soft coat called linters. The 
 outside covering of the seed is rather hard. The 
 kernel is white and contains considerable oil. 
 
 History. Cotton has been in use since the begin- 
 ning of written history, and no one knows how long 
 before. Its earliest known home is India,. From here 
 it was introduced into Egypt and other warm coun- 
 tries of the eastern continent. 
 
 Columbus found cotton in the New World in the 
 West Indies. It was also found in Mexico and South 
 America by some of the early explorers. 
 
 Cotton was introduced into the southern states 
 early in the history of the colonies. Two distinct 
 species are raised here, the sea-island and the upland 
 cotton. The former is raised along the coast of South 
 Carolina, Georgia, Florida and in the West Indies. 
 The upland cotton is grown in most of the other 
 cotton growing states. Cotton may be raised with 
 profit as far north as 30. Look on a map to find 
 what states are included in the cotton region. 
 
 Uses, The fibers are removed from the seeds by 
 a machine called a cotton gin. The seeds rest against 
 the teeth of a number of revolving saws which pull 
 the fibers from the seeds. You know from your study 
 of history how very important the invention of the 
 cotton gin was. After the cotton is ginned it is 
 pressed into large bales and shipped to the cotton 
 
FARM CROPS 65 
 
 factories where the fibers are spun into threads and 
 woven into cloth. 
 
 The seeds are taken to another machine which 
 removes the linters. This product is used in the 
 making of mattresses, in upholstering furniture and 
 in making cotton felt cloth. 
 
 The hulls are removed from the seeds, crushed 
 and used for fertilizers or are fed to cattle. The 
 kernels are pressed in a great pressing machine in 
 order to obtain the oil that is in them. The oil is used 
 for cooking purposes and to serve with salads instead 
 of olive oil. It is used in the industries especially 
 in mixing paint and making soap. 
 
 The pressed remains of the kernels is known as 
 oil-cake. It is used to feed cattle and is usually sold 
 in the form of cotton-seed meal. 
 
 In some places where fuel is scarce the larger parts 
 of the cotton stems are used for heating purposes. 
 
 Culture. Cotton is planted in rows from three to 
 four feet apart. It is cultivated in much the same 
 way that corn is. Weeds should be kept down and 
 a soil mulch produced to conserve the moisture. Cot- 
 ton growers are giving much attention recently to 
 the selection of good seeds. Plants that produce bolls 
 early and produce them in large numbers are marked 
 and the seeds from these plants saved for the next 
 crop. By this simple selection method the crop in 
 
66 STUDIES IN SCIENCE 
 
 some regions has been increased from 15 to 25 per 
 cent in a period of three years. 
 
 Cotton projects. If you live in a region where 
 cotton is raised, you should plant a small plot of your 
 own. Try saving the seeds from the plants that pro- 
 duce well and see to what extent you can increase 
 your yield. 
 
 Make a collection of all the different products 
 derived from cotton. Mount these on a chart. 
 
 Make a list of all the uses of cotton that you know. 
 How valuable is the cotton crop in your community? 
 In the United States? 
 
CHAPTER III 
 
 WEEDS 
 
 Material. A collection of weed-plants, leaves, fruit, 
 and seeds. Stiff paper for charts or booklets. 
 
 Study. For study you may group weeds with 
 reference to the location in which you find them 
 growing; as garden, lawn, pasture and meadow, road- 
 side, vacant lot and field. 
 
 Go into your garden, yard or field and count the 
 number of different kinds of weeds that are grow- 
 ing there. Write the names of those that you know. 
 How close together do the plants stand! To what 
 extent are different species growing together? 
 
 Make a special study of each kind. Use the fol- 
 lowing outline to keep a record of your work: 
 
 1. Name: 
 
 2. Location: garden, lawn, pasture, roadside, 'cultivated field, 
 meadow, etc. 
 
 3. Annual, biennial, perennial. 
 
 4. Habit of growth: erect, procumbent, creeping, climbing, etc. 
 
 5. Characteristics of underground parts: a. roots, thick, fleshy, 
 long, fibrous, b. underground stem, rootstock, long branching, etc. 
 
 6. Leaves: simple, compound, smooth, hairy, large, small. 
 
 7. Flowers: kind, simple or composite; dates of flowering, spe- 
 cial characteristics. 
 
 67 
 
68 STUDIES IN SCIENCE 
 
 8. Fruit: date of maturing; seeds, large, small, number, special 
 adaptations for distribution. 
 
 9. Methods of control. 
 
 10. Native home and interesting facts. 
 
 Pigweed, sometimes called careless weed, abundant 
 in many gardens and fields, is a good one with which 
 to begin. It is an annual; that is, it starts from the 
 seed each year, produces seed and then dies. It has 
 a thick taproot with many branches. The leaves are 
 simple, large on the lower branches and small on the 
 upper ones. The flowers are very inconspicuous, 
 growing in dense, greenish clusters. 
 
 The seeds are small and are produced in great num- 
 bers. You can easily estimate the number of seeds 
 on one plant by counting the exact number on a small 
 branch, then count the number of branches of the 
 same size and calculate the entire number of seeds. 
 The easiest way to get the seeds is to rub them out 
 of the chaff onto a sheet of paper. If you have 
 patience you can remove all the seeds from a large 
 plant and put them into a jar or bottle. This gives 
 a very accurate idea of the great number of seeds 
 that one plant produces, and explains why the weed 
 is so abundant. 
 
 Compare with pigweed other annuals as smart- 
 weed, foxtail grass, and rag weed, noting character- 
 istics that are common, and those that are dissimilar. 
 Find some plants whose stems were cut off a few 
 
WEEDS 69 
 
 inches above the ground earlier in the season, and 
 describe what has taken place. 
 
 Find in vacant lots, pastures or roadsides, some 
 types of biennial weeds; that is, weeds that grow 
 from seed the first year, blossom the second year, bear 
 fruit and die. 
 
 Some of the most familiar biennials are burdock, 
 field or bull thistles, wild parsnip and wild carrot. 
 Find plants of the first year's growth and those of 
 the second. Compare them noting differences. 
 
 In lawns, pastures and in some cultivated fields 
 you will find weeds whose underground parts con- 
 tinue to live year after year. .Each year they send 
 up new stems and leaves, blossom and bear seeds. 
 These are perennials. Dandelion, plantain, curly 
 dock, creeping mallow or cheese weed are common 
 perennials. Make careful observation of their under- 
 ground parts to determine how they live through the 
 winter. Note also any special adaptations they may 
 have to spread by means of roots or underground 
 stems. Summarize the great number of character- 
 istics that such a perennial as the dandelion has that 
 make it a successful lawn plant. 
 
 Compare weeds of the same species growing in 
 different locations, as a dandelion on the lawn with 
 one growing in tall grass. How do you account for 
 the difference! 
 
70 STUDIES IN SCIENCE 
 
 Begin at once making a collection of the weeds 
 of your neighborhood. Press a leaf of each species 
 and when possible a flower. Preserve also fruiting 
 heads or pods and seeds. Mount your specimens on 
 cardboard making a weed chart or booklet. 
 
 The easiest way to press the plants is to spread 
 them out on a piece of newspaper, taking care to 
 smooth out the leaves, then place several layers of 
 the paper on top. Lay them down flat and put a 
 weight upon them. After an interval of several days 
 all moisture will have been absorbed and the plants 
 will be ready for mounting. There are two ways to 
 mount them. You may use small strips of paper, 
 with mucilage on one side, to form loops over the 
 stems ; or you may sew the specimen fast to the sheet. 
 
 Discussion. Most garden weeds and those found 
 in cultivated fields are annuals. You found that 
 pigweed, foxtail, smartweed and crab-grass each pro- 
 duces a large number of seeds. This is character- 
 istic of most annuals and is of great importance since 
 these plants are wholly dependent upon seeds for 
 reproduction. 
 
 An interesting fact about the seeds is that they 
 do not all germinate and grow at the same time. No 
 doubt you have weeded your garden during the 
 growing season and then have gone back within a 
 week to find another crop of weeds of the same kind. 
 
WEEDS 71 
 
 If you continue this all summer, the weeds will still 
 continue to grow to a certain extent. The seeds of 
 some weeds probably remain a number of years in 
 the soil before they finally germinate and grow. 
 Agriculturists have found by experiment that only 
 one of the two seeds of the cocklebur grows the first 
 season. The other one may grow the second year 
 or may wait several years. 
 
 Another characteristic that is an advantage to 
 annuals is that they may start to grow in the middle 
 of the summer after cultivation has ceased and yet 
 succeed in maturing their seeds before cold weather. 
 Some of them, like the pigweed, cocklebur, foxtail 
 and others, when cut off, send out new branches from 
 the injured stems, blossom and bear seeds in spite 
 of the injury. 
 
 The dandelion has many characteristics that make 
 it a successful plant. It is so hardy that it can blos- 
 som and produce seeds when the temperature is 
 quite low. In some places where it is sheltered even 
 in the North Central States it produces seeds all 
 winter. Its large root provides food for rapid growth 
 in the spring. You probably found in the heart of 
 the rosette tiny buds that are ready to open, up just 
 as soon as conditions are favorable. The growing 
 center of the rosette is below the surface of the soil 
 so that a lawn mower does not injure it in the least. 
 
72 STUDIES IN SCIENCE 
 
 In fact, the mower is a friend of the dandelion, since 
 it cuts away the grass allowing plenty of light to 
 reach the weed. The milky secretion, which is bitter, 
 is not liked by most animals, so the plant is not cropped 
 when it grows in pastures. In addition to all these 
 characteristics for successful growth, it has a great 
 number of seeds that may be carried long distances 
 by the wind. 
 
 The dandelion leaves are used for greens and salads 
 and the root for medicine, so, while we often regard 
 it as an undesirable weed in the lawn, it also has use- 
 ful qualities. In some places near large cities it is 
 grown in gardens to supply the market with greens. 
 
 The thistle, burdock, and other biennials grow 
 from seeds and produce large fleshy roots and a num- 
 ber of leaves the first year. The second year they 
 send up a flowering stem and use the great supply of 
 food they have stored in the roots to produce seeds. 
 
 Annuals are usually found in gardens and culti- 
 vated fields. Since they start from seeds each year 
 the open plowed ground gives them a chance to get 
 a foothold. They have little opportunity to start in 
 lawns, meadows and pastures because the space is 
 already .occupied, and there is no good place for the 
 seeds to settle down and germinate. 
 
 Perennials are most abundant in pastures, old mead- 
 ows and roadsides; but even perennials have a hard 
 
WEEDS 73 
 
 time to gain a foothold in grassy areas. Some of them 
 get fairly well started but are crowded out by the 
 grasses. The only perennials that succeed in hold- 
 ing their places are those that have special adapta- 
 tions like the dandelion, the Canada thistle, milk- 
 weed, curlydock and different kinds of daisies. Per- 
 ennials when once established are the hardest of 
 all weeds to combat, because they not only produce 
 seeds for new plants but the old plants continue 
 to live. Many of them also spread by their under- 
 ground stems. 
 
 There are a few perennials that thrive well in 
 cultivated soils. Among them are the wild morn- 
 ing-glories, one with a large white flower, the other 
 with a pink flower sometimes called wild sweet 
 potato. Quack grass is perhaps even worse than 
 the wild morning-glories. All of these spread by 
 underground stems called rootstocks. A small piece 
 of stem under right conditions starts a new plant, 
 so that cultivation often tends to scatter these weeds 
 instead of destroying them. 
 
 Many weeds of all three classes possess special 
 devices for distributing their seeds that aid them 
 in getting possession of new fields. You have 
 observed the feathery pappus fliers of the thistles, 
 wild lettuce, and dandelion, the burs of cocklebur 
 and burdock, the tumble weeds that roll along scat- 
 
74 STUDIES IN SCIENCE 
 
 tering their seeds as they go, as Eussian thistle, and 
 old witch grass. Some smooth seeds of such plants 
 as the ragweed, velvetweed, and pigweed are car- 
 ried long distances, and are blown over the snow 
 and ice in the winter time. Water helps to dis- 
 tribute seeds by washing them down slopes, by carry- 
 ing them in streams and scattering them over the 
 land during the high waters in the spring. 
 
 Why weeds are not desirable. Make a list of all 
 the reasons you can think of why you do not wish 
 weeds to grow in your fields and garden. 
 
 1. They use up moisture and mineral foods that 
 you would like to have left for your cultivated crops. 
 
 2. As a rule, they are rapid growers and can 
 easily shade the smaller cultivated plants. 
 
 3. Many of them can thrive in crowded condi- 
 tions better than some of our cultivated crops. 
 
 4. In grain fields they increase the cost of har- 
 vesting by occupying a large space in the sheaves. 
 
 5. In threshing, some of the seeds are certain to 
 become mixed with the grain, thus making it inferior 
 either for market or seeding purposes. The same 
 thing may be said of weeds in meadows. Hay with 
 a large per cent of weeds is not as valuable as pure 
 hay. 
 
 6. Some weeds are detrimental because they are 
 poisonous to stock. 
 
WEEDS 75 
 
 7. Some provide a shelter for injurious insects 
 during the winter. 
 
 8. Many weeds are such coarse, unsightly plants 
 that we do not like to see them around a home or 
 farm. 
 
 Getting rid of weeds. How to get rid of weeds 
 is a problem that all gardeners and farmers must face. 
 The more you know about the lives and habits of 
 these plants, the better able you will be to exter- 
 minate them. Annuals have but one way to repro- 
 duce themselves; if you can prevent their producing 
 seeds, it will not take many years to eradicate them 
 altogether. Rotation of crops aids greatly in con- 
 trolling these weeds. 
 
 Biennials may be controlled in much the same 
 way as annuals. If they are dug out the first year 
 or cut down and burned the second year before the 
 seeds mature, they are easily destroyed. It does 
 little good to cut off their tops before they send 
 up their flowering stems, for they will continue to 
 grow and send up new stems until they have a 
 chance to produce flowers and seeds. 
 
 Perennials are harder to handle since they are 
 not dependent upon seeds for reproduction, but con- 
 tinue to live and spread year after year. Sometimes 
 a change of crop will help to eradicate them. Pas- 
 tures and meadows that are badly infested with 
 
76 STUDIES IN SCIENCE 
 
 perennials and biennials should be plowed up and 
 planted to grains. Perennials in small plots may 
 be dug up root and all and burned. A method 
 sometimes used is to cover a small plot with a 
 thick coating of straw or manure. Sometimes tar 
 paper is used instead. This covering prevents the 
 leaves from manufacturing food since they are 
 entirely shut off from the sunlight. The roots can- 
 not live long without food so the plants are really 
 starved to death. This method is too expensive 
 to use except in small tracts. Another method that 
 is successful although very expensive is known as 
 fallowing. Instead of trying to raise a crop of any 
 kind the farmer plows under the first crop of weeds 
 in the spring, then discs the soil every few days 
 during the growing season so that no leaves have 
 an opportunity to get above the ground and manu- 
 facture food. 
 
 You will be interested to know that most of our 
 worst weeds are not natives of America. They have 
 been introduced from other countries, usually with 
 the seeds of cultivated crops. Some were brought 
 over by the early colonists. Others have come in 
 rather recently. Most of them possess character- 
 istics that enable them not only to gain a foothold 
 in our soil but to keep possession even in the face 
 of hard conditions. 
 
WEEDS 77 
 
 LIST OF COMMON WEEDS 
 EXPLANATION OF TEEMS AND SYMBOLS 
 
 The letters (A), (B), (P), following the name indicate whether 
 the weed is an annual, a biennial, or perennial. 
 
 The scientific name is found in parentheses after the common 
 name of each weed. 
 
 Fam. stands for the name of the botanical family to which the 
 plant belongs. 
 
 Hab. stands for habitat and tells the place in which the weed is 
 found growing most abundantly. 
 
 N. H. gives the native home of the weed or the country from which 
 it has been introduced. 
 
 Char. Under this term the characteristics that make the weed 
 hard to combat are given. 
 
 Control. Some of the best methods of combatting each weed are 
 suggested. 
 
 Butter 'print, velvet leaf: (A) ; (Abutilon, abutilon) ; Family, 
 Mallow; Hab., Cultivated fields, gardens; N. H., Asia; Char., Many 
 seeds scattered by the wind shaking the tall stem. Leaves covered 
 with soft hairs which enable the plant to stand drought. Control, 
 Pulling or hoeing before plants blossom. Cutting mature plants, 
 piling and burning. 
 
 Burdock: (B) ; (Actium, minus); Fam., Thistle; Hab., Vacant 
 lots, waste places, fence corners; N. H., Europe; Char., Deep thick 
 roots, lower leaves very large. Fruit a bur. Seeds scattered by 
 animals; Control, Deep cutting below crown before flowers appear. 
 Cutting, piling, and burning mature plants. 
 
 BuckJiorn: (P) ; (Plantago lanceolata) ; Fam., Plantain; Hab., 
 Fields, meadows, pastures; N. H., Europe and Asia; Char., Thick 
 rootstock which lives over winter. Flowers and bears seeds from 
 April to October. Seeds scattered in clover, alfalfa, and other hays; 
 Control, Plowing under meadows or pastures and cultivating thor- 
 oughly. Where plants are few, cutting out. 
 
 Wild carrot, Queen Anne's lace: (B) ; (Daucus carota) ; Fam.. 
 Parsley; Hab., Roadsides, lawns and meadows; N. H., Europe and 
 Asia; Char., Long root, numerous seeds distributed by wind, birds 
 and water; Control, Cutting roots well below crown. Repeated cut- 
 ting during summer. 
 
78 STUDIES IN SCIENCE 
 
 Canada thistle: (P) ; (Carduus Arvensis) ; Fam., Thistle; Hab., 
 Pastures, waste places; N. H., Europe; Char., Spreads by a run- 
 ning rootstock from 2 to 3 ft. deep. Seeds scattered by wind. .Con- 
 trol, Covering with tar paper or other material for an entire season or 
 two to starve out the rootstocks. Repeated cutting during the grow- 
 ing season for at least two years. 
 
 Chickiueed: (A); (Alsine media); Fam., Pink; Hab., Moist 
 places, edges of gardens, meadows, lawns; N. H., Europe and Asia; 
 Char., Blossoms all spring and summer. Many seeds; Control, 
 Rotation of crops. Crowding out by winter crops as rye, or crimson 
 clover. 
 
 Cocklebur: (A); (Xanthium glabratum) ; Fam., Ragweed; Hab., 
 Cultivated fields, especially in moist ground, in cornfields; N. H., 
 Europe; Char., Hardy, rapid grower. Sends out new branches when 
 stem is cut off. Bur widely scattered by animals; Control, Pulling 
 before burs are formed. Burning mature plants. 
 
 Corn-cockle: (A); (Agrostemma Githago) ; Fam., Pink; Hab., 
 Grain fields, especially wheat and rye; N. H., Europe and Asia; 
 Char., Many small seeds. Blossoms all summer; Control, Hand 
 pulling, screen grain, seeds, crop rotation. 
 
 Crab-grass, finger-grass: (A); (Syntherisima Sanguinalis) ; 
 Fam., Grass; Hab., Gardens and cultivated fields; N. H., Europe; 
 Char., Many small seeds. Takes root at joints; Control, Hand pull 
 ing, burn plants, burn stubblefields. 
 
 Creeping Mallow, Cheeseiveed: (P) ; (Malva rotundifolia) ; 
 Fam., Mallow; Hab., Dooryards, waste places, gardens; N. H., Eu- 
 rope and Western Asia; Char., Very long root. Stands drought; 
 Control, Thorough cultivation, digging out by root. 
 
 Curled dock, yellow: (P) ; (Rumex Crispus) ; Fam., Buckwheat; 
 Hab., Waste places, old pastures; N. H., Europe and Asia; Char., 
 Long, thick root. Many seeds. Control, Cutting root several inches 
 below surface before seeds ripen. 
 
 Dandelion: (P) ; (Taraxacum taraxacum); Fam., Chicory; 
 Hab., Lawns, pastures, roadsides; N. H., Europe, Asia, and probably 
 North America; Char., Long, thick root. Many seeds, widely dis- 
 tributed by wind. Blossoms all year. Control, cutting root far 
 below surface before plant goes to seed. 
 
 Field bindweed, small bindweed: (P) ; (Convolulus arvensis) ; 
 Fam., Morning Glory; Hab., Cultivated fields; N. H., Europe and 
 Asia; Char., Spreading by rootstocks which form buds and start 
 
WEEDS 79 
 
 ne\v plants; Control, Cutting tip frequently during the entire 
 summer. Smothering with paper or straw. 
 
 Field sorrel, horse sorrel: (P) ; (Rumex acetosa) ; Fam., Buck 
 wheat; Hab., Pastures, meadows, cultivated fields; N. H., Europe; 
 Char., Spreading by running rootstocks. Numerous seeds. Con- 
 trol, Crowding out with clover and grasses. Lime on soil to enable 
 clover to grow well. 
 
 Foxtail, yellow: (A); Pigeon grass; (Ixophorus glaucus) ; 
 Fam., Grass; Hab., Garden, cultivated fields; N. H., Europe; Char., 
 Many seeds retaining vitality for years. Send out new stems when 
 cut off. Strong fibrous roots. Control, Mowing and burning stub- 
 blefields. In garden pulling out by roots when soil is soft after a 
 rain. 
 
 Foxtail, green: (A); (Ixophorus viridis) ; Fam., Grass; Hab., 
 Gardens, cultivated fields; N. H., Europe; Char., Same as above. 
 Control, Same as yellow foxtail. 
 
 Horse nettle: (P) ; (Solanum Carolinense) ; Fam., Potato; 
 Hab., Cultivated fields, pastures; N. H., United States and Canada; 
 Char., Numerous seeds. Spreads also by a strong rootstock. Ex- 
 ceedingly hardy; Control, Cutting off close to ground and salting. 
 
 Horsctveed, colt's tail: (A); (Laptilon Canadense) ; Fam., This- 
 tle; Hab., Pastures, roadsides, waste places, gardens; N. H., North 
 America and South America; Char., Many seeds with pappus dis- 
 tributed by wind; Control, Cutting and burning. Pulling before 
 seeds ripen. 
 
 Jimson-iveed: (A); (Datura Stromonium) ; Fam., Potato; Hab., 
 Waste places, barnyards; N. H., Tropical Asia; Char., Many seeds, 
 Hardy; Control, Pulling when young. Cultivation. 
 
 Knotgrass, doorwecd: (A); (Polygonum aviculare) ; Fain., 
 Buckwheat; Hab., Yards, roadsides, along walks; N. H., North 
 America, Europe, and Asia; % Char., Spreading close to ground, not 
 easily injured by trampling; Control, Pulling or cutting before seeds 
 ripen. 
 
 Lamb's quarters, goosefoot: (A); (Chenopodium Album); 
 Fam., Goosefoot; Hab., Gardens, cultivated fields; N. H., Europe 
 and Asia; Char., Many seeds, produces new stems when cut off; 
 Control, Pulling or hoeing before seeds ripen. Thorough cultivation. 
 
 Lamb's quarters, city goosefoot: (A); (Chenepodium urbicum) ; 
 Fam., Goosefoot; Hab., Gardens, along walks, waste places; N. H., 
 Europe; Char., Same as last and control the same. 
 
80 STUDIES IN SCIENCE 
 
 Lettuce, wild, prickly lettuce: (A); (Lactuca Scariola) ; Fain., 
 Chicory; Hab., Waste places, gardens, old fields; N. H., Europe; 
 Char., Many seeds with pappus, scattered by the wind. Prickles 
 protect it from animals. Plants that start late in summer live over 
 winter; Control, Early cultivation or hoeing in spring to kill winter 
 plants. Cutting and burning before seeding. 
 
 Morning-glory, wild, hedge bindweed: (P) ; (Convolvulus sep- 
 ium); Fam., Morning-glory; Hab., Cultivated fields, fence rows; 
 N. H., North America, Europe and Asia; Char., Spreads by seeds 
 and running rootstocks; Control, Cultivating every ten days or two 
 weeks all summer, in small plots, smothering by tar paper. 
 
 Milkweed: (P) ; (Asclepias syriaca) ; Fam., Milkweed; Hab., 
 Cultivated fields, meadows, pastures; N. H., All parts of United 
 States; Char., Seeds with pappus widely scattered by wind. Spreads 
 also by deep running rootstock; Control; Repeated cutting during 
 the entire summer, continued for two years. 
 
 Mullein: (B) ; (Verbascum thapsus) ; Fam., Figwort; Hab., 
 Pastures, roadsides; N. H., Europe; Char., Many small seeds which 
 retain vitality for years. Rosette of thick leaves close to ground, 
 well protected; Control, Cutting off rosette below crown in fall or 
 early spring. 
 
 Mustard, wild, cJiarlock: (A); (Brassica arvensis) ; Fam., Mus- 
 tard; Hab., Grain fields, especially oats, meadows; N. H., Europe; 
 Char., Many seeds which mix with grain when threshed; Control, 
 Burning stubble or harrowing to start seeds. Plowing under in 
 fall. Pasture with sheep. 
 
 Old witch grass, tickle grass: (A); (Panicum capillare) ; Fam., 
 Grass; Hab., Gardens, cultivated fields, stubblefield; N. H., South- 
 ern Canada and all of United States; Char., Many seeds, rapid 
 grower. Plant breaks off in the fall near the ground; Control, 
 mowing and burning. 
 
 Parsnip, wild: (B) ; (Pastinaca s'ativa) ; Fam., Parsley; Hab., 
 Waste places, roadsides; Char., Strong root, hardy plant, many 
 seeds; Control, Cutting out below crown first-year plants. Mowing 
 and burning second year. 
 
 Plantain: (P) ; (Plantago major); Fam., Plantain; Hab., Lawns, 
 roadsides, pastures; N. H., Europe; Char., Many seeds, rosette of 
 leaves close to ground, stands trampling; Control, In yard, cutting 
 below surface. In pastures, crowding out w r ith clover. 
 
 Pepper grass, tongue-grass: (A); (Lepidium Virginicum) ; Fam., 
 
WEEDS 81 
 
 Mustard; Ilab., Dooryards, waste places, gardens, meadows; N. H., 
 Canada and United States; Char., Many seeds, plants start in the 
 fall and live over winter; Control, Pull up by roots in lawns. Thor- 
 ough cultivation in fields. 
 
 Pigiveed, careless weed: (A) ; (Amaranthus retroflexus) ; Fam., 
 Goosefoot; Hab., Gardens, cultivated fields; N. H., Tropical America; 
 Char., Numerous small seeds. Send out new stems that produce seed 
 when cut off near the ground. Very hardy; Control, Pulling before 
 seeds ripen. Burning in fall all the plants that have gone to seed. 
 
 Pigweed, red-stemmed: (A) ; (Amaranthus hybridus) ; Fam., 
 Goosefoot; Hab., Garden, fields; N. H., Tropical America; Char., 
 Same as above. Control, Same. 
 
 Purslane, pussley: (A) ; (Portulaca oleraceus) ; Fam., Pur- 
 slane; Hab., Gardens, cultivated fields; N. H., Southern United 
 States, and Tropical America; Char., Blossoms and bears seed all 
 summer. Seeds many, plant very juicy. Can stand drought; Con- 
 trol, Pulling out when young, drying and burning, or feeding to hogs. 
 
 Pungent meadow-grass: (A); (Eragrostis major) ; Fam., Grass; 
 Hab., Gardens, waste places; N. H., Europe; Char., Many seeds, 
 strong roots; Control, Hoe or plow out before seeding. 
 
 Quack-grass, couch-grass: (P) ; (Agropyron repens) ; Fam., 
 Grass; Hab., Grain fields, lawns, gardens; N. H., Europe; Char., 
 Strong rootstock that spreads rapidly. Clings so firmly in soil that 
 it cannot be pulled up; Control, Plow in fall, harrow or rake, pile 
 and burn plants. Two plowings may be necessary. 
 
 Ragweed, common: (Ambrosia artemisiaefolia) ; Fam., Rag- 
 weed; Hab., Stubblefield, cornfield, pastures, gardens; N. H., North 
 America, South America; Char., Many seeds. Can grow and ma- 
 ture seeds late in summer. Can stand dry weather; Control, Work- 
 ing and burning stubble. Early fall plowing. 
 
 Ragweed, horseivood: (A); (Ambrosia trifida) ; Fam., Ragweed; 
 Hab., Roadsides, along streams, fence corners; N. H., United States 
 and Canada; Char., Many seeds carried by birds, not a very bad 
 weed; Control, Pulling before seeding. Burning stubble. Pasturing 
 with sheep. 
 
 Shepherd's purse: (A); (Bursa bursa pastor is ); Fam., Mus- 
 tard; Hab., Waste places, gardens, lawns; N. H., Europe; Char., 
 Plants that start late in the summer live over winter and produce 
 seeds early. Flowers all summer; Control, Hand pulling from lawns. 
 Fall plowing in gardens and fields. 
 
82 STUDIES IN SCIENCE 
 
 Sow-thistle: (A); (Sonchus oleraceus) ; Fam., Chicory; Hab., 
 Waste places, roadsides, fence corners; N. H., Europe, Asia; Char., 
 Many seeds with pappus, distributed by the wind; Control, Cutting 
 while young, burning mature plants. 
 
 Spanish needle, "bur marigold: (A) ; (Bidens connata) ; Fam., 
 Thistle; Hab., Low regions in fields and pastures; N. H., United 
 States and Canada; Char., Seeds with bristles that stick to animals 
 and clothing; Control, Thorough cultivation, cutting before seeds 
 ripen. 
 
 Smartwecd, spotted smartweed: (A) ; (Polygonium persicaria) ; 
 Fam., Buckwheat; Hab., Gardens, cultivated fields, especially low 
 regions; N. H., Europe; Char., Seeds many, distributed in grain; 
 Control, Cutting before seeds ripen, burning stubble, pulling or 
 hoeing in gardens. 
 
 Spurge, spotted: (A); (Euphorbia maculata) ; Fam., Spurge; 
 Hab., Gardens, cultivated fields, roadsides; N. H., North America.; 
 Char., Many seeds. Grows prostrate forming a mat on the ground. 
 Control, Hoeing or pulling, through cultivation. 
 
 Spurge, upright, spotted spurge: (A); (Euphorbia nutens) ; 
 Fam., Spurge; Hab., Gardens, cultivated fields, roadsides; N. H., 
 North America; Char., Many seeds. Same as above but stands erect 
 instead of spreading on ground; Control, Hoeing or pulling; 
 thorough cultivation. 
 
 Spreading orache: (A) ; (Atriplex patula) ; Fam., Goosefoot; 
 Hab., Roadsides, along walks, waste places; N. H., Europe and Asia; 
 Char., Many seeds, rapid grower, many branches; Control, Pulling 
 or hoeing before flowers appear. 
 
 Squirrel-grass, wild Parley: (P) ; (Hordeum jubatum) ; Fam., 
 Grass; Hab., Roadsides, fence corners, meadows; N. H., Canada and 
 Northern United States; Char., Long beards, seeds scattered by 
 wind and water; Control, Pulling, cutting or hoeing before seeds 
 ripen. 
 
 Tunibleweed: (A); (Amaranthus graecizans) ; Fam., Amaranth; 
 Hab., Grain fields, old fields, roadsides; N. H., Tropical America; 
 Char., Many branches forming a round head which breaks off close 
 to the ground, rolls over and over scattering the many small seeds; 
 Control, Burning the mature weeds in the fall. Pulling or hoeing 
 before seeding. 
 
 Thistle, pasture or lull thistle: (B) ; (Carduus lanceolatus) ; 
 Fam., Thistle; Hab., Pastures, roadsides; N. H., Europe and Asia; 
 
WEEDS . 83 
 
 Char., Deep root, many sharp spines, seeds scattered by wind; Con- 
 trol, Cutting off root well below the crown. 
 
 Vervain Hue, wild hysop: (P) ; (Verbena Castata) ; Fain., Ver- 
 vain; Hab., Pastures, meadows, waste places; N. H., Southern Can- 
 ada and United States; Char., Hardy, stands drought, not a very 
 bad weed; Control, Cultivation and mowing. 
 
 White top, daisy fleabane: (A) ; (Erigeron annuus) ; Fain., 
 Thistle; Hab., Meadows, pastures, oat fields; N. H., Europe; Hab., 
 Plants started in the fall live over winter and blossom early. Many 
 seeds; Control, If very abundant in meadows plow under and plant 
 corn. Pull out by roots. 
 
 Wild bucTtiolieat, fcZacfc "bindweed: (A); (Polygonum convolvu- 
 lus) ; Fam., Buckwheat; Hab., Cornfield, grain, fence rows, gardens; 
 N. H., Asia. Brought here from Europe; Char., Climb or twine 
 around corn and wheat. Many seeds; Control, Early fall plowing 
 and harrowing. Pulling or mowing and burning before seeds ripen. 
 
 Wild sweet potato: (P) (Ipomea pandurata) ; Fam., Morning- 
 glory; Hab., Cultivated fields, meadows; N. H., Canada and United 
 States; Char., Thick, fleshy roots that send up new plants. Many 
 seeds; Control, Deep cutting, salting, mowing and burning tops 
 several times during the season. 
 
 Yarrotv, milfoil: (P) ; (Achillea millefolium) ; Fam., Thistle; 
 Hab., Pastures, roadsides, lawns; N. H., United States, Europe, and 
 Asia; Char., Spreads by horizontal rootstocks, very hardy; Con- 
 trol, Pulling, cutting and burning. 
 
CHAPTER IV 
 
 TEEE STUDIES 
 
 Material. Trees of the neighborhood, leaves, twigs, 
 fruit and seeds for indoor study and for charts and 
 booklets. , 
 
 "-Spray 
 
 Large 
 
 Irinik or bole 
 
 Fig. 16. The parts of a tree. 
 
 Study. How many trees in your neighborhood do 
 you know? If you do not know most of them set 
 
 84 
 
TREE STUDIES 35 
 
 about learning them. Do not be satisfied simply 
 to distinguish an oak from a maple or a pine from 
 a fir, but learn the exact species of every tree in 
 your community. 
 
 Select a special tree for study. Stand a short dis- 
 tance from it and name all the parts you can see. 
 If you do not know the names, consult Fig. 16. 
 
 What is the shape of the crown? Is the top 
 rounded, flat or pointed? Is it dense or open? What 
 
 Fig. 17. Tree forms: spherical and broadly conical. 
 
 is the character of the branching? Does the trunk 
 break up into a number of branches or extend un- 
 broken to the top? Note the twigs and determine 
 whether they are thick and erect, slender and droop- 
 ing, few or many. Examine the bole; what is its 
 color? Compare with the branches and twigs. 
 Describe the bark. Is it smooth, furrowed or scaly? 
 Are the furrows or fissures deep or shallow? Do 
 they extend up and down or around the trunk? 
 
86 
 
 STUDIES IN SCIENCE 
 
 How do the ridges compare with the furrows as to 
 width? Look at two or three different species of 
 trees until you are certain that each has its own 
 bark pattern. Look also for differences in shape 
 and branching. Stand at some distance from the 
 trees and make an outline sketch of the different 
 type forms. Consult Figs. 17 and 18. Compare the 
 forms of trees standing close together with those of 
 the same species standing alone. To what extent are 
 
 Fig. 18. Tree forms: inverted cone, columnar, and conical. 
 
 the roots visible above the ground? Compare dif- 
 ferent trees with reference to this characteristic. 
 
 Leaves. Stand under a trees and look up. Where 
 are the leaves most numerous? To what extent do 
 they overlap? Are they simple or compound? Com- 
 pare the upper and under sides. What are the 
 parts of one leaf? See Fig. 19. What form does 
 the petiole take where it is attached to the twig? 
 
TREE STUDIES 
 
 87 
 
 How are the leaves arranged on the stem with ref- 
 erence to each other ? What relation can you see 
 between the petiole and the large veins! Hold the 
 leaf between you and the light to see how numerous 
 the small veins are. Study the leaves on one twig 
 and note differences as to 
 size, shape, and length of 
 petiole. Can you see any 
 advantage to the leaves in 
 the different sizes of the 
 blades and the different 
 lengths of petioles ? If you 
 have a twig indoors lay it 
 down upon your desk allow- 
 ing the leaves to assume a 
 natural position. How does 
 this help you to solve the 
 problem? 
 
 Compare leaves of dif- 
 ferent species of the same 
 family, as those of different 
 maples, oaks or elms, and determine what character- 
 istics are similar and what are different. Make a 
 collection of all the different types of leaves you can 
 find. 
 
 Watch the trees frequently for a number of weeks 
 to find out what they do to get ready for the winter 
 season of inaction. What different colors do you 
 
 Fig. 19. Parts of a leaf: a, 
 Petiole; b, Blade; c, Midrib; 
 d, Veins; e, Margin. 
 
88 
 
 STUDIES IN SCIENCE 
 
 find? W T hat color is most prominent? What trees 
 have the most brilliant reds? Which ones are chiefly 
 yellow? Which dull purple or brown? When the 
 leaves have fallen, examine the 
 spots on the twigs from which 
 they dropped and try to decide 
 what caused them to drop off. 
 
 Twigs. Look carefully at a 
 twig and make a list of every- 
 thing that you see. This study is 
 best made after the leaves have 
 fallen. See Fig. 20. How can you 
 tell exactly where the leaves were 
 located? Describe a leaf scar. 
 Compare the scars on the older 
 parts of the twigs or branch with 
 those of this year. 
 
 Classify the buds as to position 
 on the twigs and their relation to 
 each other. How do they differ 
 as to shape and size ? What will 
 each kind of bud produce ? If you 
 do not know, wait until spring to 
 solve the problem. Examine a 
 bud very closely and describe 
 what you see. What is on the out- 
 
 ticles; d Leaf bud; e, gide | The i ns i<}e? What is the 
 Flower bud. 
 
TREE STUDIES 89 
 
 value of the scales, the downy covering, or sticky 
 secretion! 
 
 How can you tell what part of the twig grew this 
 year! What makes this ring scar I How many 
 years' growth does your twig represent? 
 
 Compare the twigs of a number of different trees 
 with reference to the length of growth in one season, 
 the arrangement of buds, and the shape of leaf scars. 
 
 Fruit and seed. Make a list of all the trees you 
 can find that retain their fruit or seeds during the 
 fall or after the leaves have fallen. Describe the 
 different kinds of fruit. How many of them have 
 special adaptations for dissemination? Open up the 
 fruit in each case and find the seeds. 
 
 Make a list of everything you have discovered 
 that deciduous trees do to get ready for the winter 
 rest and for renewal of growth in the spring. 
 
 You will find the following outline helpful in keep- 
 ing a record of your tree studies. Do not think that 
 every item must be put in with your first observa- 
 tion. You may have to wait months to complete 
 the record. 
 
 OUTLINE FOR TREE STUDY 
 
 1. Name: 
 
 2. Shape: conical, broad conical, narrow conical, spherical, col- 
 umnar, inverted cone. 
 
 3. Method of branching: (a) excurrent. (Main stem may be 
 
90 STUDIES IN SCIENCE 
 
 traced from ground to top of tree) ; (b) deliquescent. (Main stem 
 breaks up into branches.) 
 
 4. Twigs: erect, drooping, slender, thick, graceful, stiff, etc. 
 
 5. Trunk or bole: color; surface, smooth, rough, scaly, furrows 
 or fissures, deep or shallow, ridges wide or narrow. 
 
 6. Leaves: arrangement, opposite or alternate; simple or com- 
 pound;, if compound, number of leaflets; oddly pinnate, evenly pin- 
 nate; special characteristics; shape, color, roughness, smoothness, 
 etc. 
 
 7. Flowers: date of flowering, kind: (a) perfect, both stamens 
 and pistil in one flower; (b) staminate, a flower with stamens and 
 no pistil; (c) pistillate, one with pistil and no stamens. 
 
 8. Fruit: date of maturing, kind. Seeds: kind. 
 
 9. Buds: arrangement, opposite or alternate, shape, color, 
 scales. 
 
 10. Remarks: value of tree for ornamental purposes. Other 
 uses, etc. 
 
 Charts and booklets. Make a set of tree charts, 
 or booklets. Each individual tree species repre- 
 sented on a chart or page should contain a leaf, the 
 fruit, seeds, and a twig in winter condition, a small 
 bit of bark and when possible a section of wood. 
 Cardboard or any stiff paper should be used, and 
 the specimens sewed on rather than pasted. In 
 regions where there are few trees, leaf charts may 
 be made. Group charts or pages to show family 
 relationship; that is, put together all the oaks, 
 maples, pines, etc. 
 
 Discussion. We may group our trees into broad- 
 leaf and narrow-leaf trees. The narrow leaves are 
 usually called needles. In the northern and central 
 states all broad-leaf trees are deciduous; that is, they 
 
TREE STUDIES 
 
 91 
 
 drop all of their leaves each year. Almost all of the 
 needle-leaf trees are evergreen. A few, however, 
 the larch and cypress, drop their leaves in the fall. 
 Some of the broad-leaf trees in the South retain their 
 leaves during the winter. 
 
 The shape of a tree depends largely upon the 
 method of branching and the number and character 
 of the twigs. A tree whose trunk breaks up into 
 
 Sugar or Rock Maple Norway Maple 
 
 Fig. 21. Sugar or Bock Maple and Norway Maple. 
 
 a number of branches has deliquescent branching; 
 one whose trunk extends up through the crown has 
 excurrent branching. 
 
 Some trees, as the maple, elm, and oak, have simple 
 leaves. Each blade is in one piece, although the 
 margin may be notched or lobed. Others like the 
 walnut, hickory and ash, have compound leaves; 
 
92 
 
 STUDIES IN SCIENCE 
 
 that is, the blade is divided into a number of small 
 leaves called leaflets. If the leaf has an odd number 
 of leaflets it is said to be oddly pinnate; if it has 
 an even number it is evenly pinnate. 
 
 As autumn advances you notice that the leaves 
 change color. This change comes because the leaves 
 are ceasing to work. Their chief work is to manu- 
 facture starch and other 
 foods. As this work 
 slowly stops the green 
 coloring matter changes 
 to yellow. The bright 
 reds and the dull 
 purples are produced 
 by certain chemical 
 changes that take place 
 in the tissues of the 
 dying leaf. Autumn 
 coloration then simply 
 tells you that the trees 
 
 Fig. 22. A compound leaf show 
 ing seven leaflets. 
 
 have shut down their starch factories and are getting 
 ready for the season of rest. You sometimes hear 
 people say that frost is the cause of autumn colora- 
 tion and the dropping of the leaves. You can 
 readily see from what you have learned that this 
 cannot be strictly true. The fact is that some 
 years the leaves are a brilliant color before we 
 
TREE STUDIES 93 
 
 have any frost. Early cold weather accompanied 
 by frost probably causes the leaves to stop their 
 work earlier in the season, and that is all that frost 
 has to do with it. Sometimes a heavy freeze comes 
 while the leaves on some trees are still active and 
 full of moisture. In that case they are simply killed, 
 which is shown by their withering. 
 
 The dropping of leaves comes, too, with the cessa- 
 tion of work. As you looked at a twig from which 
 the leaves had fallen, you found that no wound was 
 left, but that a layer of skin or thin bark had grown 
 upon the twig under the petiole. This layer severs 
 the petiole from the twig. The leaf may cling for 
 a time by the fibres, but a slight breeze, the weight 
 of raindrops, or even its own weight finally takes it 
 off. The fibers of some trees, as certain oaks, are so 
 firmly attached that the dry, dead leaves remain on 
 the twigs all winter. 
 
 In some ways the buds are the most important 
 things that are found on the twigs. Do you know 
 how early each season they make their appearance? 
 You will find this an interesting problem to solve 
 by observation next spring and summer. 
 
 The scales, downy coverings, and sticky secretions 
 protect the buds from mechanical injuries, but their 
 most important use is to prevent the evaporation of 
 water. During the winter very little moisture is 
 
94 STUDIES IN SCIENCE 
 
 taken into the tree through the roots. If the small 
 leaves and flowers in the buds were not protected 
 in some way, they would dry out and die. 
 
 If you watch the buds open in the spring, you will 
 find that usually the large ones on the twigs pro- 
 duce flowers, while the smaller ones produce a twig 
 with leaves. On some trees the leaf and flower buds 
 are combined. The lateral buds produce new twigs 
 and afterwards become the branches. The terminal 
 buds lengthen the branches. When the buds open 
 the scales drop leaving the ring scars. These scars 
 not only tell you where the buds were but also that 
 the scales are arranged in a series one above the 
 other. 
 
 The dots called len'ti-cels are tiny openings in the 
 bark, which when the twig is young allow the entrance 
 of air and probably the exit of waste products and 
 water. 
 
 Winter study. Do not stop the observation of 
 trees during the winter. This is one of the best 
 seasons to learn the typical forms, the branching, 
 color, and especially the twig and bud characteristics. 
 If you have never looked closely at trees during this 
 season, you will be surprised to find how individual, 
 how interesting, and how beautiful they are. 
 
WINTER STUDIES 
 
 CHAPTER V 
 SOILS 
 
 Material. Soil from gardens, fields and excava- 
 tions; a collection of pebbles, gravel, sand, silt and 
 clay; apparatus described in connection with experi- 
 ments. 
 
 Examine carefully a small quantity of soil that has 
 been taken from a cultivated field or a garden. Write 
 out a list of everything that you find. 
 
 Experiment. Place some of the soil in a large iron 
 spoon and hold it over the flame of an alcohol lamp 
 or gas burner. Heat it, stirring occasionally. What 
 happens? Set it away to cool and then examine it 
 again. What changes have taken place? Is the color 
 lighter or darker? What part burned up? What is 
 the material that is left? Before you try to answer 
 fully the last question examine a small portion of 
 sand, silt and clay. Look at each with a hand lens. 
 Which has the finest particles? What do you find in 
 the sand that is not present in the silt or clay? Take 
 a pinch of each between your thumb and finger and 
 rub them. How does the sand feel? The silt? The 
 
 95 
 
96 STUDIES IN SCIENCE 
 
 clay? Silt is often spoken of as clay. The yellow 
 clay of the Middle West is silt. 
 
 Heat a small portion of clay and of silt just as you 
 did the garden soil. Describe what takes place. After 
 they have cooled compare each with the burned gar- 
 den soil. Which one resembles it most? Can you 
 decide now what you got from burning the garden 
 soil? 
 
 Explanation. You no doubt found small bits of 
 roots and other parts of half -decayed plants in your 
 sample of soil. When you heated it the plant parti- 
 cles burned up and you had left what may be called 
 the foundation soil. What this foundation soil is 
 depends wholly upon the region from which it was 
 taken. It may be almost pure sand, pure silt, or some 
 kind of clay. The probabilities are that it is a mix- 
 ture of sand and silt or sand and clay. In any case 
 the soil mixture including the part that burned is 
 called loam. If it has a large per cent of sand it is 
 sandy loam; if there is much more silt than sand it 
 is silt loan; and if clay is the most prominent part it 
 is clay loam. 
 
 The part that burned, the organic matter, is called 
 humus. Leaf mold in the woods, the soft decaying 
 material under layers of pine needles, the remains of 
 an old straw stack, or well rotted stable manure, are 
 all types of humus. 
 
SOILS 97 
 
 You can find out by experiment something more 
 about the different kinds of soil. 
 
 Experiment. Pour the same amount of water into 
 each of three tumblers. Stir into one a tablespoonful 
 of sand, into another clay, and into the third silt. 
 Which settles to the bottom first? Keep a record of 
 the time that it takes for the water to become clear 
 in each glass. What does this tell you about the size 
 of the particles of each kind of soil! Which will 
 remain suspended longer in the water, coarse or fine 
 particles ? 
 
 Experiment. Put a spoonful of your garden loam 
 into a glass of water and stir as before. How does it 
 behave? After it has all settled, look through the 
 glass to determine whether or not the soil shows* 
 any layers of coarse and fine material. 
 
 Explanation. These experiments show that differ- 
 ent soils differ greatly with reference to the size of 
 the particles. You probably found that the sand 
 settled to the bottom before the silt or clay. This 
 is because the particles are larger and heavier. Dif- 
 ferent sands vary; some are coarse, some fine. Silt 
 is much finer than sand, but not as fine as clay. Dif- 
 ferent silts and clays vary just as sands do. Some 
 are very fine, others are coarse. 
 
 If your garden loam is a mixture of sand and clay 
 or silt, you probably found that it had settled in 
 
98 STUDIES IN SCIENCE 
 
 layers, the sand in the bottom and the clay or silt on 
 top. You probably found, too, that some of the 
 humus remained floating in the water long after all 
 the rest had settled. 
 
 Origin of soil. What is the origin of soil! Per- 
 haps you have already found out something about 
 this from your geography; if not, you can think out 
 part of the answer for yourself. 
 
 Collect from the bed of a stream, the shore of a 
 lake or wherever you can find them, a number of 
 pebbles. 
 
 Examine the pebbles you have brought in. Place 
 into groups those that seem to be of the same kind 
 of rock. How many different groups have you? Do 
 you find any that seem to be made of more than one 
 kind of rock? With a nail or other sharp instrument 
 scratch the different kinds. What do you determine 
 as to their relative hardness? 
 
 Compare your pebbles as to shape. Is there any 
 way to account for the fact that some are round 
 while others are flat? 
 
 Formation of pebbles. With a hammer break some 
 of the larger stones into small pieces. How do the 
 pieces differ from the pebbles? 
 
 Experiment. Can you think what has made the 
 pebbles so smooth? Fill a pint milk bottle about one- 
 third full of the broken bits of rock. Now pour in 
 
SOILS 99 
 
 water until the rock fragments are covered. Place a 
 cover on the bottle or hold your hand over the top 
 and shake vigorously. As the pieces of rock strike 
 against each other what happens? Continue shaking 
 them, off and on, for days. When you allow the bot- 
 tle to stand until the water is clear what do you find 
 in the bottom? 
 
 Explain why you find so many pebbles along 
 streams, and on the shores of lakes and rivers. If 
 you should follow a stream to its source in hills or 
 mountains, would you find as many small, smooth 
 pebbles and stones there? Why? 
 
 Experiment. Other agents that help to break up 
 rocks. Break up a piece of limestone or marble. Put 
 the pieces into a bottle. Into a half pint of water 
 put a tablespoonful of hydrocholoric acid and pour 
 over the pieces of stone. Shake thoroughly. Describe 
 what happens. 
 
 Discussion. From your observation and study you 
 have probably come to the conclusion that pebbles, 
 gravel, sand, silt and clay are all forms of broken and 
 ground up rock. Indeed, if you go back far enough 
 in the history of the earth you must think of a time 
 ages and ages ago when there was no soil on the earth, 
 nothing but solid rock, wrinkled and jagged with here 
 and there huge broken pieces. Little by little various 
 agents ground up the solid rock into finer and finer 
 
100 STUDIES IN SCIENCE 
 
 particles. One of the chief agents that helped to do 
 this was changes of temperature. When rocks are 
 heated by the sun they expand. When cooled they 
 contract. If the contraction takes place suddenly, 
 the rocks are likely to crack open. 
 
 Freezing is another important soil-making agent. 
 Water from rains or melting snow gets into cracks and 
 crevices of rocks and when it freezes it expands and 
 breaks the rocks. In the same way our soil in fields 
 and gardens is made finer during the winter by thaw- 
 ing and freezing. We have already found by experi- 
 ment that the rubbing together of stones through the 
 action of water is an important soil-making agency. 
 
 If you were to visit a stream whose source is in 
 mountainous regions, you would find near the source 
 large pieces of rocks that have been broken from the 
 hillsides and bluffs and have fallen into the stream. 
 These pieces are the beginnings of pebbles. They 
 are broken into smaller and smaller pieces by tumb- 
 ling over each other, by the action of frost, and by 
 rubbing together as they move farther down the 
 stream. After a long, long time the rough edges are 
 worn off and nothing is left but smooth stones or 
 pebbles. The worn off particles settle to the bottom 
 and form the sand or mud in the bed of the stream. 
 
 The pebbles found on the shores of lakes and seas 
 are made by the dashing of the waves back and forth 
 
SOSXA'' i/ 101 
 
 on the beach. The pieces of rock roll against each 
 other and the edges are worn off. Pebbles found 
 along shores are usually round, while those in streams 
 are flat. 
 
 The work of glaciers, the great ice sheets that 
 moved slowly over a great part of our country 
 thousands of years ago, accounts for much of our 
 fine silt and clay. The great boulders and pebbles 
 that we find scattered here and there over the prairies 
 are also due to glaciers. If you look closely you 
 may find scratches on some of these stones. As the 
 glaciers moved slowly over the land they picked up 
 pieces of broken rock and pebbles and carried them 
 along. Some of them passed over other rocks and 
 pebbles and left deep scars on them. 
 
 Your experiment with the acid and limestone shows 
 how rocks may be dissolved by chemicals carried in 
 solution in water. Plants themselves aid in making 
 soil. Certain plants that are called lichens will grow 
 upon solid rock. As they grow they give out an acid 
 that eats into the rock slowly softening it and chang- 
 ing it into fine soil. 
 
 Broken up rocks alone do not make soil. You found 
 in the soil of the garden and fields partially decayed 
 vegetation or humus. Humus is an essential part of 
 soil and is necessary to plant life. It is produced by 
 parts of plants slowly decaying in the soil where little 
 
102 ^^SfJXDBj^JN SCIENCE 
 
 oxygen can reach them. It may be increased in any 
 cultivated field by plowing under stubble, corn stalks, 
 grasses, clover, etc. Humus is dark in color, so a 
 black soil usually indicates an abundance of humus. 
 
CHAPTER VI 
 
 WATER IN SOIL 
 
 Material. Samples of the different kinds of soil 
 studied in the last chapter; five straight lamp chim- 
 neys; a rack or jars to hold them; tumblers. 
 
 Source of water in the soil. Water in the soil is 
 quite as necessary for plant growth as minerals from 
 the rock particles and the humus. Rain is the source 
 of all soil water; if you watch the rain during a 
 shower you will observe that some of it runs off the 
 ground, some stands in puddles, and some sinks into 
 the earth. 
 
 Ground water. All the water that goes into the earth 
 is called ground water. 
 
 Experiment. To determine what becomes of the 
 ground water. Place a layer of pebbles in the bottom 
 of a tumbler, cover with a piece of cloth and on top 
 of this place dry garden soil until it stands within 
 an inch of the top. Firm the soil by striking the 
 glass on the table. Pour some water on the soil a 
 little at a time and watch to see what it does. Con- 
 tinue to pour until water stands in the spaces among 
 
 the pebbles in the bottom of the glass. 
 
 103 
 
104 STUDIES IN SCIENCE 
 
 Explanation. When rain falls upon the ground it 
 does just what the water in the glass did. It perco- 
 lates slowly downward through the soil till it is 
 stopped by solid rock or by a layer of clay or by soil 
 already full of water. Now if rain continues the 
 water will fill all the spaces among the tiny particles 
 of soil until it finally stands on the surface of the 
 ground, for, while you cannot see them, soil is made 
 up of fine particles. Water that is found in the 
 spaces among the particles of soil is called free water. 
 Plants do not use free water. 
 
 The level at which free water stands in the soil is 
 called the ground water level or the water-table. 
 Perhaps you noticed when you poured water upon 
 the dry soil in your experiment that bubbles of air 
 came out as the water went in. When the spaces are 
 not filled with water they are full of air. 
 
 Capillary water. Examine some soil that is slightly 
 moist. This does not contain free water. 
 
 Experiment. Where is the water in this moist soil? 
 Tie a piece of thin cloth loosely over a tumbler; place 
 two or three small, smooth pebbles close together 
 on the top of the cloth. Pour some water over the 
 pebbles and let it drain down into the tumbler. Now 
 examine the pebbles. Describe what took place. 
 Where is the water in relation to the pebbles! 
 
 Explanation. The water that remains clinging to 
 
WATER IN SOIL 105 
 
 the pebbles is called film water because it forms a film 
 around the pebbles. In the same way moist earth has 
 a film of water around each tiny particle of soil. 
 This is known as capillary water. It is this water 
 that plants use. The free water must be drained off 
 to give the roots a chance to get the capillary water. 
 
 Experiment. Drainage. Tie a piece of cloth firmly 
 over the tops of each of five lamp chimneys. Put 
 sand into one, clay or silt in another, and loam in 
 another. In the fourth put a mixture of half sand 
 and half humus, either well rotted manure or leaf 
 mold. Into the last put a mixture of half clay and 
 La If harnus. Arrange a rack for the chimneys or 
 stand each one in a jar. Measure a definite amount 
 of water and pour it slowly into the sand. Note the 
 number of minutes required for the water to pass 
 through and drip into a dish or the jar. Keep a 
 record of the amount of water you pour in. Do the 
 same with all the other chimneys. Measure the 
 amount of free water that drips from each. Through 
 which soil does the water drain most readily! Which 
 one takes longest for the water to pass through? 
 Which soil retains the greater amount of water? 
 What is the effect of putting humus into sand? Of 
 putting it into clay? 
 
 Explanation. Your experiment shows that water 
 passes rapidly through sand but slowly through silt 
 
106 STUDIES IN SCIENCE 
 
 or clay. Humus in sand makes it retain more water 
 and drain less rapidly, while humus in clay has the 
 opposite effect. Humus then improves both of these 
 soils. 
 
 What method is used in your neighborhood to drain 
 the soil? If you live in the country find out how 
 your farm is drained. You may find an open ditch 
 or an underdrain. 
 
 Drainage is of advantage for several reasons: 
 1. The ground water level is lowered so that the 
 roots of plants go deeper into the ground. A deep 
 root system is of value to plants during the dry 
 season. 2. It gives an opportunity for air to reach 
 and fill the spaces near the surface, and plants need 
 air as well as water. 3. A well drained soil warms 
 earlier in the spring. Do you know why! A soil 
 full of water uses up heat in evaporating the moisture. 
 
 Underdrainage, where it can be practiced, is more 
 satisfactory than the open ditch. It does not waste 
 land since the soil over the tile may be cultivated. 
 It drains to a greater depth and thus makes it pos- 
 sible for the plants to produce a deeper root system. 
 See Fig. 23. 
 
 The value of drainage is not generally understood. 
 Where the land is not at all level, or where the soil 
 to a considerable depth is composed of sand or gravel, 
 drainage is not likely to be important, because the 
 
WATER IN SOIL 
 
 107 
 
 excess water runs away over the surface or settles to 
 a depth below the level of ordinary plant roots. 
 
 On the other hand, where the land is very low, or 
 very level over a considerable area, the soil is likely 
 to be saturated with water to a level somewhere near 
 the surface. For example, if one digs a hole he usually 
 has not to go down very far before he finds that the 
 water flows in and stands at a certain level in the 
 
 Fig. 23. Showing one important effect of drainage. 
 
 hole. This shows the level at which the soil at that 
 particular place is saturated with water. 
 
 In undrained land this water level varies in distance 
 below the surface of the soil according to whether the 
 season is dry or there is much rainfall. During the 
 wet season it is likely to be very near the surface, 
 perhaps not more than six, eight, or twelve inches. 
 See line a in Fig. 23. Plant roots do not thrive below 
 
108 STUDIES IN SCIENCE 
 
 this water level, because they cannot get air. More- 
 over, when the soil is thus saturated for a considerable 
 length of time it is cold and is likely to become sour. 
 Plants growing on soil of this kind do not thrive. 
 They commonly look weak and the leaves turn yellow. 
 Then if there is a period of drought the water level 
 may be considerably lowered in a short time. See line 
 b in the diagram. In such a case the plant roots are 
 not only left away above the water line, but the soil 
 is likely to bake and harden. 
 
 The other part of the diagram indicates that where 
 the soil is drained the water level is likely to be main- 
 tained at nearly all times at the level of the drain. 
 See line c. Under these conditions the plant roots 
 extend themselves far enough down in the soil to get 
 all the moisture they need. In addition to this the 
 soil above the water level in drained land never bakes 
 or hardens ; that is, it is always open and porous. The 
 plant roots grow more freely in it and the moisture is 
 drawn upward above the water level by the capillary 
 action in the soil quite uniformly at all times. 
 
 Irrigation. You may live in a region where irriga- 
 tion is necessary. All through the western states 
 there are large tracts where the annual rainfall is not 
 sufficient for the growth of plants. Here water is 
 brought from mountain streams or lakes through 
 tunnels or aqueducts. Usually small ditches several 
 
WATER IN SOIL 109 
 
 rods apart extend through the fields or orchards. 
 The owner controls the supply by opening a sluice 
 and allowing the water to run into the ditches and 
 flood the fields. 
 
CHAPTER VII 
 
 SOIL WATER AND PLANTS 
 
 Material. Seeds of oats, corn, radishes or other 
 plants; plates or boxes, a growing plant in a pot. 
 
 Experiment. Root-hairs. You know that plants 
 cannot live without water and you will be interested 
 in learning how they get water from the soil. Place 
 some seeds of radishes, oats, wheat, or corn on a plate 
 of moist sand or soil. Press them slightly into the 
 soil but do not cover. Turn a plate over them to keep 
 the moisture in. Watch them from day to day.. Do 
 not allow the soil to dry. Describe the roots and 
 root-hairs. On what part of the roots are the hairs 
 most numerous! On what part are there no hairs? 
 Place one of the plants on a piece of paper on your 
 desk for a short time. What happens to the hairs? 
 Watch the plants for several days to see whether any 
 of the hairs wither and die and whether new ones 
 continue to appear. (Refer to Fig. 8, page 33.) 
 
 Explanation. You found the delicate hairs grow- 
 ing all around the young roots. If these roots were 
 covered with soil, the root-hairs would penetrate the 
 spaces between the soil particles and come in close 
 
 no 
 
SOIL WATER AND PLANTS HI 
 
 contact with the films of water. The film or capil- 
 lary water passes through the thin walls of the root- 
 hairs. You may think this a slow process and it is, 
 but when you consider the thousands of root-hairs 
 on all the small roots of the growing plants you realize 
 that together they can take in a vast quantity of 
 water. The process by which the water passes 
 through the thin membranes of the root-hair is called 
 osmosis. The same process takes place in your own 
 body when digested food is absorbed by tiny capil- 
 laries which surround the digestive tract, and is car- 
 ried into the blood to be distributed to all parts of 
 the body. 
 
 The water that plants take into their roots is not 
 pure water but has in it certain minerals that the 
 plants use in their growth. 
 
 Experiment. To distinguish soluble and insoluble 
 substances. 
 
 1. Into a half glass of warm water slowly stir some 
 fine salt. Continue to put in salt until it begins to 
 settle to the bottom of the glass. What became of 
 the salt that disappeared! Drain off the clear water, 
 put it into a pan and place it on a stove or over 
 an alcohol lamp till it is all evaporated. What is left 
 in the pan! How is salt commonly obtained! Make 
 the same experiment with sugar and saltpetre. 
 
 2. Into a half cup of water stir some chalk dust, 
 
112 STUDIES IN SCIENCE 
 
 lime, or sulphur. Do any of these act as the salt and 
 sugar did? How do you account for the difference? 
 
 Explanation. The salt disappeared because it was 
 dissolved by the water and changed into a liquid. 
 The chalk or sulphur will not dissolve in water so 
 it remains in the solid form. A substance that dis- 
 solves as the salt did is said to be soluble in water. 
 Chalk and sulphur are insoluble in water. You can 
 see from this that all soil minerals that enter the 
 root-hairs must be soluble in water. 
 
 All seed plants need ten different elements if they 
 are to grow and produce fruit. Seven of these are 
 obtained from the soil. They are nitrogen, phos- 
 phorus, potassium, calcium, sulphur, iron and mag- 
 nesium. The last three are so abundant in soils and 
 are used in such small quantities that we do not need 
 to concern ourselves about them. Calcium is abund- 
 ant in most soils but is lacking in a few regions. The 
 first three elements, nitrogen, phosphorus, and potas- 
 sium, are not abundant in most soils and are used 
 in comparatively large quantities; hence they are 
 frequently lacking in fields that have crops growing 
 in them year after year. When we speak of "worn 
 out soil," we usually mean that it lacks one or two 
 of these elements. 
 
 Good farmers and gardeners try to keep their soil 
 fertile by the use of fertilizers, by plowing under 
 
SOIL WATER AND PLANTS 113 
 
 plenty of vegetation to make humus, and by good till- 
 age to insure a deep, rich, mellow soil-home for the 
 plants. 
 
 The constant supply of water and mineral food. 
 How to keep a constant supply of capillary water 
 for the growing plants in regions that depend entire- 
 ly upon rain is a problem of much interest. 
 
 Experiment. What are all the ways in which 
 capillary water is taken from a field or garden in 
 which plants are growing? 
 
 Fill a tumbler with moist soil. Invert over it 
 another tumbler. Set it aside for twenty-four hours 
 and then examine. What do you find on the inverted 
 glass! Where did the moisture come from? 
 
 This shows that moist soil is constantly losing 
 some of its moisture by evaporation. You know also 
 that the plant itself is using up moisture. If this 
 continues for days and there is no rain, the soil will 
 become dry far below the surface. 
 
 Experiment. Capillarity. Tie a piece of cheese 
 cloth over one end of a long glass tube, open at both 
 ends, and fill it with dry soil. Stand the tube in a 
 jar containing about an inch of water. What hap- 
 pens? Leave it for several days to determine how 
 high the water will go in the soil. You can make 
 some other experiments to illustrate the same prin- 
 ciple. Tie a piece of an old towel to a pencil and 
 
114 STUDIES IN SCIENCE 
 
 let the free end dip down into a jar which contains a 
 small amount of water. What takes place? 
 
 The same thing takes place in the soil and in the 
 towel. The water slowly rises. This is caused by 
 what is known as capillarity or capillary attraction, 
 and always occurs when liquids come in contact with 
 fibrous or porous materials. The ordinary lamp wick 
 which conveys oil from the bowl of the lamp to the 
 top of the wick is a good example of capillary 
 attraction. 
 
 Experiment. Capillarity found in different soils. 
 Fill several glass tubes or the lamp chimneys used 
 in the drainage experiment with different kinds of 
 soil. Place the lower ends in water, and determine 
 which soil lifts the water to the highest point by 
 capillary attraction. 
 
 As water is used up by plants in the fields, more 
 is constantly moving upward from the free water 
 below. If the weather is very warm, much of the 
 water that moves upward may be lost to the plants 
 by evaporation, so another problem of the gardener 
 and farmer is how to prevent this loss. 
 
 Experiment. Conserving soil moisture. Put equal 
 amounts of soil into two pans of the same size. Firm 
 the soil by gently jarring the pans upon the table. 
 Pour equal amounts of water over each. Weigh each 
 pan and set them side by side. Thoroughly stir the 
 
SOIL WATER AND PLANTS 115 
 
 upper inch and a half of soil in one pan every day 
 keeping the layer on top very fine. Leave the other 
 pan undisturbed. Weigh them at the end of three 
 or four days, and again at the end of a week. Which 
 one has lost more weight! Explain why the stirring 
 of the soil prevents evaporation of water. 
 
 As long as the soil is left alone the water moves to 
 the surface by capillarity and evaporates. Then 
 cracks are likely to come in it which allow the air 
 to penetrate to quite a depth and aid in evaporating 
 the water. The stirring of the soil stops the flow of 
 water to the surface. It is like breaking off the ends 
 of tubes. This keeps the water in the soil. The layer 
 of dry soil is called a soil mulch. You see how 
 important it is to cultivate the top layer of soil in 
 your garden or fields during hot dry weather. 
 
 Experiments. What becomes of all the water that 
 plants take from the soil? 
 
 (a) Procure a small plant growing in a flower 
 pot. Tie a piece of writing paper over the top of 
 the pot. To do this slit the paper to the center, then 
 cut out a round hole just the size of the plant stem 
 and slip the paper around the plant. Place a glass 
 jar over the plant and set it in the window. Look at 
 it the next day. What has happened? Where did 
 the moisture come from that settled upon the glass? 
 
 (b) Allow a plant growing in a flower pot to 
 
116 STUDIES IN SCIENCE 
 
 remain a number of days without water. A small 
 coleus or foliage plant is good for this experiment. 
 What change occurs in the appearance of the plant? 
 Pour water over the soil thoroughly soaking it. Keep 
 a record of the number of minutes till the drooping 
 leaves and stems revive. What now holds the plant 
 rigid and erect? 
 
 Explanation. The moisture that gathered upon 
 the glass in experiment (a) came from the leaves and 
 stems of the plant. It was given out in the form of 
 vapor and condensed upon the cool glass. It could 
 not come from the soil because that was covered up, 
 All living, working plants are constantly evaporating 
 water. The process is called transpiration. 
 
 The second experiment tells you that one use of 
 water in growing plants is to keep them rigid and 
 erect. When too much water is evaporated com- 
 pared to the amount taken in the plant wilts. 
 
 In order that plants may obtain from the soil all 
 the water and minerals they require for their work, 
 farmers and gardeners must treat the soil so that 
 it will produce the best yield of crops now, and at 
 the same time insure the production of good crops 
 in all the years to come. To do this a number of 
 things are necessary: 
 
 1. Tillage. This includes two processes, breaking 
 or plowing, disking and harrowing, in preparation 
 
SOIL WATER AND PLANTS 117 
 
 for the seed, and cultivation when the crop is grow- 
 ing. Good tillage increases the depth of the soil. 
 This means that the plowing must be deep. If only 
 the upper three or four inches are turned over the 
 surface of the soil will soon become depleted of its 
 mineral plant-foods. Moreover, the lower layer of 
 soil will become packed and sour and utterly unfit 
 for the plant roots. Tillage also aids in the saving 
 of moisture. How? Think of your experiment with 
 soil mulch. It also loosens the soil so that it will 
 hold more air and allow better ventilation. It kills 
 out the weeds and thus prevents a loss of plant-foods 
 to the crop. It turns under vegetation and thus 
 increases the amount of humus in the soil. 
 
 2. Drainage. We have already seen that drainage 
 is of advantage in lowering the ground water level 
 and in keeping the soil surface open for the entrance 
 of air. 
 
 3. Rotation of crops. Agriculturists are coming to 
 believe more and more that growing the same kind of 
 crop in a field year after year will result in absolute 
 ruin to the soil. One reason for this is that certain 
 crops use more of one kind of plant-food in the soil 
 than others do. After a number of years the soil 
 is so lacking in this particular compound that it is 
 difficult to grow any kind of a crop on it. 
 
 When legumes are rotated with other crops the 
 
118 STUDIES IN SCIENCE 
 
 supply of nitrogen is kept constant in the soil. Bota- 
 tion also gives an opportunity to kill out weeds that 
 are likely to persist if the same crop is grown year 
 after year. It also helps to get rid of certain insect 
 pests. Every farmer must settle for himself the crops 
 that are to be rotated; but he should adopt a definite 
 system of plant rotation and follow it in regular 
 order year after year. A common rotation in the 
 corn belt is oats, clover, corn. 
 
 4. Fertilizer's. Fertilizers are of two kinds, nat^ 
 ural and commercial. Of the first barnyard manure 
 is the best. It not only increases the humus of the 
 soil, but it is rich in the three elements that soil needs, 
 nitrogen, phosphorus and potassium. Green manure 
 is another natural fertilizer. This means the plowing 
 under of green crops. All the legumes as clovers, 
 cow-peas and alfalfa, when plowed into the soil are 
 green manures. Bye and rape are also used for this 
 purpose. 
 
 Commercial fertilizers, as the name implies, are 
 materials that are bought and put in the soil. To 
 supply phosphorus, bone-meal and rock phosphate 
 are used. For nitrogen, Chile saltpetre (nitrate of 
 soda), dried blood, and sulphate of ammonia are 
 used. For potassium, different forms of potash are 
 used. 
 
 If calcium is lacking in soil lime should be used. It 
 
SOIL WATER AND PLANTS 119 
 
 is also used to sweeten sour soil. When soils become 
 sour, the bacteria cease to change the organic material 
 into humus. Plants do not thrive well in sour soil. 
 Any soil that has been used for a long period of 
 years is likely to become sour and is improved by 
 an application of lime. 
 
 Look up carefully what methods of rotation are 
 practiced in your community; also what special means 
 are taken to maintain the fertility of the soil. 
 
CHAPTER VIII 
 
 THE WORK OF PLANTS 
 
 Materials. Potatoes, grains of corn, flour, oat- 
 meal, corn-starch, seeds of sunflower, cotton, flax, 
 squash or pumpkin, solution or tincture of iodine. 
 
 Plants use some, of the water that they obtain from 
 the soil in the manufacture of food and other 
 products. 
 
 Experiments. What foods and products do plants 
 manufacture? Scrape as fine as possible one or two 
 potatoes. Place the scrapings in a tumbler of water, 
 stir thoroughly two or three times, and allow to 
 settle. Examine next day. What do you find in 
 the bottom of the tumbler? Drain off all the water 
 and potato pulp, leaving nothing but the starchy 
 looking mass in the bottom. Boil some water over 
 the alcohol lamp and pour a little of this into the 
 tumbler, stirring until the mixture thickens. This 
 resembles ordinary laundry starch. 
 
 There is a chemical test, however, that will prove 
 beyond doubt that you have starch in the tumbler. 
 Place a small quantity of the cooked starch on a plate 
 or saucer, and then put two or three drops of iodine 
 
 120 
 
THE WORK OF PLANTS 121 
 
 on it. What is the effect of iodine on the substance? 
 The blue color indicates the presence of starch. The 
 darker the blue the more starch there is present. 
 Sometimes it is almost black. Place a drop of iodine 
 on a slice of raw potato. Does it show as much 
 starch as that which is cooked? The reason the lat- 
 ter shows more starch is that the boiling water causes 
 the walls of the starch granules to burst open and 
 the iodine can act more readily upon the starch. 
 
 Pour a little boiling water over some flour and 
 test it for starch. Make the same experiment with 
 corn-meal, oatmeal and corn-starch. 
 
 Soak some grains of corn for forty-eight hours, or 
 for an hour in hot water. At the pointed end of the 
 grain find the tip cap. Remove this. The cap may 
 be lacking on some grains, having been left on the 
 cob. With a knife or pin remove the hull. You will 
 see that the grain under the hull is covered with a 
 thin, smooth material that with care may be scraped 
 off with a knife. This is called horny gluten. Now 
 dig out the germ or embryo. This is the light gray, 
 oval shaped portion that fills up the groove in the 
 soaked grain. 
 
 Split open the remaining part of the grain. How 
 many kinds of material are left? Place by itself the 
 white granular material found near the crown of 
 the grain. Add to it the same kind of material found 
 
122 STUDIES IN SCIENCE 
 
 near the tip. Put the hard, solid looking substance 
 in another pile. You now have six different sub- 
 stances found in your grain of corn. Test each of 
 these with iodine as you did your potato starch and 
 flour. It is best to crush them as much as possible 
 before putting on the hot water. What part shows 
 the most starch! It is probable that the soft granular 
 part will turn the darkest blue. This part is known 
 as crown starch. The solid, hard part, if thoroughly 
 boiled, will show some starch. This is called horny 
 starch. What parts do not contain starch! This 
 means, of course, that there must be some substances 
 other than starch in the grain of corn. 
 
 Eemove some fresh embryos from soaked grains 
 and crush them on a sheet of white writing paper. 
 Hold the paper between you and the light. What do 
 you see! The grease spot indicates the presence of 
 oil or fat. Test other seeds in this way for oil, such 
 as sunflower, squash, pumpkin, flaxseed, etc. 
 
 Put a small pinch of each of the following on a sheet 
 of paper; flour, corn-meal, any cereal breakfast food, 
 buckwheat, and ground coffee. Place the sheet in a 
 hot oven and keep it there a few minutes. What 
 evidence is there that these things contain oil! Name 
 some plants whose seeds contain so large a percentage 
 of oil that it is extracted and used for commercial 
 purposes. 
 
THE WORK OF PLANTS 123 
 
 Discussion. Besides starch and oil, plants contain 
 other substances. 
 
 The embryo of the corn is composed largely of pro- 
 tein. Another substance in plants is sugar. A sweet 
 potato tastes sweeter than a white potato because it 
 contains more sugar. Name other plants that have 
 sugar in them. From what plants is the sugar of 
 commerce obtained! All starch found in plants is 
 changed into sugar before it can be absorbed by 
 plants or animals. Starch is insoluble in water, and 
 all substances absorbed by living bodies must be 
 soluble. 
 
 The corn hulls are composed chiefly of a substance 
 called cellulose. Cellulose is found in all plants 
 It is the material that gives strength and firmness 
 to the different parts. It is found in the cell-walls, 
 in fibers of stems, roots, and leaves, as well as in 
 fruits and seeds. It is harder and thicker in some 
 parts of the plant, as in the stems, husks and roots, 
 than in others. The fibers of cotton, hemp, and flax 
 are made chiefly of cellulose. Soak some newspapers 
 or writing paper in water till all the sizing is washed 
 out. The pulp that remains is almost pure cellulose. 
 Much of our paper is made from wood pulp; that is, 
 from the cellulose of the woody stems of trees. 
 
 Where do the plants get all of these substances? 
 They manufacture them. All plants that have green 
 
124 STUDIES IN SCIENCE 
 
 leaves or green coloring matter in any part manu- 
 facture starch, sugar and other products. 
 
 You may think of plants, then, as factories, with 
 machinery, power, and raw materials. The raw 
 materials are found in the air, soil, and soil-water 
 about the plant. They are found in the form of 
 chemical compounds which the plants take in and 
 use. You may not know what a compound is. Water 
 is an excellent example. It is formed by the union 
 of two elements, oxygen and hydrogen. Both of 
 these are invisible gases which do not at all resemble 
 water. An element is a substance that so far as 
 chemists know cannot be separated into other sub- 
 stances. There are between seventy and eighty ele- 
 ments known. All other things in the world are 
 compounds, formed by the union of two or more ele- 
 ments. Just to mix elements together will not make 
 a compound. They must unite in definite proportions. 
 In order to understand what we mean by this you 
 must know that everything in the world is made up 
 of very small particles called molecules. The mole- 
 cules are so small that they cannot be seen by the 
 most powerful microscope. Each molecule is made up 
 of still smaller particles called atoms. Now, when a 
 chemical union takes place a certain number of atoms 
 of one element unite with a certain number of atoms 
 of another element or elements and make a molecule 
 
THE WORK OF PLANTS 125 
 
 of a new substance which is a compound. In water 
 two atoms of hydrogen unite with one atom of oxygen ; 
 hence we use the symbol H 2 to stand for water. 
 
 Chemical unions are taking place constantly in the 
 world of nature. In plants, chemical combinations 
 take place which result in the plant products you 
 have found. Starch is a combination of oxygen, 
 hydrogen and carbon. The symbols for these elements 
 are 0, H and C respectively. Proteid is a combina- 
 tion of carbon, hydrogen and oxygen, with nitrogen, 
 sulphur, phosphorus, and often other elements. 
 
 The plant gets its oxygen and hydrogen from the 
 water which it absorbs through its root-hairs. It 
 gets carbon from the air, not as an element but the 
 compound that you know, carbon dioxide. Its symbol 
 is C0 2 . This tells you that one molecule of carbon 
 dioxide is made by the union of one atom of C and 
 two of 0. 
 
 The work of manufacturing starch takes place in 
 the leaves or other green parts of plants. 
 
 Examine a leaf of any plant. Hold the leaf between 
 you and the light. What do yon see in it? How are 
 the veins arranged in a bean leaf, maple, sunflower? 
 These are net-veined leaves. How are the veins 
 arranged in a corn leaf? In grass? These are parallel 
 veins. What is the use of the veins? One apparent 
 use is to hold the blade spread out to the light. 
 
126 
 
 STUDIES IN SCIENCE 
 
 Place a twig with growing leaves in a tumbler of 
 water colored with red ink. After twenty-four hours 
 examine the petiole and the veins. The red ink in the 
 veins tells you that they carry water to all parts of 
 the leaf. 
 
 Procure a thick leaf, as live-for-ever, tulip, or hepat- 
 
 Fig. 24. Cross section of a leaf, showing cell walls, chlorophyll 
 bodies, and stomata, or breathing pores. 
 
 ica, and peel off a little of the skin or epidermis. 
 You can remove a little of the covering from a thin 
 leaf, enough to see that the entire leaf is covered 
 with a thin, almost transparent skin. What is under 
 the skin! This green granular mass is largely made 
 up of a substance called chlorophyll. 
 
 If you could see a cross-section of a leaf highly 
 magnified you would find it built up of cells. Each 
 
THE WORK OF PLANTS 127 
 
 cell lias a thin wall, contains green, roundish bodies 
 called chlorophyll bodies, and a mass of colorless 
 protoplasm. These form the machinery that manu- 
 facture plant-food. But just as any machinery must 
 have power to make it run, so must the machinery 
 of the leaf. What is the power? 
 
 Experiment.* Fill a box or dinner plate with soil 
 and sow some oats or wheat seeds. After the grains 
 have sprouted cover one-half the plants with a box 
 or tin can. Give all the plants the same amount of 
 water. After a week compare the plants grown under 
 cover with those grown in the light. What do the 
 former lack? What is your conclusion as to the abil- 
 ity of the plants to make chlorophyll without the aid 
 of light? 
 
 Discussion. Eecall the color of grass that has been 
 covered with a board, or the color of potato sprouts in 
 a cellar. Without light plants cannot make chlorophyll, 
 and without chlorophyll no starch can be made. The 
 light is the power that runs the machinery, but the 
 chlorophyll is the connecting link between the power 
 and the machine. In some way it succeeds in bring- 
 ing them together so that they are able to carry on 
 their work. 
 
 You remember that starch is made out of oxygen 
 and hydrogen from water and carbon from air, and 
 
 *This experiment should be started a week before time for the 
 
 lesson. 
 
128 STUDIES IN SCIENCE 
 
 that proteids contain these three elements with the 
 addition of nitrogen, sulphur, phosphorus, etc., which 
 come from the soil. 
 
 The leaves take in carbon dioxide through their 
 stomata, which are small openings in the epidermis. 
 What must be done with this compound before the 
 plant can use the carbon? It must be separated into 
 its elements, oxygen and carbon. The protoplasm 
 decomposes the carbon dioxide and uses the carbon. 
 It throws the oxygen back into the air. Therefore, 
 when a plant is actively engaged in manufacturing 
 starch it is taking carbon dioxide from the air and 
 giving out oxygen. Why cannot this process be car- 
 ried on during the night? 
 
 What do the plants do with the starch, proteids, 
 and oils that they make? The starch, by a process 
 something like digestion in our bodies, is changed 
 into sugar, and this and the other foods are con- 
 veyed in liquid form from the leaves to all parts 
 of the plants, where they are used in the growth of 
 these parts. 
 
 Do plants grow at night? Measure some of your 
 corn or other plants at night and again in the morn- 
 ing and see how much they have grown. While plants 
 cannot make food at night, they can use the food 
 they have made during the day for growth during the 
 night. Some of the food that is made is not used at 
 
THE WORK OF PLANTS 129 
 
 once but is stored away for future use in roots, stems 
 and seeds. 
 
 Plants need something besides food in order to live 
 and grow. They are like animals in this respect. 
 They must have air to breathe as well as food to 
 eat. They cannot live without oxygen any more than 
 you can. They carry on respiration at all times just 
 as you do. Not only the leaves but the stems and 
 roots need oxygen. The oxygen is taken into the 
 cells and unites with the carbon and other elements 
 giving the plant its energy. Waste products, C0 2 
 and moisture are thrown out into the air. 
 
 You must not confuse the two great processes that 
 plants perform. In making starch plants take C0 2 
 from the air and give out oxygen. In respiration 
 they take oxygen from the air and give out C0 2 . 
 The fact is that much more C0 2 is used in the manu- 
 facture of food than oxygen in the process of respira- 
 tion, so that actively working plants give out much 
 more oxygen than they take in. These two processes 
 go on at the same time during daylight just as diges- 
 tion and breathing go on in your body without inter- 
 fering with each other. 
 
CHAPTER IX 
 
 FOOD AND HEALTH 
 
 The foods that plants make feed many of the ani- 
 mals of the world including man. Since this is true 
 you will readily see why the human body is com- 
 posed of precisely the same elements that plants use 
 in their food. 
 
 Classes of food. We group foods according to the 
 elements they contain as follows : (1) carbohydrates, 
 which are starches and sugars. The term tells you 
 that the elements composing them are carbon, hydro- 
 gen and oxygen. A chemical compound whose name 
 ends in the syllable ate always has oxygen as one of 
 its elements. (2) Proteids, which contain carbon, 
 oxygen, hydrogen, nitrogen, sulphur, and phosphorus. 
 (3) Fats, which are composed of carbon, oxygen, and 
 hydrogen, but these elements are combined in different 
 proportions from those in starch. 
 
 Carbohydrates. Make a list of all the sources of 
 starch that you know. Do the same for sugar. You 
 will find that you have a long list. All the cereals, 
 as wheat, corn, oats, rice, etc., and the vegetables, as 
 potatoes, sweet potatoes, and fruits, have starch or 
 
 130 
 
FOOD AND HEALTH 131 
 
 sugar as a large part of their composition. The chief 
 value of carbohydrates in your body is to produce 
 heat and energy. From your study of oxidation you 
 know that this process takes place in the cells of 
 your body. 
 
 Proteids. All grains, especially their embryos, con- 
 tain some proteid. Beans and peas have a larger 
 percentage of proteid than other vegetables. All 
 other vegetables and fruits have small amounts. Most 
 of the proteid foods are obtained from animals. All 
 lean meat is largely proteid. The white of egg, milk, 
 cheese and fish are all proteid foods. Proteid is the 
 tissue builder of the body. It alone contains nitro- 
 gen, the element which is necessary in the making of 
 protoplasm. There can be no building of new cells 
 or repairing of old ones without proteid. The mus- 
 cles and other organs are constantly wearing out and 
 must have this kind of food to replace them. 
 
 Fats. Make a list of the sources of fats or oils and 
 the foods in which these are found. You probably 
 have in your list fats of animals and butter fat from 
 milk, as well as vegetable oils from cotton seed, olive 
 seeds, corn, etc. Fats are heat making foods and like 
 carbohydrates they produce energy. Fat which is 
 not used at once is stored in the body for future use. 
 During an illness people become thin and wasted be- 
 cause their bodies have had to use up all the surplus 
 
132 STUDIES IN SCIENCE 
 
 store of fat. Now since each of the three great classes 
 of foods, proteids, fats and carbohydrates, has its 
 special use in the body, you can see that we must have 
 some of each of these foods daily in order to keep the 
 body in good condition. Some people eat too much pro- 
 teid, others not enough. Too much proteid may 
 cause diseases of the kidneys, because these are the 
 organs that get rid of the waste from nitrogenous 
 foods. Too much fat and carbohydrate may result in 
 the storing up of so much fat that it is injurious to 
 the body. 
 
 Cooking. Most foods must be properly cooked in 
 order to be wholesome. Cooking produces chemical 
 changes in many foods and gives them a better flavor. 
 In most cases it makes foods easier to digest and 
 helps to kill off dangerous bacteria that may be in 
 them. The method of cooking has much to do with 
 the wholesomeness of foods. Roasting or baking 
 meat is much better than frying. Few vegetables, 
 even potatoes, should be fried ; instead they should be 
 baked, creamed or scalloped. Fried foods are the 
 cause of many cases of indigestion and poor health, 
 because, in the process of frying, the food becomes 
 coated with a hard layer of fat which must be dis- 
 solved before digestion can take place. Starchy 
 foods should be, cooked thoroughly so that the grains 
 of starch will be whollv softened. Proteids should 
 
FOOD AND HEALTH 
 
 133 
 
 as a rule be cooked slowly and should not be over- 
 done. 
 
 Digestion. Foods to be of value in the body must 
 be changed into liquid forms so that they may be 
 taken into the blood and carried to all parts of the 
 body. This process is called 
 digestion. It begins in the 
 mouth where the teeth break 
 up solid particles into small 
 bits. Besides this mechanical 
 change in the mouth, the saliva 
 acts chemically upon starch 
 changing it to sugar. When the 
 food reaches the stomach a 
 fluid called gastric juice is 
 poured upon it. This acts 
 chemically upon the proteids 
 changing them to another sub- Fig. 25. The digestive 
 
 mi tract: A, Mouth: B. Phar- 
 
 stance called peptones. The yn x; c, Esophagus; D, Dia- 
 food then passes on into the phragm; E ' Stomach; F ' 
 
 small intestine where several 
 
 Small intestine; G and H, 
 Colon; I, Eectum; J, Ap- 
 pendix. Transverse colon 
 
 other juices act upon it to finish is cut out - 
 the digestion. These are the pancreatic juice, which 
 comes into the intestine from the pancreas, the bile, 
 which comes from the liver, and some juices that pour 
 out of the walls of the intestine. By the time these have 
 acted upon the foods, the starches are all in the form 
 
134 
 
 STUDIES IN SCIENCE 
 
 of liquid sugar, the fats are broken up into tiny drop- 
 lets, and the proteids have all been changed to pep- 
 tones. The digested food is now in a condition to be 
 absorbed into the blood. 
 
 The lining of the small intestine is thickly covered 
 
 with tiny finger-like projec- 
 tions called villi, about as 
 close together as the nap on 
 felt or velvet. In each villus 
 is a little tube called a lacteal 
 which takes up the fat drop- 
 lets. There are also tiny 
 blood tubes in the villi which 
 take up the sugars and pep- 
 tones. The process by which 
 these liquid foods enter the 
 blood is precisely the same 
 as that by which the soil- 
 water enters the root-hairs 
 of plants, and is called 
 osmosis. 
 
 The fats are carried into a 
 large tube called the thoracic duct. This empties into 
 a vein near the collar bone, and this in turn empties 
 into a large vein which enters the right auricle of the 
 heart. The sugar and peptones pass into the blood of 
 a large vein which empties first into the liver. From 
 
 - LONGITUDINAL 
 
 Z SECTION OF 
 
 5 THE SMALL 
 
 D INTESTINE 
 
 o 
 
 i. 
 
 c 
 
 Fig. 26. A cross-section 
 of the wall of the small in- 
 testine magnified. 
 
FOOD AND HEALTH 135 
 
 here the blood goes through other veins to the right 
 auricle of the heart. Then it is sent to the lungs to get 
 a supply of oxygen, after which it returns to the heart 
 to be distributed throughout the body. 
 
 Hygiene of eating. If the food that you eat does 
 for you all that it should, you must observe certain 
 rules and regulations. First of all, you should chew 
 your food thoroughly. 
 
 One reason for thorough chewing is that it gives an 
 opportunity for a larger amount of saliva to mix with 
 the food and help to change the starch to sugar. The 
 other reason is that by breaking up the foods the gas- 
 tric juice in the stomach has a better opportunity to act 
 upon the proteids. 
 
 A second rule to observe is to eat regularly, that 
 is, eat at meal time and not between meals, unless you 
 are really hungry. If you have an early breakfast 
 and become very hungry before the noon meal, form 
 the habit of eating a small amount or drinking a 
 glass of milk about the middle of the forenoon. 
 Avoid eating candy, nuts, ice cream, etc., between 
 meals. Such things are best eaten as desserts of the 
 noon or evening meals. 
 
 Third, eat plenty of vegetables and fruits and not 
 much meat. Meat once a day is enough for any 
 healthy person. 
 
 Fourth, avoid stimulants of all kinds. Tea and 
 
136 STUDIES IN SCIENCE 
 
 coffee are not good for children. Alcoholic drinks 
 are generally injurious to health and rarely do any 
 good even when used as medicine. Everyone knows 
 how harmful they are. Patent medicines should also 
 be avoided. They are the source of much trouble in 
 the digestive organs. Medicine should be taken only 
 under the advice of a physician. 
 
 The teeth. If you examine your mouth in the mir- 
 ror you will find that you have in the. back part of 
 your jaw on each side, two or three broad, flat teeth. 
 These are called molars and their sole purpose is to 
 crush and grind up the solid food till it is reduced to a 
 pulp. Most people do not get the last molars, known 
 as the wisdom teeth, until they are from sixteen to 
 twenty years of age. In front of the molars on each 
 side are somewhat smaller teeth which also aid in 
 grinding. These are called bicuspids. In front of 
 the bicuspids are the sharp tearing teeth called 
 canines, and in front of these the two cutting teeth 
 called incisors. 
 
 Care of teeth. To keep the teeth in good condition 
 is a prime requisite to good health. Teeth that are 
 not kept clean serve as a lurking place for all sorts 
 of disease bacteria. If particles of food are left in the 
 mouth, around and between the teeth, they form an 
 excellent place for bacteria to grow and multiply. 
 Physicians believe they have good evidence that the 
 
FOOD AND HEALTH 137 
 
 ill health of many people may be traced directly to 
 teeth that are in bad condition. 
 
 The teeth should be brushed at least once every 
 day, better twice. The mouth should be rinsed thor- 
 oughly with water after each meal. A dentist should 
 be visited at least once a year, better twice, so that 
 he may detect any evidence of decay in the teeth and 
 attend to the matter at once. Thousands of young 
 people through lack of care lose second teeth that 
 could easily be saved for service and beauty during 
 many years. 
 
 Care of foods. Foods should be so cared for that 
 there may be little danger of spreading disease 
 through them. Foods that are exposed to dust in 
 stores or on the street should be thoroughly washed 
 before eating, especially those that are eaten raw. Ves- 
 sels in which foods are kept should be carefully 
 washed and sterilized with boiling water, and occa- 
 sionally left standing out in the hot sun. 
 
 People who cook food should use the greatest care 
 to cleanse their hands and nails perfectly before they 
 handle the food. Under no consideration should one 
 who is waiting on a sick person go into the kitchen 
 to cook without first washing his hands in a weak 
 solution of cabolic acid or other disinfectant. 
 
 Food should be kept from spoiling by keeping out 
 bacteria as much as possible; that is, by cleanliness, 
 
138 STUDIES IN SCIENCE 
 
 and by keeping the foods cool so that bacteria will 
 not grow and multiply in them. 
 
 All the people in a community who are thoughtful 
 about health conditions should cooperate to see that 
 stores and markets in which food is sold are kept 
 absolutely clean and sanitary. 
 
SPRING STUDIES 
 
 CHAPTER X 
 
 GARDEN STUDIES AND HOME PROJECTS 
 
 Getting ready for the garden. Gardening should 
 mean something more to you than merely planting, 
 cultivating and harvesting crops. Through it you 
 will be able to discover many scientific truths and 
 underlying principles concerning the life and habits 
 of plants, kinds of soil, principles of drainage and 
 the vitality of seeds. This means that special studies 
 and experiments must go along with your garden- 
 ing. Then, too, you must conduct your work accord- 
 ing to sound business principles if you wish to get 
 real value out of it. 
 
 One of the first things to do is to write to seed 
 firms for catalogues and send for your seeds. There 
 are a number of associations and seed houses that 
 make special prices to school children.* 
 
 Look over the garden projects suggested in this 
 chapter before you decide definitely what to plant. 
 
 *Two of these are: The Children's Flower Mission, Cleveland, 
 Ohio; The School Garden Association, Boston, Mass. 
 
 139 
 
140 STUDIES IN SCIENCE 
 
 You should be influenced in your decision by the 
 disposal you expect to make of your garden products. 
 If you are planning to use your vegetables upon the 
 home table, you should consult with the family to 
 find out what they prefer. If you expect to market 
 your produce, you should find out from grocerymen 
 or truck gardeners what vegetables are likely to be 
 in greatest demand. 
 
 It is worth while also, if you have a good sized 
 plot, to give a small space to new or unusual vege- 
 tables. There are a number of palatable and nutri- 
 trious vegetables that many people do not grow or 
 use because they know nothing about them. You 
 may succeed in introducing some of these into your 
 home and neighborhood. If you have a small plot on 
 the school grounds it may be used as an experimental 
 garden in which new varieties of vegetables may be 
 grown and tested. The small school plot may also 
 be used to demonstrate some of the principles of 
 gardening, as well as to raise material for special 
 study. 
 
 Tools. If you are starting a garden for the first 
 time, you will have to purchase tools with which to 
 work, unless your parents have all that are neces- 
 sary. If they garden on a large scale, they prob- 
 ably use some implements such as plows, harrows 
 and cultivators drawn by horses. If you have a small 
 
GARDEN STUDIES AND HOME PROJECTS 141 
 
 garden of your own, you will need the following hand 
 tools: 
 
 1. For preparing the seed-bed: a spade, spading 
 fork, rake. 
 
 2. For planting: a line, or measuring stick, hoe. 
 
 3. For cultivating: hoe, hand weeder, wheel hoe. 
 
 4. For raising plants indoors : shallow boxes, called 
 flats. 
 
 5. For transplanting: a trowel, dibber, watering 
 can. 
 
 Making a hotbed. A hotbed is an inexpensive and 
 convenient place in which to raise plants that must 
 be started very early in the season and transplanted 
 afterwards. 
 
 The parts of a hotbed are: 1. The pit in which 
 material is placed to furnish artificial heat. 2, The 
 frame. 3. The sash. 
 
 The pit should be of such size that the sash will 
 just cover it; an ordinary hotbed sash is six feet long 
 and three feet wide. A small hotbed then, may be 
 made 3x6 ft., 6x6 ft., 3x12 ft., according to the num- 
 ber of sashes. If you have an old window sash about 
 the place, the pit may be made to fit this sash. 
 
 Dig the pit about two feet deep in a well drained 
 spot. Place posts in the corners and nail planks to 
 these. This makes the frame. The posts should 
 extend twelve inches above the ground on the north 
 
142 
 
 STUDIES IN SCIENCE 
 
 m$w 
 
 CM 
 
 feb 
 
GARDEN STUDIES AND HOME PROJECTS 143 
 
 side and eight inches on the south, thus making your 
 bed slope toward the south. 
 
 When the pit with the frame is ready, procure some 
 fermenting stable manure, which is from one-third to 
 one-half straw or litter used for bedding. Several 
 days before making the hotbed the manure should 
 be placed in a pile four or five feet high so that fer- 
 mentation will begin. It should be turned over with 
 a fork so that it will ferment evenly in all parts. 
 Place a layer of this in the bottom of the pit and 
 tramp or pound it down. Continue putting in layers 
 and tramping them until the manure is from fourteen 
 to fifteen inches deep. On top of this place a layer 
 of good soil about four inches in depth. 
 
 If the bed is more than three feet long, place sup- 
 ports for the sashes every three feet. If it is very 
 cold weather, a double sash should be used. A layer 
 of manure piled around the frame on the outside will 
 be of service in conserving the heat. 
 
 Planting. The hotbed is now ready for use unless 
 the temperature is too high. Heat is produced by 
 chemical changes that are taking place in the decay- 
 ing manure. Place a thermometer in the soil and wait 
 for the right temperature. A few plants like egg 
 plants, peppers, or tomatoes may be planted when 
 the temperature is between 85 and 90 F. For most 
 seeds a temperature between 70 and 80 F. is safest. 
 
144 STUDIES IN SCIENCE 
 
 Plant your seeds in rows, extending north and south. 
 You may put the rows quite close together, from four 
 to six inches. The soil should be slightly moist when 
 you plant the seeds. Firm the soil over the seeds 
 just as you would if you were planting them out-of- 
 doors in the garden. 
 
 Care of the hotbed. Three conditions are essential 
 in having your plants grow successfully in a hotbed: 
 
 1. The temperature must be kept as even as pos- 
 sible. 
 
 2. The soil must be kept moist. 
 
 3. The plants must receive a supply of fresh air. 
 Watering should be done in the morning rather 
 
 than in the evening. On bright warm days the sash 
 should be lifted a little, from one to three inches, in 
 order to admit fresh air and allow impure air to 
 escape. It may be left open tw T o or three hours in 
 the middle of the day. If the weather turns sud- 
 denly cold, an extra covering of boards, pieces of old 
 carpets or canvas should be thrown over the hotbed 
 at night. 
 
 A hotbed in connection with a school garden may 
 furnish enough plants for all the children to set out 
 in their home or individual gardens. 
 
 Hotbeds are sometimes used to raise certain plants 
 as lettuce, radishes and spinach for table use during 
 cold weather. Sometimes steam or hot water pipes 
 
GARDEN STUDIES AND HOME PROJECTS 145 
 
 are used instead of manure to produce the needed 
 heat. 
 
 Cold frames. A cold frame is another device for 
 raising plants that are to be transplanted. It is sim- 
 ilar to the hotbed except that it does not have the 
 manure to produce artificial heat. It consists, then, 
 of the frame and the sash. A frame may be made 
 so that it may be moved from one place to another. 
 
 Fig. 28. A cold frame. 
 
 The frame should be twelve inches high on one side 
 and eight inches on the other, just as the frame of 
 the hotbed. It should also be the proper length and 
 width to fit the sashes. It may be placed in a well 
 drained spot in the garden. The soil should be dug 
 and thoroughly pulverized before the frame is put 
 into place. A layer of manure around the outside 
 will help to keep the temperature even. 
 
146 STUDIES IN SCIENCE 
 
 A cold frame may be used to start certain plants 
 that later may be transplanted to the garden. Cab- 
 bage, cauliflower, tomato plants, brussels sprouts, 
 and kohl-rabi may be grown successfully in a cold 
 frame, planting them the latter part of March or the 
 first of April. Some flowering plants from which 
 you wish to get early results as cosmos, gaillardia, 
 sweet scabious and salvia, may be started in the cold 
 frame and then transplanted to the garden. 
 
 The care of plants in the cold frame is similar to 
 that employed in the use of the hotbed. 
 
 Cold frames are frequently used to harden plants 
 that have been grown in hotbeds before setting them 
 out in the garden. 
 
 Do you know why the temperature of the cold frame 
 is warmer than the outside air! The answer involves 
 a principle of physics. The heat rays of the sun 
 pass through the transparent glass and heat the soil 
 in the cold frame. The heat that radiates from the 
 soil cannot pass out through the glass, so you see it 
 must accumulate inside the frame. 
 
 Preparing the seed-bed. To insure a successful gar- 
 den you must see that the soil is in good condition 
 before you plant your seeds or set out your plants. 
 
 Plow or spade it to a depth of from 10 to 12 inches. 
 A spading fork will give better results than a spade. 
 Then pulverize it with a harrow or rake till it is fine 
 
GARDEN STUDIES AND HOME PROJECTS 147 
 
 and mellow. If it is a clay soil be careful not to work 
 it when it is very wet. If when you take up a hand- 
 ful and squeeze it the particles stick together and 
 will not fall apart when you drop the lump, it is too 
 wet. If the particles fall apart the soil is in good 
 condition so far as moisture is concerned. 
 
 In order to have a successful garden it must be 
 well drained, must be rich in organic matter or humus, 
 and contain in available form all the soil elements 
 that plants need for their growth. In order to keep 
 the soil in excellent condition, with a constant supply 
 of moisture, you must cultivate your garden fre- 
 quently. Never allow a crust to form and remain. 
 This means cultivating after every rain. 
 
 BOYS AND GIRLS CLUBS 
 
 While any of the projects suggested in this and other chapters 
 may be undertaken individually in your home, it will add both 
 interest and profit to the work if a number of boys and girls of 
 the community meet and organize a club. Here various kinds of 
 work may be discussed and you can decide what particular projects 
 you wish to undertake as a club. The value of the club is that it 
 affords an opportunity to learn much from each other about the 
 work. You will be more interested in the work itself when you 
 know what others are accomplishing. Then, too, it affords an ex- 
 cellent opportunity to receive some training in conducting public 
 meetings, in parliamentary practice, and in speaking before the 
 public. 
 
 Many state universities have in cooperation with the U. S. De- 
 partment of Agriculture and the Bureau of Education a club leader 
 who gives his entire time to the work of helping boys and girls to 
 form clubs and to carry on projects in connection with them. If 
 
148 STUDIES IN SCIENCE 
 
 you wish to organize a club the first thing you should do is to apply 
 to the club leader of your state for information. He will send you 
 bulletins and other material explaining exactly how to proceed. 
 
 PROJECT ONE 
 
 TOMATOES 
 
 Material. Seeds and seed catalogues ; flats or boxes. 
 
 If you are planning to raise tomatoes, you should 
 decide first of all whether you want to try more than 
 one variety. Looking in your seed catalogue you 
 find some listed as early varieties, other as late. 
 Usually the early tomatoes are smaller than the main 
 crop tomatoes. It is worth while to grow a few of 
 these for early market or home use; for canning the 
 larger varieties are better. 
 
 Planting. If you live in a. warm climate plant your 
 seeds out-of-doors; if in a cool climate, you must start 
 them in-doors. Can you explain why? It is because 
 the tomato is not hardy enough to plant out-of-doors 
 early in the spring in a cold climate. If you wait 
 until the ground is warm enough for the seeds, the 
 season will be too short for the fruit to ripen. 
 
 Place some good rich soil in a box. Use a flat 
 or a shallow box about two and one-half or three 
 inches deep. Scatter the seed broadcast over the 
 soil or sow in drills two inches apart. Cover with 
 about one-half inch of soil and firm the soil well. 
 
GARDEN STUDIES AND HOME PROJECTS 149 
 
 If you have a hotbed, place the flat in this; keep 
 well watered and ventilated. If you have no hot- 
 bed, the plants will do fairly well in a sunny window 
 in the school room, or in the kitchen. Care should be 
 taken not to allow them to chill on cold nights. 
 
 If the plants are not too crowded, they may be left 
 in the flats until time to transplant. You will get 
 better results, however, if when the plants are between 
 two and three inches high you transplant them to 
 small flower pots, old berry boxes, tin cans or into 
 other flats. If you use the cans, be sure to punch 
 holes in the bottom for drainage. Do not keep the 
 plants too warm, but allow them to grow rather 
 slowly in order to form a thick stocky stem. 
 
 Transplanting. When all danger of frost is past, 
 transplant to the garden. The small early varieties 
 may be placed two and one-half or three feet apart; 
 the large ones from three to four feet. 
 
 Care of plants. As you know, the tomato plant has 
 a weak stem which if left to itself will spread over 
 the ground. To get best results you should make a 
 support of some sort. Soft twine or strips of cloth 
 should be used to tie the plants to the support. 
 
 It is not well to allow all the buds that appear to 
 develop. If you look closely at your plants when 
 they are four or five inches high you find new buds 
 appearing in the axils of the leaves. Most of these 
 
150 STUDIES IN SCIENCE 
 
 should be pinched out. This compels the plant to 
 grow tall. When your plant has a number of fruit 
 clusters on it, you may prevent its growing taller 
 by pinching out the top bud. You should cultivate 
 frequently enough to keep a soil mulch. 
 
 Experiments, (a) Test two or three varieties to 
 determine which gives best results, (b) Train sev- 
 eral plants on supports. Leave the same number 
 untrained. Keep a record of results. 
 
 Harvesting and canning. If you are marketing 
 your crop, be careful not to bruise the fruit. Put 
 together the tomatoes that are similar in size, shape 
 and color. You will get a better price for choice fruit 
 if you grade it carefully. 
 
 Seventh and eighth grade girls can successfully 
 can tomatoes. Select firm, thoroughly ripe fruit. 
 The skins are removed by placing the tomatoes for 
 a few seconds in water heated to the boiling point. 
 Eemove, dip immediately into cold water, and the 
 skins will slip off easily. 
 
 There are two methods of canning that you may 
 use. The old-fashioned plan is to cook the tomatoes, 
 then place them in cans and seal. First the cans, tops 
 and rubbers should be sterilized by immersing in 
 boiling water. 
 
 The newer and better plan is the cold pack or hot 
 water-bath method, using the closed boiler or the 
 
GARDEN STUDIES AND HOME PROJECTS 151 
 
 home canning outfits. Both of these methods with 
 much useful information are described and explained 
 in Farmers' Bulletin No. 521, "Canning Tomatoes at 
 Home and in Club Work." This may be obtained 
 free by sending to the IT. S. Department of Agricul- 
 ture, Washington, D. C. 
 
 It will be quite worth while for a school to have 
 in connection with the Domestic Science department 
 a canning demonstration with a wash boiler or deep 
 kettle and a canning outfit. 
 
 You may use your tomatoes also for pickles, chow- 
 chow, piccalilli and sweet preserves. You will find 
 recipes for these in the bulletin named above. 
 
 Record of Tomato Project. 
 
 1. Name of variety. 
 
 a. Date of planting. 
 
 b. Date of transplanting. 
 
 c. Date when ready for use. 
 
 2. Expenditures. 
 
 a. Cost of seeds. 
 
 b. Rental value of plot size of plot. 
 
 c. Labor Estimate hours of work. 
 
 d. Cost of fertilizer. 
 
 e. Total expenditure. 
 
 3. Receipts. 
 
 a. Yield in pounds or bushels. 
 
 b. Amount sold value. 
 
 c. Amount used or canned value. 
 
 d. Total receipts. 
 
 e. Net profits. 
 
 4. Note any points that will be of value for future reference. 
 
152 STUDIES IN SCIENCE 
 
 PROJECT TWO 
 
 EOOT CROPS 
 
 Material. Roots of beets, turnips, parsnip, carrot, 
 and salsify; seeds of each. 
 
 Root crops is a name given by market gardeners to 
 plants whose roots are used for food. Make a list of 
 all the root crops that you know. Choose any one 
 of them for observation and study. The study may 
 be made late in the fall or any time during the winter 
 or early spring. 
 
 Seed-bed and seeds. Work the soil thoroughly so 
 that it will be loose and deep. It should also be well 
 drained. 
 
 The seeds of most root crops do not retain their 
 vitality more than two years. It is safer to use one- 
 year-old seeds. 
 
 If you are not sure that the seeds are fresh, test 
 them to see if they will germinate. Place a few in 
 moist sand or soil. Keep moist but not too warm 
 and watch to see whether they will germinate and 
 grow. The seeds are slow to germinate, taking from 
 ten days to three weeks, so do not be discouraged 
 when the plants do not appear within a few days. 
 You should make the test during the latter part of 
 winter or early spring. 
 
 Planting. Time: All the root crops are cool weather 
 
GARDEN STUDIES AND HOME PROJECTS 153 
 
 plants and may be planted as early as the ground 
 can be worked in the spring. Beets, carrots, and 
 turnips may be planted at intervals during the sum- 
 mer for a succession of crops. 
 
 Distance apart of rows: Beets, carrots, parsnips, 
 salsify, turnips, 12 inches. 
 
 Depth : All the above except turnips, 1 inch. Tur- 
 nips l /2 inch. 
 
 It is very essential to firm the soil well. If the 
 seeds germinate they must be kept moist. Firming 
 the soil brings it in close contact with the seeds, so 
 that the moisture is kept constant by capillary action 
 of the soil. 
 
 Some gardeners plant small, quick germinating 
 seeds, as radishes or lettuce, in the rows with parsnips 
 and carrots. These help to break the crust for the 
 slower plants and at the same time mark the rows so 
 that the soil can be cultivated without the possibility 
 of injuring the young seedlings that may be just ready 
 to break through. 
 
 Thinning 1 . It is a good plan, in order to secure a 
 good stand, to plant the seeds rather close, about an 
 inch apart. If all grow, thin to a distance of from 
 3 to 4 inches. 
 
 Harvesting. Beets will be ready to use in from 
 8 to 10 weeks after planting. They are much better 
 when young than if allowed to reach their full growth. 
 
154 STUDIES IN SCIENCE 
 
 They may be canned successfully by the closed boiler 
 or steam method. 
 
 Carrots are ready for use in from 12 to 15 weeks. 
 They too are better young. They may also be canned. 
 Both beets and carrots bring a better price at this 
 time than later. Turnips are ready in from 8 to 12 
 weeks. Parsnips and salsify may be left in the 
 ground and used during the winter. While some 
 people think that frost improves them, they are all 
 right to use in the early fall. 
 
 Any of the root crops may be kept fresh and crisp 
 for use all winter by placing them in boxes of moist 
 soil, sand or leaves, and keeping them in a cold cellar. 
 A temperature just above freezing is best. They may 
 also be kept in pits out-of-doors. To preserve them 
 in this way they should be placed in a conical pile, 
 covered with six or eight inches of straw, then with 
 a layer of earth. In very cold regions a layer of 
 manure may be put on top of the soil. 
 
 Experiment, (a) If you have an experimental plot, 
 set out some roots of beets, carrots, etc., and raise 
 some seeds of your own. 
 
 (b) Try different varieties of any of the root crops 
 suggested to determine which give best results in your 
 garden. 
 
 Keep a record of your crop similar to the one sug- 
 gested for tomatoes. 
 
GARDEN STUDIES AND HOME PROJECTS 155 
 
 PROJECT THREE 
 
 POTATOES 
 
 Material. A number of potatoes, a small bottle of 
 tincture of iodine, some red ink. 
 
 Study. Examine a potato. What do you find scat- 
 tered over the surface? Where are the eyes most 
 numerous ? Where are the smallest ones ; the largest ? 
 What are the eyes? Do any of them show signs of 
 growth! What else do you find on the potato! 
 
 The eyes are buds, and the end of the potato on 
 which the eyes are so numerous is called the bud or 
 seed end. Opposite this is the stem end. 
 
 What is the potato? To answer this, hold a potato 
 with the bud end upward. Now suppose you could 
 stretch it out many times its length and have the 
 thickness reduced accordingly. What part of a plant 
 would it resemble! 
 
 Cut a potato in two through one of the eyes. How 
 many different structures has it! 
 
 Experiment. What is the potato made of? 
 
 1. Weigh a potato after first removing the peel- 
 ing. Put it in a warm place. What happens? After 
 a few days weight it again. How much has it lost? 
 What causes the loss? 
 
 2. Scrape the white portion from two or three 
 potatoes. Put the scrapings into a glass of water. 
 
156 STUDIES IN SCIENCE 
 
 Stir thoroughly. Allow the glass to stand for twen- 
 ty-four hours. What do you find in the bottom? 
 Carefully pour off the scraps and water leaving noth- 
 ing but the white layer in the bottom. Pour a small 
 amount of boiling water over this. What happens! 
 Put a few drops of iodine on the starch and note 
 effect. 
 
 Experiment. Of what use is the starch to the 
 potato? Fill a box or large flower pot nearly full 
 of soil. Plant two small sized potatoes. Cover about 
 two and a half inches deep. Keep watered. When 
 the plants are about three inches high dig up one and 
 examine the potato noting any changes that have 
 taken place. Leave the other for a number of weeks, 
 then examine it. The same experiment may be tried 
 to better advantage out-of-doors in the garden. 
 
 Experiment. Cut a slice from the stem end of a 
 potato tuber. Set the cut end of the tuber in a dish 
 with about a quarter of an inch of red ink in the bot- 
 tom. Allow it to stand several hours. Now make 
 a number of thin slices. What has taken place? 
 
 Discussion. The fact that the potato has buds tells 
 you that it is a stem. Since it grows in the ground 
 it is an underground stem. There are several differ- 
 ent kinds of underground stems. This kind is called 
 a tuber. In propagating potatoes then we use tubers 
 instead of seeds. 
 
GARDEN STUDIES AND HOME PROJECTS 157 
 
 The tuber is made up chiefly of water and starch. 
 The blue color that appeared when you used the 
 iodine indicated the presence of starch. The potato 
 also contains a few minerals. Its structure is like 
 that of any stem. The outside layer we call the peel- 
 ing. The dark line is the woody tissue. The part 
 between the wood and peeling is the cortex. The 
 dark central part, with the rays extending from it, 
 is the pith. The white part is called the medulla. 
 Your experiment shows that the woody tissue carries 
 water and other food materials to the tuber. 
 
 Pla.nting. Time: Early potatoes may be planted 
 as soon as the ground is dry enough to cultivate in 
 the spring. Late varieties may be planted in May 
 or June. The northern states that raise quantities 
 of potatoes usually plant them about the middle of 
 May. 
 
 The seed-bed: Potatoes need a deep, rich, mellow 
 seed-bed. To insure this the soil should be plowed 
 deeply and then disked or harrowed a number of 
 times. A soil that has had clover or alfalfa growing 
 on it the year before is excellent for potatoes. 
 
 Cutting the tubers: Many experiments have been 
 made at agricultural stations to determine the most 
 economical way to cut the tubers for planting. A 
 chunky, compact piece with at least two eyes usually 
 gives best results. 
 
158 STUDIES IN SCIENCE 
 
 Space between rows: In Jhe garden, wliere hand 
 cultivation is practiced the rows may "be 2% feet 
 apart. When the horse cultivator is to be used they 
 should be 3 feet apart. 
 
 Space between hills: 12 to 15 inches. Plant one 
 piece in each hill. 
 
 Depth: In heavy, compact soil 3 inches. In loose, 
 mellow soil 4 to 5 inches. 
 
 Cultivation and care. Work the soil frequently; 
 harrow the ground at least once before the plants 
 are up. All through the growing season cultivate 
 often enough to keep the soil fine and loose. Care 
 should be taken not to cultivate too deeply lest the 
 roots be injured. 
 
 Enemies. If you find traces of the fungous disease 
 called scab on your seed potatoes you can prevent its 
 attacking your new potatoes by treating the seed 
 with a solution of formaldehyde. Use one ounce to 
 two gallons of water. Leave the potatoes in the solu- 
 tion from one and a half to two hours. 
 
 The Colorado potato beetle is likely to be your 
 worst foe. For treatment, spray with arsenate of 
 lead or Paris green. 
 
 For potato blight spray with Bordeaux mixture 
 or lime-sulphur mixture. The latter will also kill 
 aphids or plant lice. 
 
 Harvesting, marketing and storing. Early, potar 
 
GARDEN STUDIES AND HOME PROJECTS 159 
 
 toes may be dug for market when they are large 
 enough to use before they are fully matured. If you 
 are planning to sell your crop you may get a better 
 price for it at this time than if you wait until later. 
 
 You will probably harvest your main crop when 
 the potatoes are mature. This means when the vines 
 are dead. If you store them for future use or plan 
 to sell them later you should keep them in a cool, 
 dark place at a temperature from 33 to 35 F. They 
 may be stored in a cool cellar or in an outdoor pit. 
 
 Selecting seed potatoes. When digging your pota- 
 toes watch for hills that give the best yield; that is, 
 the greatest number of large, well formed potatoes. 
 Save these for seed next year. If you do not get 
 enough choice ones to plant your entire plot, use 
 these to plant a small plot and from this again choose 
 the best hills. In the course of three or four years, 
 by this simple plan of selection you may produce a 
 seed potato that will be worth many times the price 
 of ordinary potatoes. 
 
 Keep a record of your project similar to that sug- 
 gested for tomatoes. 
 
 Experiments. There are a number of interesting 
 experiments that you may make either at home or 
 in the school garden. 
 
 1. Does careful selection of seed potatoes pay? 
 Plant two plots of equal size, one with tubers care- 
 
160 STUDIES IN SCIENCE 
 
 fully selected as suggested above, the other with tub- 
 ers taken at haphazard from the bin. Give both the 
 same cultivation. Compare weights when the crops 
 are harvested. 
 
 2. Is it worth while to treat potatoes for scab! 
 Plant two plots of equal size with the same kind of 
 potatoes. Treat the tubers of one with formalin; 
 plant the other w r ith untreated potatoes. Compare 
 as to yield and quality of potatoes. 
 
 3. What is the effect of frequent cultivation? 
 Plant two plots of equal size with the same kind of 
 potatoes. Cultivate one twice as frequently as the 
 other. Compare yields. Keep a record of the extra 
 time and labor expended so you may take that into 
 consideration when you check up results. 
 
 4. Test two or three varieties of potatoes as to 
 yield and quality. Plant plots of equal size and give 
 similar culture. Some of the common early varieties 
 are Early Chios, Early Eose, Irish Cobbler and Early 
 Puritan. The leading late varieties are Rural New 
 Yorker, Seneca Beauty, Burbank and Green Mountain. 
 
 PROJECT FOUR 
 
 ONIONS 
 
 Material. Some large onions, several onion sets, 
 
 seeds, and if possible a stem with top sets or bulblets. 
 
 Study. An onion is a bulb. Examine one care- 
 
GARDEN STUDIES AND HOME PROJECTS 161 
 
 fully. What do you find at the lower end? At 
 the upper end? Describe the covering. Cut one bulb 
 crosswise and another lengthwise. Of what is the 
 bulb composed? Where are the thickest layers? 
 What is the color of the central portions? Look 
 closely at the place where the layers are fastened. 
 What is their relation to the hard flat plate that you 
 found on the outside of the bulb? How is the cen- 
 tral shoot related to this? What is this plate? 
 
 Experiment. Wliat is the value to the onion of 
 the thick, juicy layers? 
 
 Place a medium sized onion in the mouth of a large 
 bottle full of water. The lower part of the bulb 
 should rest in the water. Watch its growth for a 
 number of weeks. Describe the roots and the leaves. 
 Explain the change that takes place in the bulb. 
 
 Compare sets with large onions, noting differences 
 and resemblances. How are the sets obtained? If 
 you have some top onions or bulblets, compare those 
 with the sets. 
 
 Examine the seeds. Note size, color and shape. 
 How can you obtain onion flowers and seeds? 
 
 Discussion. The onion bulb is really composed of 
 thick, juicy, modified leaves that contain a large 
 amount of food. The flat plate-like portion to which 
 they are fastened is the true stem of the bulb. You 
 find from your experiment that the bulb sends out 
 
162 STUDIES IN SCIENCE 
 
 the fibrous roots below and the green shoot above. 
 If you examine the latter after a number of weeks, 
 you find that most of the food in it has been used up 
 and it has become very soft and flabby. 
 
 Sets and seeds. Sets are small bulbs that have 
 been grown from seeds the year before. In some 
 places the seeds are planted late in the season and in 
 the fall the small bulbs are taken up and stored over 
 winter. Most growers of sets, however, plant the 
 seeds very thick early in the spring. The plants are 
 so crowded that the bulbs cannot grow large. When 
 the tops begin to die the small bulbs are taken up, 
 dried and stored. Top sets or bulblets are produced 
 by certain kinds of onions. They may be used to 
 produce new onions just as the true sets are used. 
 
 Onions are biennials, so if you wish to raise seeds 
 you must set out the large bulbs which send up a 
 flowering stem. Sometimes the large sets will do 
 the same thing. If they send up seed stalks they 
 become tough and strong and are worthless. Sets 
 from % to % of an inch in diameter are the best 
 size to use if you wish to raise ripe onions. The 
 larger sets may be used for green or bunch onions. 
 
 Planting. There are several different methods 
 which you may use to raise an onion crop. If you 
 wish an early crop, use sets. You may also use bulb- 
 lets or you may procure the potato onion or multi- 
 
GARDEN STUDIES AND HOME PROJECTS 163 
 
 plier. This produces numerous bulbs growing around 
 the bulb you set out. For an early crop you may set 
 out multiplier onions in the fall. In a cold climate 
 cover them lightly with leaves or straw. They will 
 be ready for use very early in the spring. For the 
 general crop plant seeds. Onions are hardy, cool 
 weather plants, and it is quite essential to plant them 
 very early so they may get a good start before hot 
 weather. 
 
 Distance between rows, 12 to 16 inches. 
 
 Distance between sets in the row, 3 inches. 
 
 Sow seeds thick and later thin to same distances 
 as sets. 
 
 Depth of seeds, % to 1 inch. 
 
 Depth of sets, place so the shoot will just come 
 above the surface of the soil. 
 
 Firm the soil well over both sets and seeds. 
 
 Care of plants. Keep well weeded and cultivated. 
 The hand and the hand weeder are the best tools to 
 use at first with the seedling onions. After they are 
 three or four inches high the wheel hoe or cultivator 
 may be used. 
 
 Harvesting, marketing and storing. Onions raised 
 from sets will be ready for use in from four to six 
 weeks. Seed onions will be ready in from ten to 
 twenty-five weeks. 
 
 If you live near a market where green or " bunch 
 
164 STUDIES IN SCIENCE 
 
 onions" are in demand, it may pay you to market 
 some of your onions just as soon as they are large 
 enough to eat. Clean them carefully, trim off the 
 fibrous roots and tie them in bunches of ten or twelve. 
 
 If you wish to wait until the onions are ripe, keep 
 watch of the tops. As soon as they have fallen over 
 and turned yellow you may be sure that your onions 
 are in good condition to harvest. Pull them and twist 
 off the tops. Some gardeners leave them lying in 
 the rows in the garden to cure, but the method now 
 employed by the best market gardeners is to place 
 them in a dry, well ventilated place in the shade 
 rather than in the sun. A shed or corn crib will serve 
 the purpose. Spread them out so that the air may 
 circulate well among them. Do not allow them to 
 freeze. When cold weather approaches either sell 
 them or put them in a place where the temperature 
 remains above the freezing point. 
 
 Keep a record of your project similar to the one 
 suggested for tomatoes. 
 
 Onions require considerable care and labor, but 
 if you succeed in raising a good crop you will find 
 them very profitable. 
 
 Experiments, a. Plant equal areas with sets and 
 seeds. Keep separate records to determine which is 
 more profitable. 
 
 b. Plant equal areas of different varieties of onions, 
 
GARDEN STUDIES AND HOME PROJECTS 165 
 
 red, white, or yellow. Keep careful records to deter- 
 mine which gives best results. 
 
 PROJECT FIVE 
 
 CUCUMBERS AND OTHER CUCURBITS 
 
 Material. Seeds of squash, pumpkin, and cucum- 
 bers; small flats or boxes, soil or sand; seed cata- 
 logues. 
 
 If you are planning to raise cucumbers or any of 
 their relatives, consult your seed catalog to decide 
 what varieties you wish to grow. Some cucumbers 
 are better adapted for slicing than others, while some 
 are especially good for pickling. Some varieties of 
 squashes and pumpkins are ready for use in the sum- 
 mer; other are not ripe until fall. 
 
 Seeds and seedlings. Soak some seeds twenty-four 
 hours; squash or pumpkin seeds are best for this 
 study because of their large size. Examine a seed 
 and determine the point where it was attached to 
 the inside of the fruit. Remove the covering and 
 describe what you find on the inside. Consult Fig. 28 
 to get the names. 
 
 Experiment. What part of the plant will each part 
 of the seed produce? To answer this question plant 
 three or four seeds each of squash, pumpkin and 
 cucumber in a box of sand or other light soil. Keep 
 in a warm temperature and water frequently enough 
 
166 STUDIES IN SCIENCE 
 
 to keep the soil moist. Record the date of planting. 
 When the plants are up solve the following problems: 
 
 How long does it take each to appear above the 
 ground? What part of the plant appears first? Do 
 the seed coats come up? What changes take place 
 in the cotyledons? Dig up one of the plants to deter- 
 mine what part of the seed produces the root. How 
 do the first pair of leaves, the cotyledons, differ from 
 the other leaves of the plant? (You may have to 
 wait some weeks to answer this question.) What 
 finally becomes of the cotyledons? Compare the seed- 
 lings with each other for likenesses and differences. 
 
 Discussion. No doubt you can see a strong family 
 resemblance among the seeds and seedlings. The 
 entire family are natives of warm regions. 
 
 The cotyledons which produce the first leaves have 
 some food stored in them which starts the growth 
 of the seedling. Then they begin the work of manu- 
 facturing food for the plant and continue to do this 
 till other leaves are produced, when they wither and 
 drop off. 
 
 Planting. Time: Cucumbers and their kin are 
 warm weather plants so must not be planted until all 
 danger of frost is past and the soil is warm. The 
 soil should be well pulverized and very rich. It is 
 sometimes a good plan to spade a fertilizer into it 
 two or three weeks before planting time. 
 
GARDEN STUDIES AND HOME PROJECTS 167 
 
 There are two methods of planting : 1. The mound 
 hill, which is raised six to nine inches above the level 
 of the garden. 2. The hill on a level with the garden 
 soil. Whichever plan you use put ten to twelve seeds 
 into each hill. This provides for the destruction of 
 some of the plants by insects and yet probably leaves 
 enough to insure a crop. 
 
 Distance apart of hills : Depth : 
 
 Cucumbers, 4 to 5 feet 1 to 1% inches 
 
 Muskmelons, 5 to 6 feet 1 to l l / 2 inches 
 
 Watermelons, 8 to 12 feet l 1 ^ inches 
 
 Squashes and pumpkins, 8 to 12 feet 2 inches 
 
 Cucumbers may be started indoors six or eight 
 weeks before they could be planted outside. Plant 
 three or four seeds in good soil in an old berry box. 
 Or cut a piece of grass sod about three inches thick 
 and from four to five inches square, turn it upside 
 down and plant the seeds in the fine soil. Keep in 
 a hotbed or green house until danger of frost is past. 
 
 Care of plants. If all the seeds in the outdoor 
 plantings germinate, allow the seedlings to grow for 
 a while; then if none are destroyed by insects, pull 
 the weakest plants leaving three or four of the strong- 
 est ones. Cultivate frequently till the plants have 
 developed thrifty vines. To know how to treat insect 
 and fungous enemies of your cucurbits see page 222. 
 
 Harvesting. If you are to use your cucumbers on 
 
168 STUDIES IN SCIENCE 
 
 the home table, gather them when the right size to 
 slice and keep in a cool place. Placing them in a 
 refrigerator a couple of hours before peeling will 
 improve their crispness. It is a mistake to allow 
 them to stand several hours in salt water. This 
 results in toughness. Cucumbers to slice are usually 
 in demand on the market. Gather them every day 
 or two, and use the same care to keep them fresh as 
 you w-ould for your own table. 
 
 If you are raising cucumbers for pickles, gather 
 them at least every two days. Grade them, placing 
 all of about the same size together. These may be 
 pickled at home, or if you live near a pickle factory 
 you will probably find a good market for them. 
 
 Record. Keep a record similar to the one sug- 
 gested for tomatoes. Estimate their value by the 
 dozen instead of by the pound. 
 
 Experiment. 1. Try two or three varieties keeping 
 separate accounts to see which is most profitable, 
 
 2. Plant an equal number of mound and level hills 
 and determine which gives the better results. 
 
 PROJECT six 
 
 BEANS AND PEAS 
 
 Material. Two or three different kinds of beans; 
 box of soil or sand; seed catalogues. 
 
GARDEN STUDIES AND HOME PROJECTS 
 
 169 
 
 Study. Soak some beans of any variety over night. 
 Compare a soaked specimen with a dry one and note 
 changes that have taken place. How many distinct 
 parts do you find in the bean? 
 
 What will each part produce when the bean ger- 
 minates and grows! To an- 
 swer this question plant a 
 number of seeds in a small box 
 containing soil. Put in a warm 
 place, the temperature of the 
 room is all right, and keep 
 moist. Watch for the appear- 
 ance of the plants. How do 
 they break through the soil? 
 .Dig up one seed just as soon as 
 
 the cotyledons are out of the Fig 29 Bean geed and 
 ground. Describe the root as ^ ed jfg- A One cotyledon; 
 
 B, Hypocotyl and radicle; 
 
 to color, length and beginnings C ' The cotyledons spread 
 
 open; D, A small part ot 
 
 of branches. What part of hypocotyl; E, Plumule; F, 
 
 Cotyledons on growing seed- 
 
 the Seed produced the root? ling; G, Plumule developed 
 
 ,.,,,, into first pair of leaves; H, 
 
 Keep the plants till they Root developed from the tip 
 ., . , , . , of the hypocotyl, the radicle. 
 
 are two or three inches high 
 
 and note all the changes that take place. What 
 finally becomes of the cotyledons? What value are 
 they to the plant? What produces the first true 
 leaves? When do the next leaves appear? Dig- 
 up another plant to discover any additional facts 
 
170 STUDIES IN SCIENCE 
 
 concerning the roots. Look in your seed catalogues 
 for the classes of beans that are listed. Determine 
 how each kind is supposed to be used. 
 
 Discussion. You found your bean seed made up 
 of three distinct parts besides the cover or seed coat. 
 The thick cotyledons contain food for the growth of 
 the little plant. You noticed that they changed in 
 form and color; that is, they really grew a little them- 
 selves, but after most of the food in them was used 
 they dropped off. They are sometimes called seed- 
 leaves. The lower end of the hypocotyl produced the 
 root; the upper part produced part of the stem. 
 
 How long beans have been used as food no one 
 knows, but you will be interested to learn that most 
 of the species of beans that we grow are natives of 
 America. 
 
 Seed men usually classify their beans into string 
 or pod beans, shell beans, and dry beans. 
 
 Of the string beans the entire fruit or pod with the 
 seeds is eaten. Shell beans are removed from the pod 
 and eaten while immature. Dry beans are ripened 
 seeds that may be kept for months or even years. 
 
 Decide first what kind of beans you wish to grow. 
 If you wish them for market or table use early in 
 the summer, choose string varieties; if for market 
 or use in the late summer or fall, choose some variety 
 of shell bean. Nothing gives quite as good results at 
 
GARDEN STUDIES AND HOME PROJECTS 171 
 
 this time as lima beans. Some of the shell beans 
 may be allowed to mature and may then be used as 
 dry beans. The navy beans are the best and most 
 productive of the dry bean group. 
 
 Planting, Wait until all danger of frost is past 
 and the soil is warm. 
 
 Space between 
 Space between rows: . t . Depth: 
 
 Bush beans, either string or 
 
 dry, 2 feet. 3 to 4 inches. 1 to 2 inches ac- 
 
 cording to size. 
 
 Pole beans, 2'/o to 3 feet. 4 to 6 inches. 2 inches. 
 
 If you wish a succession of string beans, plant 
 some every two or three weeks. You may plan to use 
 the space in which you have grown early crops of let- 
 tuce or radishes for your late beans. 
 
 Harvesting, marketing and canning. String beans 
 are ready for use when the pod snaps easily. They 
 are sold by the pound or quart measure. Good yield- 
 ing varieties bring a good profit. The pole limas 
 yield better than bush varieties. They sell exceed- 
 ingly well when picked and shelled green. If you 
 have more than you can market in this way, let them 
 mature and sell them as dry beans. 
 
 All kinds of string and shell beans may be canned 
 by the cold pack or hot water bath method. When 
 the beans are cleaned and ready, dip into boiling 
 
172 STUDIES IN SCIENCE 
 
 water, allowing them to remain three minutes. Re- 
 move and put into cold water. Pack into jars, add 
 one level teaspoonful of salt to a quart and enough 
 hot water to fill the jar. Put on the rubber and par- 
 tially fasten the cover. Place the jars on the false 
 bottom of the boiler and pour in cold water till it 
 stands two inches above the jars. Allow them to boil 
 one and one-half hours. Remove from the boiler, 
 tighten the cover, and invert to cool. 
 
 Keep a record of your bean project. 
 
 Experiment. Test two or three different varieties 
 of string beans to determine which gives best results. 
 
 Canning. Besides the vegetables discussed in these 
 projects, many others that you grow may be preserved 
 for future use by canning. The purpose of boiling 
 before canning is to sterilize the vegetables so per- 
 fectly that no bacteria will be left to grow and mul- 
 tiply and thus cause souring and decay. Some vege- 
 tables, notably tomatoes, which contain considerable 
 acid, are very easily kept in cans. The reason for 
 this is that bacteria do not thrive well in an acid 
 medium. Most fruits contain some acid and are 
 more easily preserved by canning than vegetables. 
 In order to kill all the bacteria in vegetables which 
 do not have much acid, they must be subjected to 
 heat for a long period. In the home the most com- 
 mon method of canning is called the hot water bath. 
 
GARDEN STUDIES AND HOME PROJECTS 173 
 
 For this a large kettle or boiler may be used, a false 
 bottom may be made out of wood, two pieces of two 
 by fours with slats nailed across them. A wire rack 
 which may be purchased for ten or fifteen cents is 
 more satisfactory. Wire racks for individual jars 
 may be bought for ten cents apiece. The steps in 
 canning are as follows: 
 
 1. Can vegetables as soon as possible after taking 
 them from the garden. 
 
 2. Have vegetables and jars perfectly clean. 
 
 3. Blanch the vegetables. This means plunging 
 into boiling water for a definite period. A wire bas- 
 ket may be used, or they may be tied up in a square 
 of cheese cloth. This preserves the color, hardens 
 the tissues, and kills any baceteria that may be on 
 the outside. 
 
 4. Plunge into cold water leaving but a moment. 
 
 5. Pack into jars. Put a teaspoonful of salt into 
 each quart, then fill to the top with hot water. 
 
 6. Put on the rubber and the lid. Do not screw 
 the lid tight. 
 
 7. Put the jar into the heater in cold or slightly 
 warm water. Add water till the tops of the jars 
 are covered about two inches. 
 
 8. Boil the necessary number of minutes. 
 
 9. Remove from the water, tighten the covers and 
 invert to cool. 
 
174 
 
 STUDIES IN SCIENCE 
 
 The following is a time-table taken from the sup- 
 plement to Farmers' Bulletin, No. 521, Washington, 
 D. 0.: 
 
 TIME-TABLE 
 
 To be followed in the use of the four different types of portable 
 home canners. The hot water bath outfit is the wash boiler, lard tin 
 or pail with a false bottom. 
 
 Hot water Water seal Steam 
 
 Steam 
 
 Blanch 
 
 bath 
 
 outfit 
 
 pressure 
 
 pressure 
 
 
 or 
 
 outfit at 
 
 above 
 
 cooker 
 
 cooker 
 
 
 scald 
 
 212F. 
 
 212F. 
 
 5 Ib. 
 
 10 Ib. 
 
 Minutes 
 
 Minutes 
 
 Minutes 
 
 Minutes 
 
 Minutes 
 
 Apples (whole) 
 
 2 
 
 20 
 
 15 
 
 12 
 
 6 
 
 Apples (sliced) 
 
 2 
 
 15 
 
 13 
 
 10 
 
 6 
 
 Apricots 
 
 1-2 
 
 15 
 
 12 
 
 12 
 
 6 
 
 Asparagus 
 
 5-10 
 
 60 
 
 60 
 
 40 
 
 30 
 
 Beans, (lima and string) 
 
 5 
 
 90 
 
 60 
 
 60 
 
 30 
 
 Beets 
 
 G 
 
 90 
 
 75 
 
 60 
 
 40 
 
 Blackberries 
 
 
 12 
 
 10 
 
 6 
 
 3 
 
 Blueberries 
 
 
 10 
 
 8 
 
 6 
 
 3 
 
 Cherries 
 
 
 15 
 
 12 
 
 10 
 
 5 
 
 Corn (without acids).. 
 
 5-15 
 
 240 
 
 180 
 
 90 
 
 60 
 
 Grapes 
 
 
 15 
 
 15 
 
 10 
 
 6 
 
 Grape juice 
 
 
 15 
 
 15 
 
 10 
 
 5 
 
 Hominy 
 
 
 60 
 
 50 
 
 40 
 
 35 
 
 Huckleberries 
 
 
 10 
 
 8 
 
 6 
 
 3 
 
 Okra 
 
 5 
 
 60 
 
 60 
 
 40 
 
 30 
 
 Okra and tomatoes ..... 
 
 
 50 
 
 50 
 
 40 
 
 30 
 
 Oysters 
 
 
 50 
 
 50 
 
 40 
 
 30 
 
 Parsnips 
 
 
 90 
 
 60 
 
 40 
 
 30 
 
 Peas (garden and 
 
 
 
 
 
 
 English) 
 
 5 
 
 90 
 
 80 
 
 60 
 
 40 
 
 Pineapples 
 
 
 30 
 
 25 
 
 10 
 
 10 
 
 Peaches 
 
 1-2 
 
 15 
 
 12 
 
 10 
 
 5 
 
 Pears and plums 
 
 1-2 
 
 15 
 
 15 
 
 10 
 
 6 
 
 Pumpkins 
 
 5 
 
 60 
 
 60 
 
 45 
 
 35 
 
GARDEN STUDIES AND HOME PROJECTS 
 
 175 
 
 Hot water Water seal Steam Steam 
 
 Blanch bath 
 
 or outfit at 
 
 scald 212 F. 
 
 Minutes Minutes 
 
 Raspberries 15 
 
 Sauerkraut 50 
 
 Sausage 60 
 
 Sweet potatoes 5 90 
 
 Strawberries 15 
 
 Squash 5 60 
 
 Succotash 60 
 
 Tomatoes 1-2 22 
 
 Tomatoes and corn 80 
 
 Tomato juice 20 
 
 Turnips 6 90 
 
 Quince 2 30 
 
 Fish, pork 200 
 
 Chicken, beef 250 
 
 Figs 30 
 
 Spinach 5-10 60 
 
 Other greens 5-10 90 
 
 Rhubarb '. 1-3 15 
 
 Egg plant 5 60 
 
 Carrots 5 . 60 
 
 Cauliflower . .5 60 
 
 outfit pressure pressure 
 
 above cooker cooker 
 
 212F. 5 Ib. 10 Ib. 
 
 Minutes Minutes Minutes 
 
 12 
 
 50 
 60 
 75 
 12 
 60 
 
 20 
 70 
 20 
 75 
 25 
 200 
 240 
 20 
 60 
 90 
 15 
 50 
 60 
 60 
 
 8 
 
 40 
 
 40 
 
 60 
 
 8 
 
 45 
 40 
 10 
 60 
 15 
 60 
 15 
 120 
 180 
 10 
 40 
 60 
 10 
 45 
 45 
 40 
 
 5 
 
 25 
 35 
 40 
 
 5 
 
 35 
 30 
 
 6 
 
 40 
 10 
 40 
 10 
 60 
 40 
 
 5 
 
 30 
 40 
 
 5 
 
 30 
 30 
 30 
 
 Size of jar. When cooking products in pint or 
 half -pint jars, deduct 3 or 4 minutes from time given 
 above. When cooking in two-quart jars, add 3 or 4 
 minutes to time. The estimate given is for quart jars. 
 
CHAPTER XI 
 
 FARM CROPS AND HOME PROJECTS 
 
 If you live in the country you will probably want 
 to undertake some agricultural projects as well as 
 to raise vegetables or flowers. Any farm crop that 
 can be grown in your community will make a project 
 worth while. You will want to find out something 
 about the habits of the plants you decide to grow, for 
 your projects should help you to discover for your- 
 self some of the truths and underlying principles of 
 life as well as teach you how to grow crops for profit. 
 
 PROJECT SEVEN 
 
 CORN 
 
 Material. Grains or corn, flats, plates, and muslin 
 for germination tests. 
 
 The kernel. Put a number of corn kernels into 
 slightly warm water and let them soak over night. 
 Examine a dry grain. What is the shape at the tip? 
 Is the crown dented or smooth ? How do the flat sides 
 differ? Study a soaked specimen. How do you 
 account for the changes that have taken place? Care- 
 
 176 
 
FARM CROPS AND HOME PROJECTS 
 
 177 
 
 wjCrown- 
 llStarcbi 
 
 Horny- 
 Starch 
 
 fully remove the covering from a soaked grain. Look- 
 ing at the flat sides decide how many distinct parts 
 there are. The oval shaped portion which is light 
 gray in color is the embryo or germ. With a pen- 
 knife remove the entire embryo using care not to tear 
 it. Lay the rest of the grain aside and examine the 
 embryo. The main 
 part, is the cotyledon. 
 On the upper side of 
 the cotyledon find an 
 indistinct slit. Pull it 
 gently apart length- 
 wise. What do you 
 find on the inside? 
 This rod-like body is 
 the tiny plantlet. It is 
 sometimes called the 
 germ. The end toward 
 the crown of the grain 
 is called the plumule. 
 The other end is the 
 hypocotyl. 
 
 Experiment. Which end will make the root; which 
 the shoot? Place several soaked grains on a piece 
 of moist blotting paper or sand. Turn a tumbler or 
 cup over them in order to retain the moisture. A 
 moist piece of cloth will serve as well as blotting 
 
 Imbrs 
 Stem j 
 
 Embryo./ 
 Boot f 
 
 Fig. 30. 
 
 corn. 
 
 Structure of .a kernel of 
 
178 STUDIES IN SCIENCE 
 
 paper. Keep in a warm place. Examine after three 
 or four days. 
 
 Which grows more rapidly at first, the root or the 
 shoot? Make a drawing of the young plant and ker- 
 nel. On one side name the parts of the embryo; on 
 the other the parts of the plant. See Fig. 30. 
 
 Endosperm. Examine the portion of the grain that 
 was laid aside. This is called the endosperm. How 
 does it compare in size with the embryo? Take a 
 fresh grain and cut it in two lengthwise across the 
 flat surface. Is the endosperm the same kind of 
 material throughout? How many different kinds 
 do you find? 
 
 The function of the endosperm is to furnish food 
 to the plant. To what extent is the plant dependent 
 upon this food supply? 
 
 Experiment. Remove the embryo from a number 
 of seeds. Plant them in soil in a flower pot or can. 
 Place in a warm temperature and keep watered. In 
 another pot plant the same number of whole grains. 
 Let them grow side by side for several weeks until 
 you can decide how great the food value of the endo- 
 sperm is. After four or five weeks dig up a plant that 
 grew from an entire grain and examine the endosperm 
 to see what is left. In what form, solid or liquid, 
 do you find the starchy food material that the plant 
 is using? Where does the plant get food for growth 
 
FARM CROPS AND HOME PROJECTS 
 
 179 
 
 when the endosperm is used up? See Leaves, page 38. 
 
 Germination test. One of the most important 
 things to do, if you are to raise corn, is to make a 
 test of your seed to see whether or not it will grow. 
 There are several ways to do this. The following 
 plan is a good one: 
 
 Make a shallow box or flat three or four inches 
 deep. Place about two inches of clean, moist sand 
 in the bottom. Other soil will do equally well if sand 
 
 Fig. 31. Corn seed tester. 
 
 cannot be procured. With a piece of board make 
 the surface very smooth. With a sharp stick or the 
 end of a ruler divide the surface into squares two and 
 a half or three inches each way. Number the squares 
 from left to right beginning in the upper left-hand 
 corner. See Fig. 31. 
 
 The next step is to get the corn ready for the box. 
 Six grains from each ear should be tested. Take two 
 grains from near the butt on different sides of the 
 
180 
 
 STUDIES IN SCIENCE 
 
 first ear. (Do not use the* ill-formed grains.) Take 
 two from the middle and two from near the tip. Press 
 them slightly into the sand with the germ side up. 
 Number the ear 1. This may be done by sharpening 
 a small piece of shingle or other thin board, putting 
 the number on it and sticking it into the pith at the 
 butt of the ear. Remove six grains from another ear 
 in the same way, number, and continue until all the 
 squares are full of sample grains. Lay the ears aside 
 where they will not be disturbed. To keep the grains 
 moist, place a piece of old muslin or any cotton cloth 
 over them and put about two inches of moist sand 
 on* top. Place in a warm temperature and keep moist. 
 
 GERMINATION TEST OF CORN 
 
 Ear 
 
 Vig. 
 
 Weak 
 
 Failure 
 
 Per cent 
 
 No. 1 
 
 6 
 
 
 
 100 
 
 No. 2 
 
 2 
 
 
 4 
 
 33^ 
 
 No. 3 
 
 
 1 
 
 5 
 
 00 
 
 No. 4 
 
 5 
 
 1 83^ 
 
 The germination box will be ready for examination 
 in four or five days. Begin at one end and carefully 
 roll back the cloth so as not to disturb the grains. 
 Now arrange a table of five columns and place the 
 record of the test in this. In the table the first column 
 indicates the number of the ear. Vig. stands for 
 vigorous. The other terms explain themselves. In 
 the table ear No. 1 shows that all six grains have 
 
FARM CROPS AND HOME PROJECTS 181 
 
 sprouted vigorously and the per cent is of course 100. 
 Ear No. 2 has two vigorous sprouts and four failures, 
 hence is recorded as 33 1/3 per cent. When the 
 entire box has been checked up in this fashion, it 
 will be easy to see which ears should be kept for 
 planting and which discarded. What per cent of a 
 perfect stand of corn would you expect to get from 
 ear No. 2! From ear No. 3 1 etc. 
 
 Experiment. Effect of temperature upon germina- 
 tion. 
 
 
 
 Place grains from the same ear in groups of three 
 or four on moist cloth, blotting paper or sand. Put 
 one group in a refrigerator or other very cool place, 
 another in a moderate temperature, and the third 
 in a very warm place. If possible test the tempera- 
 ture of each place with a thermometer. Watch care- 
 fully for results. What is your decision as to the 
 wisdom of planting corn before the soil is warm in 
 the spring! 
 
 Preparation of seed-bed. What implements do you 
 use in getting your plot or field ready for the seed? 
 If the ground was plowed in the fall it should be 
 disced and harrowed, perhaps rolled in the spring. 
 It is important that the seed-bed be mellow and well 
 pulverized. 
 
 Planting. You must consider the following points 
 in planting: 
 
382 STUDIES IN SCIENCE 
 
 Distance apart of rows : This varies in different 
 localities from 3 to 4 feet, depending upon the rich- 
 ness of the soil. In the corn belt of the Middle West 
 the regulation distance is 3% feet. 
 
 Distance apart of hills: This is usually the same 
 as that of the rows. 
 
 Depth to plant: This depends somewhat upon the 
 condition of the soil. The usual depth is from one 
 and a half to two inches. 
 
 Firming the soil: If you use a corn planter and 
 check row, all of the above points will be settled for 
 you. If you plant by hand, you should firm the soil 
 over the seeds with the back of the hoe. 
 
 You may live in a region where corn is planted in 
 drills instead of hills. The drills are from 3 to 3% 
 feet apart; the grains are planted from 10 to 14 
 inches apart. 
 
 Cultivating. What is the purpose of cultivating 
 corn! You have only to think of your study of weeds 
 and of soil water to answer this question. The depth 
 to cultivate depends upon the condition of the soil. 
 A deep mellow soil may be cultivated somewhat 
 deeper than a compact very moist soil. From your 
 study of corn roots you have learned that too deep 
 cultivation will destroy many of the small roots near 
 the surface and injure your prospect for a good yield 
 of corn. It is usually better to keep the field as level 
 
FARM CROPS AND HOME PROJECTS 183 
 
 as possible rather than to throw the soil up around 
 the hills. You can keep a better soil mulch to con- 
 serve moisture with level cultivation. 
 
 Keep the following record of your corn project: 
 
 1. Size of plot. 
 
 2. Crop raised on plot last year. 
 
 3. Time of planting. Time of harvesting. Variety of corn. Dis- 
 posal of crop. 
 
 4. Expenditures. 
 
 a. Cost of seed. 
 
 b. Rental value of plot. 
 
 c. Cost of labor. (Keep record of hours spent and calculate 
 at price paid for such work.) 
 
 d. Cost of fertilizer. 
 
 5. Receipts. 
 
 a. Yield of plot in bushels. 
 
 b. Value when sold or used. 
 
 c. Value of other parts of the plant if these are used for feed. 
 
 6. Profits. 
 
 a. Yield of plot. 
 
 b. Value at market price. 
 
 c. Net profits. 
 
 d. Net profit per acre. 
 
 PROJECT EIGHT 
 
 OATS 
 
 Material. Samples of oat seeds, plates or boxes for 
 making germination tests. 
 
 Study. If you live in a region where oats are 
 grown you may plan to raise a crop of your own. 
 What time of year are oats sown in your community? 
 Do the farmers raise a larger or smaller acreage of 
 oats than of some other crop? Find out the names 
 
184 STUDIES IN SCIENCE 
 
 oi varieties of oats grown. How do you account for 
 the fact that oats may be planted so much earlier in 
 the season than corn? 
 
 The grain. Remove the chaffy covering from a 
 grain and note the size, color, and shape. Compare 
 it with a grain of wheat, rye and barley. Compare 
 several different varieties of oats with each other as 
 to size and color. 
 
 Purity test. Spread out a small quantity of your 
 sample upon a sheet of white paper. Look closely for 
 foreign bodies of any kind. Put all the weed seeds 
 and trash in one pile and all the oats in another. 
 About what part of your sample is pure oats! How 
 can chaff and light weed seeds be removed from the 
 oats! If you have a fanning mill, run the oats 
 through it. A small amount may be cleaned by hold- 
 ing it high in the air on a windy day and allowing 
 it to fall several feet. A sheet may be spread down 
 to catch it. 
 
 Germination test. The most important thing to 
 know about your seed oats is whether or not nearly 
 every grain will germinate and grow. There is only 
 one way to determine this and that is by making a 
 germination test. Count out one hundred seeds from 
 your sample. Place some moist sand or other soil 
 in a dinner plate or box. Scatter the seeds over the 
 sand, not allowing any two to touch. Press the seed 
 
FARM CROPS AND HOME PROJECTS 185 
 
 slightly into the sand but do not cover. Now turn 
 another plate over this one or cover with a damp 
 cloth. Keep moist. 
 
 How long after planting before the first sprouts 
 appear! Keep watch for two or three days. How 
 many of the seeds fail to sprout! What per cent 
 have sprouted? What percentage of a perfect stand 
 of oats would you expect to get from this seed! 
 
 Preparation of seed-bed. The preparation of the 
 seed-bed for your oats plot depends upon what was 
 raised on the ground last year. If the soil was well 
 cultivated, discing or harrowing may be all that is 
 necessary now. If the ground is hard and compact, 
 it should be plowed and harrowed. 
 
 Planting. What methods of sowing oats are prac- 
 ticed in your neighborhood! How many farmers use 
 drills! How many use broadcast seeders! How much 
 oats will be required to plant an acre! Some farm- 
 ers use from three to three and one-half bushels. 
 Others claim that they get a better yield by sowing 
 from one and a half to two bushels. 
 
 The chief rule to follow as to time of planting is 
 to sow your oats in the spring as early as the soil can 
 be worked. In the South they are sown in the fall 
 and are known as winter oats. 
 
 Oats belonged originally in a cold climate. It is a 
 crop of northern regions, especially of Sweden and 
 
186 STUDIES IN SCIENCE 
 
 Northern Bussia. Some of our best varieties origin- 
 ated in these countries. This is the reason we plant 
 them so early in the spring. Watch to see whether 
 a frost injures the young plants. 
 
 Treating for smut. Smut is a disease which attacks 
 oats decreasing the yield in many places from 15 to 
 25 per cent. You can prevent smut by treating the 
 seed with formalin. (See page 237.) You may be 
 interested to make an experiment. Measure off two 
 tracts of ground of exactly the same dimensions. In 
 one sow oats that have been treated with formalin. 
 In the other sow untreated seeds. When the plants 
 are heading out examine them for smut and deter- 
 mine whether the formalin treatment was effective. 
 If possible get the exact yield from each plot and 
 estimate the loss per acre due to smut. 
 
 Observation of growing plants. Watch the habit of 
 growth of the oats plants. When they are six weeks 
 or two months old examine them and determine how 
 many stems grow from one root. What kind of leaves 
 has the plant! Note the plants when they blossom 
 or head out. This kind of branching is called a 
 panicle. If the branches are all on one side, it is 
 called "side oats." Make a careful study of the 
 panicle. Note where the grains are attached. Look 
 in the head for grains of different sizes. 
 
 When your crop is about ready to harvest look 
 
FARM CROPS AND HOME PROJECTS 
 
 through it for heads that seem superior to the others 
 in size and weight. If you are interested in breeding 
 up your oats to a better yield, cut out these heads, 
 thresh them and plant them in a plot by themselves 
 next year. You will in this way get seed enough to 
 plant several acres in a few years and perhaps 
 increase the yield many per cent. 
 
 Keep the following record of your oat project: 
 
 1. Date of planting. 
 
 2. Date of harvesting. 
 
 3. Yield of plot. 
 
 4. Yield per acre. 
 
 5. Expenditures. 
 
 a. Value of seed. 
 
 b. Rent of plot. 
 
 c. Cost of labor. 
 
 d. Cost of threshing. 
 
 6. Receipts. 
 
 a. Value of oats at current price. 
 
 b. Value of straw. 
 
 c. Net profits. 
 
 d. Net profit per acre. 
 
 PROJECT NINE 
 
 WHEAT 
 
 If you planted a plot of w r lieat in the fall, make 
 field observations of the plants. Note the condition 
 of the field at the close of winter. Has any part of it 
 been killed? Dig up a plant and note the length of 
 the root system. If any new leaves have developed 
 
188 STUDIES IN SCIENCE 
 
 this spring, determine from what part of the plant 
 they grew. Watch occasionally the development and 
 growth of the entire plant, especially of the flowering 
 heads, until harvest. When does the head first 
 appear? Note the change of color that takes place 
 as the wheat matures. 
 
 Keep a record of your wheat plot using the items 
 suggested for oats. 
 
CHAPTER XII 
 
 TREES 
 
 Flowers and leaves. Keep a simple flower record 
 of the trees of your community. Note the date of 
 blossoming; the color and kind of flowers; date of 
 
 opening of leaf buds. What 
 trees have separate flower 
 and leaf buds ! Which have 
 a combination of the two! 
 Some of the maples and 
 elms blossom very early, 
 long before the leaf buds 
 open. In the South the 
 swamp maple begins to 
 open its beautiful red flow- 
 ers the latter part of Febru- 
 ary or the first of March. 
 Farther north the silver 
 and red maples, as well as 
 
 Fig. 32. Flowers of 
 American Elm in April. 
 
 the 
 
 members of the elm family, 
 blossom the latter part of March or the first of April. 
 These blossoms while very small are wonderfully in- 
 teresting and should be studied at close range. Some 
 
 189 
 
190 
 
 STUDIES IN SCIENCE 
 
 of them are perfect, having both stamens and pistils; 
 this is always true of the elms. Other trees have two 
 distinct kinds of flowers, staminate and pistillate. 
 None of these early flowers have brightly colored 
 petals. 
 
 The growth of trees. Watch terminal buds of sev- 
 eral different species of trees as they open and 
 develop. How long is the new part of the twig by 
 
 . , the time the 
 
 leaves are well 
 open? Where do 
 new leaves con- 
 tinue to appear! 
 Compare several 
 species as to the 
 rapidity with 
 which the twigs 
 lengthen. Watch 
 also the develop- 
 ment of lateral 
 buds. What do 
 they produce? 
 
 Fig. 33. 
 May. 
 
 Fruit of the American Elm m 
 
 Compare the 
 growth of twigs from lateral with those from terminal 
 buds. 
 
 What other growth does a tree make besides put- 
 ting out new twigs and lengthening its branches? 
 
TREES 
 
 191 
 
 To answer this question you should have some cross 
 sections of twigs and branches. If people in the 
 neighborhood are pruning their trees make some 
 sections of different sized branches. Each section 
 should be cut straight across and should be an inch 
 or two in length. If some one cuts down a tree get 
 a few large sections. These may be kept in the school 
 room for years. 
 
 Besides the above make some sections of a one, 
 two, and three-year-old twig. Willow or poplar are 
 good for this study. Ex- 
 amine the one-year sec- 
 tion first. How many 
 distinct structures do 
 you find ? For names see 
 Fig. 35. Peel the bark 
 from some of the fresh 
 twigs. How does the 
 wood underneath look? 
 Rub your finger over it. 
 
 How does it feel? Ex- Flowe of the Nor " 
 
 amine in the same way 
 the inside of the bark that you removed. 
 
 Compare the two and three-year-old sections with 
 those of one year, noting differences. How do the 
 oldest sections that you have differ from the younger 
 ones? What do the rings tell? What indications 
 
192 STUDIES IN SCIENCE 
 
 are there that the tree grew faster some years than 
 others! How does the bark on the young stems 
 differ from that on the older branches or the trunk? 
 Why is the older bark so rough while the young 
 twigs are smooth? Examine a number of twigs and 
 branches of varying ages to see if you can solve this 
 problem for yourself. 
 
 Discussion. The growth of a tree is not limited 
 to the making of new twigs and the lengthening of 
 the old ones. From your study of the cross section 
 
 Fig. 35. 1. Cross-section of a twig one-year-old, a, Outer bark; 
 b, Inner bark; c, Cambium layer; d, Wood layer; e, Pith. 2. Cross- 
 section of a twig two-years-old, a and b show the two rings of wood 
 growth. 
 
 you know that there is a growth in thickness. Each 
 ring of wood usually shows a year's growth. The 
 growth takes place in the sticky layer that you found 
 between the bark and the wood. This is known as the 
 cambium. Not only does a new layer of wood grow 
 here each year, but a new layer of bark also. 
 
 The outer layer of bark does not grow, and when 
 new layers of wood and bark grow on the inside the 
 outside has to stretch. After a time it can stretch 
 
TREES 183 
 
 no more and then it cracks. If you look at branches 
 of different ages you see that the cracks grow deeper 
 and more numerous year by year until finally there 
 are the deep fissures that you find in the oldest part 
 of the tree. 
 
 Do you know any tree whose bark on the trunk 
 remains smooth until the tree is quite old? What 
 must be true of 
 the growth when 
 this is the case? 
 The bark and the 
 wood grow at 
 about the same 
 
 Fig. 36. Pistillate flowers of silver maple. 
 
 rate for a number 
 
 of years. The wild cherry and the white birch are 
 good examples of this. For a long time the trunk is 
 as smooth as the branches, then little by little the 
 bark cracks and scales, making quite a rough surface 
 when the tree is old. 
 
 If you have a section of a large tree you can prob- 
 ably see a distinct difference between the wood at 
 the center and that toward the outside. The inside 
 portion is called heartwood; the outside, sapwood. 
 The heartwood, after a number of years, becomes dry 
 and hard. It is really dead but it still helps to sup- 
 port and strengthen the tree. However, trees may 
 live a number of years with much of the heartwood 
 
194 
 
 STUDIES IN SCIENCE 
 
 decayed. You liave no doubt seen living trees that 
 were quite hollow. Name one or more species of trees 
 in which the heartwood is likely to decay while the 
 tree continues to grow. 
 
 The food of trees. Since trees grow they must 
 have food. If you bore a small hole in a map]e tree 
 in the early spring*, or break the tip off a branch, sap 
 runs out. If you taste this sap you find that it is 
 sweet. Where did it get the sugar that is in it ? From 
 
 your fall study you know it 
 was manufactured last summer 
 by the leaves and was stored in 
 the tree during the winter. 
 You may think of the leaves of 
 trees as factories that make 
 food for the entire tree. The 
 roots take in water and some 
 minerals from the soil which 
 travel upward through the 
 
 Fig. 37. staminate flow- stem to the leaves ; the leaves 
 
 ers of silver maple. 
 
 themselves take a, gas, carbon 
 
 dioxide, from the air, and with these raw materials, all 
 day long in the sunlight during the spring and sum- 
 mer, they manufacture plant-food. Some of this is 
 used for growth during the summer, but much of it 
 accumulates in the twigs, stems and roots for future 
 use. 
 
TREES 19j 
 
 Our native woods. If possible, visit a native woods. 
 Stand under the trees and look up. To what extent 
 do the crowns cover the overhead space? How many 
 different kinds of trees do you find! Which species 
 are largest! Which medium in size! Note the sap- 
 lings, trees from four to ten or even fifteen feet in 
 height. Are they the same species as the largest 
 or the medium size trees! How numerous are the 
 seedlings, young trees not more than three feet high! 
 What different species do they represent! If the 
 woods are left undisturbed, what species will be most 
 abundant fifty or one hundred years hence! What 
 shrubs do you find growing under the trees! What 
 wild flowers! Examine open spaces. Note what 
 plants are growing there that are not found in the 
 dense woods. How do you account for the difference! 
 
 What is the condition of fallen logs or old stumps! 
 Look for branches that have recently fallen. Exam- 
 ine the spots on the trees from which they have 
 dropped. If these trees are used for lumber, the base 
 of every branch will appear as a knot in the boards. 
 From what kind of tree can clear lumber, that is 
 boards free from knots, be obtained! 
 
 What use is made of wooded regions in your local- 
 ity! How many are pastured! Do the stock injure 
 the trees in any way! How many are kept as wood- 
 lots by their owners! What different wood products 
 
]96 STUDIES IN SCIENCE 
 
 may a wood-lot well cared for produce! To what 
 extent are the woods in your part of the state disap- 
 pearing? Are there any tracts in your county that 
 have been set apart for the use of the public? What 
 do you think of the plan of having a few areas of our 
 native woods in every county preserved for all time 
 for the people? They could be used as recreation 
 grounds for the community, but, better than that, 
 for study purposes by all the school children. 
 
 Forests and forestry. We usually call small areas 
 of trees woods or woodlands, but the large tracts 
 which are used for lumbering purposes are known as 
 forests. Lumbermen classify the forests into hard 
 wood and soft wood. Hard wood forests comprise 
 the broadleaf trees as walnut, maple, oak, birch and 
 mahogany. Soft wood forests are the cone bearing 
 trees such as pines, cedars and spruces. Your geog- 
 raphy will tell you where these various forests are 
 found. 
 
 Forests have many enemies such as fires, insects, 
 fungous diseases and wasteful methods of lumbering. 
 The art of cultivating, managing and caring for for- 
 ests is known as forestry. The forestry branch of 
 the U. S. Department of Agriculture has given much 
 attention in recent years to the better management 
 and care of our great forests. It tries to prevent 
 fires, to combat insect pests, and to introduce the 
 
TREES 197 
 
 best methods of lumbering, so that by the conserva- 
 tion of the young trees the lumbering industry may 
 be kept permanent. It is also attempting to raise 
 timber crops in treeless regions of the West. 
 
 Uses of trees. What are trees good for? You have 
 only to look around in your home and school to 
 realize how very useful trees are. Make a list of all 
 the things in and about your home, school, church, 
 stores, street, and farm that are made wholly or in 
 part from the wood of trees. Make a second list 
 which includes trees that furnish food of some kind. 
 Make a third list in which you include the value of 
 trees in affording you and other people pleasure. 
 
 The first and second lists give you some idea of the 
 great value of trees in the industrial world. They 
 not only furnish quantities of food and the vast 
 amount of materials used in buildings, furniture, 
 machinery, paper, etc., but at the same time they 
 afford employment to thousands of people in lumber 
 regions, in factories, in carpentry, in paper mills, 
 etc. Your geography will tell you something of the 
 great centers of these activities. 
 
 The third list helps you to appreciate the value 
 of trees in your own life. They afford shade and 
 shelter, provide nesting places for birds, and make 
 our homes, public school grounds, and the entire 
 landscape beautiful. Why do artists so commonly 
 
198 STUDIES IN SCIENCE 
 
 put trees into pictures? Where are trees most beau- 
 tiful to you! 
 
 Trees on home grounds. Study the trees about 
 your homes and other places in your neighborhood. 
 How many of them are native trees! How did they 
 happen to be there! Did they grow wild or were 
 they planted! Which of them do you like best! Is 
 there any one tree in the neighborhood that you con- 
 sider especially beautiful? If it is an old tree, find 
 out all you can about its history. What street or 
 road has the most beautiful row of trees! Which 
 do you think is more attractive, a street planted the 
 entire length with one species of tree, or one planted 
 with a number of species! 
 
 Select the home in your community that has its 
 trees arranged to give the most beautiful effect, an 
 effect that makes the trees and buildings look as if 
 they belong together. 
 
 Planting trees on home grounds. Trees about a 
 home may add much or little to its attractiveness 
 according to the trees used and the manner in which 
 they are set out. Simple rules to follow in planting 
 home grounds are: 1. Choose hardwood, long lived 
 trees, not the shorter lived, more rapid growers. 
 With a few rare exceptions choose native rather than 
 foreign trees. 2. Place the trees at the sides and 
 rear of the house, not in front. You do not want 
 
TREES 
 
 199 
 
 them to screen the building, but rather to make a 
 background and natural setting for it. 3. Let the 
 height of the building help to determine the species 
 of trees to use. Cottages and bungalows to make a 
 pleasing landscape picture should have low trees 
 
 Fig. 38. Spraying large trees. 
 
 nearby. On the other hand, high buildings require 
 some tall trees to frame them in. 
 
 Care and protection of trees. You should be inter- 
 ested in trying to keep the trees in your community 
 in as good a condition as possible. Trees need care 
 and protection, and while you may not be able to 
 do much active work you can do something. Make 
 a simple survey of the trees in your block or district 
 
200 STUDIES IN SCIENCE 
 
 to find out whether or not they need attention. How 
 many do you find that have been injured in some way! 
 Determine, if possible, what caused the injury. Are 
 any insects feeding upon the trees! Look on the 
 bark for scales. Examine the old trees for unhealthy 
 conditions as shown by decaying spots or fungous 
 growths. Look for dead branches that should be 
 cut out. Do you find guards around young trees? 
 Are there any that should be protected in this way 
 but are not! Report what you find to your teacher 
 or to the officer whose business it is to look after 
 the welfare of the trees. Another thing you may do 
 is to be careful not to injure trees yourself. Avoid 
 swinging on young trees or breaking off twigs and 
 branches. You may help to work up a sentiment in 
 your neighborhood that will go far toward making 
 other people, both children and adults, take a greater 
 interest in caring for the trees. 
 
PART TWO 
 FALL STUDIES 
 
 CHAPTER XIII 
 
 INSECTS 
 
 Material. Insects of the garden, orchard, fields 
 and home; wide-mouthed bottles or tumblers; several 
 pint and quart jars; a flower pot with a lantern globe 
 or lamp chimney; a wire cage or vivarium; a small 
 hand lens. 
 
 A vivarium. For the foundation of this use a 
 shallow box a foot and a half or two feet long, 
 six inches wide and three inches deep. Nail upright 
 in each corner a flat piece of board fifteen inches high, 
 about an inch wide and half an inch thick. Com- 
 plete the frame by nailing pieces of board to the top 
 of the uprights. Cover the sides with wire screen 
 or mosquito netting, and place a board or pane of 
 glass on the top for a cover. See Fig. 39. 
 
 A simple cage may be made from an ordinary shoe 
 box. Cut rectangular pieces out of the top and bot- 
 tom and sew in wire screening or mosquito netting, 
 
 201 
 
2012 STUDIES IN -SCIENCE 
 
 tying a string around the box to keep the lid on. 
 Stand it on one side and you can easily watch the 
 movements of insects within. 
 
 If you wish to make a collection of insects, a 
 cyanide jar is necessary. To make one place five 
 cents' worth of cyanide of potassium in the bottom of 
 a wide mouthed bottle or pint fruit jar. Handle the 
 
 Fig. 39. A vivarium or insect cage stocked with insects. 
 
 cyanide very carefully; do not touch it with your 
 fingers. Make a stiff paste of plaster of Paris and 
 water. Pour this over the cyanide, covering it about 
 an inch or an inch and one-half in depth. Allow the 
 bottle to stand open two hours, then close it tightly 
 and keep closed except when putting insects in or 
 taking them out. Label the jar POISON. 
 
 Garden pests, Make a list of all the insects you 
 
INSECTS 
 
 203 
 
 have found in your garden this season. Choose for 
 detailed study any that you find on your plants now. 
 The cabbage worm. Look on cabbage plants for 
 worms or larvae. On what part of the leaves are 
 they? What are they doing! How many different 
 
 Fig. 40. The common cabbage worm (Pontia rapae). a, Female 
 butterfly; b, Egg; c, Larva, or worm, in natural position on cabbago 
 leaf; d, Suspended chrysalis, or pupa. 
 
 sizes are there? Do they look as if they were all the 
 same species? Collect a number of leaves with the 
 worms on them and place them in a box in the school 
 room for further study. Look carefully at one larva 
 and note everything that you see. Describe the body 
 
204 STUDIES IN SCIENCE 
 
 covering. What is the number of feet? How do the 
 feet on different parts of the body differ from one 
 another? What are the uses of the different kinds! 
 
 Watch a larva feeding. How does it eat? What 
 kind of mouth has it? Determine this by observing 
 the partially eaten leaves. Put several larvae into 
 a box or insect cage and give them fresh leaves every 
 day. Watch for changes. Describe the new form. 
 This is called a pupa, the plural is pupce. Deter- 
 mine how the pupa is attached to the box. Examine 
 it with your lens and describe what you see. Keep 
 the box with the pupae so that you may later see the 
 adult insects. 
 
 If you have two kinds of larvae compare them 
 noting differences. How do they differ in the pupa 
 stage ? 
 
 The butterfly. Watch white butterflies hovering 
 over the cabbage plants. What do they seem to be 
 doing? Look very closely on the leaves especially 
 on the under side for eggs. These are small cream 
 colored specks that stand up on end. Examine one 
 with your lens and describe it. Capture a butterfly, 
 place it in a clear glass bottle and note its colors, the 
 number of feet, the wings, the kind of antennae, 
 (feelers) and the mouth. 
 
 Are cabbage-worms very destructive? What meth- 
 ods of combating them do you know? 
 
INSECTS 205 
 
 Discussion. If you saw all the legs of the cab- 
 bage-worm, you noticed three pairs of rather pointed 
 ones near the head, four pairs of wide ones near the 
 middle, and one wide, flat pair close to the hind part 
 of the body. The three near the head are called true 
 legs; all of the others are prop legs. The prop legs 
 are used for clinging as well as for crawling. 
 
 Cabbage-butterflies lay their eggs upon cabbage 
 leaves. These hatch into small larvae which have 
 jaws or biting mouths with which they nibble holes 
 in the leaves. When they are ready to change into 
 pupae, they fasten themselves to some object by 
 means of a few silk threads bound about the middle 
 part of the body. Then they shed their skins and 
 become pupae. During the summer and early fall 
 the insect remains in the pupa stage from a week to 
 ten days. Those that pupate late in the fall remain 
 in this stage all winter. When the pupa changes to a 
 butterfly, the skin splits along the back and the but- 
 terfly emerges. The pupa skin, as well as the pupa 
 itself, is often called a chrysalis. 
 
 If you had two kinds of larvae, you found that 
 the one with prominent sections, when it went into 
 the pupa state, spun a thin white cocoon and changed 
 to a dark brown pupa. This larva produces a cab- 
 bage-moth instead of a butterfly. It remains in the 
 pupa stage about ten days and then emerges, a small, 
 
20G STUDIES IN SCIENCE 
 
 dark-colored moth, the kind that people often call 
 moth millers. Compare the moth with the butterfly 
 noting differences. 
 
 Tomato-worm. If you have tomato plants, you may 
 find larvae of the tomato sphinx-moth on them. Study 
 these as you did the cabbage-worm. If you wish to 
 watch them through their life history, you must pro- 
 vide soil in which they may pupate. Fill a fruit jar 
 about half full of garden soil. Firm it down, then 
 place the worm in it with tomato leaves for it to 
 feed upon. When the larva is ready to pupate it 
 pushes down into the soil, makes a mud cell perfectly 
 smooth on the inside, then sheds its larva skin and 
 becomes a pupa. Sometimes when you spade up your 
 garden in the spring, you find the brown pupa of 
 the tomato-worm. It has a loop on one side which 
 resembles a handle. This is a case for the long suck- 
 ing tube of the moth. Set the jar in which the worm 
 has pupated in a cool place and occasionally moisten 
 the soil a little especially in the early spring. Place 
 a small twig in the jar to which the moth may cling 
 when it emerges from the ground. These moths 
 appear from April until the latter part of May or 
 even June, depending upon the latitude. 
 
 You have probably discovered that while the larvae 
 of moths and butterflies have biting mouths with 
 which they eat leaves, the adults have sucking mouths 
 
INSECTS 207 
 
 and feed upon the nectar of flowers. Many moths 
 are quite as beneficial as bees in carrying pollen from 
 one flower to another. All butterflies and moths have 
 the same kind of life history as the cabbage-worm 
 and the tomato-worm. They have four distinct stages : 
 the egg, larva, pupa and adult. Insects that make 
 this complete change in their form are said to have 
 complete metamorphosis. 
 
 Squash -bug. Look on your pumpkin and squash 
 vines for a flat, dark gray insect a little more than 
 half an inch in length. Where on the plants do you 
 find them? What are they doing? Visit the plants 
 early in the morning, again during the warm part 
 of the day, and in the evening. How do the insects 
 differ in their behavior at these different times ? How 
 many stages of development do you find among them? 
 How do the young differ from the adults ? Place some 
 of the young in a jar with a few fresh leaves and keep 
 them for a few days. What happens? How do they 
 accomplish the change? Look in the jar for cast-off 
 skins. 
 
 Examine the front part of the head of the adult 
 squash-bug for the mouth. How far back does the 
 sucking tube extend? How is this used in procuring 
 food? Place a few of the insects in a fruit jar with 
 squash or pumpkin stems or a small piece of the 
 fruit. Watch them eat. Describe the wings of the 
 
208 
 
 STUDIES IN SCIENCE 
 
 insect. About what portion of one overlaps the other? 
 Look for inner wings. Is the squash-bng as great a 
 flier as moths or butterflies! 
 
 Fig. 41. The common squash-bug (Anasa tristis). a, Newly 
 hatched nymph; b, Second stage nymph; c, Third stage nymph; d, 
 Fourth stage nymph; e, Fifth stage nymph; f, Adult; g, Egg mass. 
 (All about twice natural size.) 
 
 Aphids. Look on the leaves of cabbages, turnips, 
 nasturtiums or other plants for small plant lice called 
 aphids. Some lie flat, others resemble tiny flies. Ex- 
 amine them carefully and note the number of stages 
 represented. How do the winged individuals differ 
 
INSECTS 209 
 
 from the wingless! What kind of mouths have they? 
 To determine this, hold the leaf on a level with your 
 eye so that you can see under the insect and find the 
 sucking tube inserted in the leaf. Are there any other 
 insects among the aphids! If so, what are they 
 doing I (See Beneficial Insects, page 223.) In what 
 respects do aphids resemble squash-bugs! 
 
 Discussion. The squash-bug differs from moths and 
 butterflies in that it does not have the four complete 
 stages in its development. The young when it hatches 
 from the egg has the same form as the adult except 
 that it is smaller and lacks wings. As it grows it 
 sheds its skin or molts. After the second molt, the 
 wings appear as little flat pads on the back. After 
 the last molt the wings are fully developed. Insects 
 that have this kind of a life history are said to have 
 incomplete metamorphosis. The young are called 
 nymphs. 
 
 Aphids have the same kind of mouths as squash- 
 bugs; that is, a piercing sucking tube. They also 
 have incomplete metamorphosis, but they do not have 
 the same kind of overlapping wings. They are among 
 the most destructive of pests. Few plants are free 
 from them. They have a life history differing from 
 most other insects. 
 
 One of the most destructive of these insects is the 
 corn-root aphis, which feeds upon the roots of corn. 
 
210 STUDIES IN SCIENCE 
 
 Its life history is similar to that of all other aphids 
 except that the eggs of all are not cared for by ants. 
 
 The female of the corn-root aphis lays shiny black, 
 oval eggs in the ground during the fall months. Lit- 
 tle brown ants find these, carry them to their under- 
 ground homes, and keep them safe through the winter. 
 They often carry the eggs out into the sunshine dur- 
 ing the warm part of the day and back into the 
 burrows at night. These eggs hatch in the early 
 spring into young aphids. The ants at once place 
 them upon the roots of smart weeds or some other 
 plant. When corn is beginning to grow, the ants place 
 the aphids on the corn roots, from which they suck the 
 juices with their sharp sucking tubes. The ants get 
 their pay for all this work in the form of honey dew, 
 a sweet substance which the aphids throw out of 
 their bodies. 
 
 Each aphid that hatches from an egg in the spring 
 is called a stem-mother. In less than a month this 
 stem-mother begins to reproduce young. All these 
 are females which in a month's time begin also to 
 produce young. So in less than two months the stem- 
 mother may become the ancestor of thousands of 
 young lice. This goes on all summer. 
 
 Most of the aphids are wingless. Once in a while 
 there is a generation that has wings. These fly away 
 to some other part of the field or to another field. 
 
INSECTS 211 
 
 Some of them drop to the ground, and are found by 
 ants which carry them at once to the corn roots. In 
 the fall a brood of males and females is produced. 
 These females are the ones that deposit eggs for the 
 new stem-mothers next year. You can readily see 
 why the destruction of the ants' homes should be 
 encouraged. 
 
 One of the methods employed to destroy these pests 
 is to break up the ground as early as possible in the 
 spring, and then before corn planting go over it once 
 or twice with a disc or cultivator in order to destroy 
 the smart weeds and as many of the ants' nests as 
 possible. 
 
 Cucumber beetles. During the fall you may find 
 in the flowers of squash or pumpkin and on some of 
 your flowering plants small cucumber beetles. Often 
 there are two species; one a dull green spotted with 
 black, the other with black and yellow stripes. 
 Determine if possible what the beetles are doing in 
 the flowers. Capture some of them and find out all 
 you can about them. How do they compare with 
 other insects studied as to hardness of body? How 
 many legs have they? How many pairs of wings? 
 How are the outside wings placed in relation to each 
 other? How do the inner ones compare in length 
 with the outer? What kind of a mouth has the beetle? 
 
 Discussion. Cucumber beetles are among the worst 
 
212 
 
 STUDIES IN SCIENCE 
 
 garden pests. They are very destructive to cucum- 
 ber plants as well as to melons of all kinds. They do 
 most of their mischief in the larva stage. The adult 
 beetles in the fall are fond of pollen. That is why 
 you find them feeding in the flowers. They hide away 
 during the winter under leaves or other rubbish and 
 come out about the time the cucumber plants and 
 other cucurbits are beginning their growth. They 
 
 Fig. 42. The striped cucumber beetle (Diabrolica vittata). a, 
 Beetle; b, Larva; c, Pupa. (Much enlarged.) 
 
 visit the plants for two purposes; to feed upon the 
 young leaves, and to lay their eggs at the lower part 
 of the stem. The eggs hatch into worm-like larvae 
 that bore into the stem and roots, often killing the 
 plant. 
 
 Like all beetles they have biting mouths, hard 
 outer wings that meet in a line down the middle of 
 
INSECTS 
 
 213 
 
 the back, and membraneous inner wings that are 
 used for flight. These wings are longer than the 
 outer ones and when not in use are folded back under 
 the protective hard ones. 
 
 - - Q 
 
 THORAX 
 
 Fig. 43. Parts of an insect: A, Antennae; B, Compound eye; 
 C, Mouth; D, Palps; E, Outer wing; F, Inner wing; G, Ovipositor; 
 H, Foot; I, Spiracles or breathing pores. 
 
 While we have chosen for study types of insects 
 that are likely to be found in gardens, you should 
 make an effort to get acquainted with other insects 
 that are found about your home, school and farm. 
 
 Use the following outline in keeping a record of 
 your insect studies. Keep any larvae that you find 
 in glasses or boxes, feed them and watch their devel- 
 opment. In most cases the plants upon which you 
 find the insects will determine what to feed them. 
 
214 STUDIES IN SCIENCE 
 
 , 
 
 INSECT RECORD 
 
 1. Name: 
 
 2. Stage of development: larva, pupa, adult, or, if an insect with 
 incomplete metamorphosis, nymph. 
 
 3. Where found: 
 
 4. Characteristics: 
 
 a. Size small, medium, large, or length in inches. 
 
 b. Body covering hairs, spines, smooth skin, etc. 
 
 c. Color or colors. 
 
 d. Antennae long, short, hair-like, elbowed, knobbed, feath- 
 ery, scaly, etc. 
 
 e. Eyes large, small, position. 
 
 f. Legs number, special features. 
 
 g. Wings number, special features. 
 
 5. Habits: movements, active in daylight, at night. 
 
 6. Kind of development: complete metamorphosis, incomplete 
 metamorphosis. 
 
 7. Pest, benefactor or neutral. 
 
 8. If pest, how controlled. If benefactor, what does it do that is 
 beneficial? 
 
 9. Remarks. Any facts of interest not noted above. 
 
 Insects and health. The house-fly and the mos- 
 quito are of special interest because they carry con- 
 tagious diseases from one person to another. 
 
 Mosquitoes. Mosquitoes breed in standing water. 
 You may find the young, or larvae, in pools, ponds, 
 rain barrels and tin cans that have been thrown into 
 the rubbish heap and are partly filled with water 
 from rains. If you find any of the larvae (a common 
 name for them is wrigglers) place some in glasses 
 of water and watch them. Determine how they move 
 about, how they breathe, and how they eat. Tie 
 netting over some of the tumblers and keep till the 
 
INSECTS 215 
 
 insects change to the adult mosquitoes. Place a small 
 amount of kerosene on the surface of the water in 
 one tumbler and note the effect. 
 
 The mosquito larvae that you find abundant in rain 
 barrels, tin cans and pools belong to the genus called 
 Culex. There are a number of different species of 
 these, some much larger than others. 
 
 If you observed the larva carefully you noted that 
 when at rest it remains near the surface of the water 
 with the head end extending obliquely downward. 
 At the back part of the body is a small tube-like pro- 
 jection which reaches the surface of the water. This 
 is the breathing tube, so, although the insect lives 
 in water, it breathes the air above the water. Around 
 the mouth the brushes of hair that you see constantly 
 moving are making a current of water which brings 
 food to the larva. It eats tiny one-celled plants and 
 animals and bits of decaying matter. It remains in 
 the larval stage from five to ten days according to 
 the temperature. The warmer the weather the more 
 rapidly it grows. 
 
 You probably noticed that some of the wrigglers 
 differ from the larvae. They are darker and the front 
 part of the body is thick and curved. Each of these 
 is a pupa. The pupa breathes by means of two tube- 
 like projections on the back, so it floats in the water 
 with the head up instead of down. It does not eat 
 
216 STUDIES IN SCIENCE 
 
 in this stage. In from five to seven days the pupa 
 skin splits open along the back and the mature mos- 
 quito works its way out. It floats a short time upon 
 the empty skin while the wings are drying, then it 
 flies away. By putting mosquito larvae into a jar 
 of water and tying cheese cloth over the top you can 
 work out the entire life history. 
 
 The Culex mosquitoes, so far as known, are not 
 dangerous; that is, they do not carry diseases. They 
 are, as everyone knows, exceedingly annoying. 
 
 It is only the female that bites and sucks blood. 
 The male feeds upon the nectar of flowers. The hum- 
 ming sound made by the mosquito is produced by the 
 vibrations of the wings. 
 
 The Anopheles mosquito is more than annoying. 
 It transmits malaria of all kinds; hence it is often 
 called the malaria mosquito. The larva differs from 
 the Culex in that it floats almost parallel with the 
 surface of the water instead of obliquely. The pupa 
 is very similar to that of the Culex. The adults of 
 the two kinds are somewhat different. The Anopheles 
 have dark spotted wings. The Culex when resting on 
 a wall remains with the body straight; the Anopheles 
 holds the hinder part of the body away from the wall 
 thus making an angle. Culex mosquitoes are to a 
 certain extent active during daylight. Anopheles are 
 active only after six o'clock in the evening. 
 
INSECTS 217 
 
 How mosquitoes transmit malaria. The malaria 
 germ is a tiny one-cell animal that passes through one 
 stage of its life in man and another stage in the body 
 of the mosquito. In man these germs live in the red 
 blood corpuscles, feeding upon them. When a germ 
 reaches a certain size in the blood corpuscles it 
 divides into a number of distinct individuals, which 
 float about for a while in the blood, then again enter 
 the corpuscles and go through the same process of 
 division. 
 
 If a malaria mosquito sucks blood from an infected 
 person, a large number of these small germs called 
 spores are taken into the stomach of the mosquito. 
 Here they undergo certain changes and then pass 
 through the wall of the stomach into the body. They 
 finally reach the salivary glands. If now the mos- 
 quito bites a person who is free from malaria, some 
 of these germs flow with the saliva into the blood. 
 They enter the corpuscles, feed and multiply and 
 cause chills and fever or some other form of malaria. 
 
 So far as is known this is the only way that malaria 
 is transmitted; that is, it can get from one person to 
 another only through the agency of mosquitoes. 
 Sometimes, however, the spores may remain inactive 
 or dormant for a long period in the blood of a person 
 who has had malaria, then suddenly become active 
 and produce the disease. 
 
218 STUDIES IN SCIENCE 
 
 It is very evident that all that is necessary to eradi- 
 cate malaria ' is to get rid of malaria mosquitoes. 
 Since these insects breed only in water it is not a 
 difficult task in most regions to exterminate them. 
 Draining ponds, covering pools that cannot be drained 
 with crude oil or kerosene, screening rain barrels and 
 preventing the accumulation of tin cans or other rub- 
 bish, will in a short time entirely rid a community 
 of these pests. The fact is, that in many parts of the 
 country they are already kept well under control. 
 
 Where drainage is not possible kerosene may be 
 used to kill the larvae and pupae. The oil spreads 
 over the surface of the water making a thin film on 
 top. The insects cannot penetrate this with their 
 breathing tubes so they are entirely shut off from air 
 and soon die. This method has been used extensively 
 in some of the swampy regions of the East and has 
 proved very effective. 
 
 Yellow fever is transmitted from one person to 
 another by the yellow fever mosquito in about the 
 same manner that malaria is. The disease has de- 
 creased remarkably during the last ten years because 
 the mosquitoes are not allowed to breed as formerly. 
 
 House-fly. The house-fly is even a greater menace 
 to health than mosquitoes. Capture a house-fly, put 
 it in a glass or bottle and examine it. Describe its 
 eyes, wings, legs. Put a bit of sugar or some other 
 
INSECTS 
 
 219 
 
 food in the glass and watch to see how the fly eats. 
 The long projection that you see is the tongue. This 
 is used to lap up liquid food. When the fly eats a 
 hard substance like sugar it first moistens it and then 
 laps it up. 
 
 The life history of the fly is familiar to almost 
 everyone. It has complete metamorphosis, passing 
 through the four stages from the egg to the adult 
 in less than two weeks. Its chief breeding places are 
 
 
 Fig. 44. The common house fly (Musca domestica), showing 
 puparum, adult, and larva. (All enlarged.) 
 
 stable manure, outdoor closets and other places where 
 there is an accumulation -of decaying vegetable or 
 other organic matter. 
 
 The eggs, during the warm summer months, hatch 
 within twenty-four hours after they are laid. The 
 larvae are known as maggots. They are white in 
 color and feed ravenously upon the food material with 
 which they are surrounded. In from five to seven 
 
220 
 
 STUDIES IN SCIENCE 
 
 days they reach their full size as larvae; they then 
 crawl out of the food material into a dry place where 
 they change to pupae. A pupa is brown in color and 
 about as large as a grain of rice. The pupa stage 
 lasts from four to six days in hot weather. In cool 
 weather it may last ten or twelve days or it may 
 
 remain in this stage 
 over winter. The adult 
 then emerges and in a 
 few days is ready to de- 
 posit eggs. Each fly 
 lays from two hundred 
 and forty to four hun- 
 dred eggs. 
 
 For a long time it was 
 supposed that house- 
 flies spend the winter 
 only in the adult stage, 
 but recent experiments 
 seem to show that prob- 
 ably most of them pass 
 the winter in the pupa stage. 
 
 There is little question that the house-fly is a car- 
 rier of typhoid fever, dysentery, cholera and tuber- 
 culosis. It carries the germs of these diseases on its 
 sticky feet and on the hairs of its body. When it 
 alights on food, as it often does, some of the germs 
 
 Fig. 45. The dingy 
 (Feltia subgotMca). a, Moth 
 adult, with, wings expanded; b, 
 Larva, or worm, in curled-up posi- 
 tion when feigning death; c, Moth 
 with wings folded. (Somewhat en- 
 larged.) 
 
INSECTS 221 
 
 may be dropped and afterward eaten with the food 
 and thus start a disease. 
 
 Flies may be exterminated from any community 
 if all the people work together. It will be worth 
 while for you to aid in starting a fly campaign in your 
 district. There are several things that may be done. 
 First, it is absolutely necessary to get rid of all the 
 breeding places. Second, use traps of various kinds. 
 Place some of them out-of-doors, at some distance 
 from the house near barns and chicken yards. By 
 using attractive bait, and by keeping other sources 
 of food such as scraps and all garbage cans covered, 
 you can succeed in catching every fly in the district. 
 Some of the best baits are milk, banana, and bran 
 mixed with sweetened water. Traps should be set 
 early in the season when the flies are awaking from 
 their winter sleep. In this way they will be prevented 
 from depositing their eggs and starting a new gen- 
 eration. You may make traps for yourself with little 
 cost. 
 
 LIST OF COMMON PESTS 
 
 Garden pests not discussed above. Larvae of black, swallow-tail 
 butterfly found on parsley and parsnips. Usually they may be con- 
 sidered neutral since they are not abundant enough to do much 
 harm. The Colorado potato beetle. The corn ear- worm which feeds 
 upon the ears of sweet corn, also upon field corn. Strawberry leaf- 
 roller. White grubs, which are larvae of May beetles and feed upon 
 the roots of numerous garden plants. Cut-worms, which feed upon 
 stems of young plants, cabbages, corn, etc., cutting them off close 
 
222 
 
 STUDIES IN SCIENCE 
 
 to the ground. The adult is a moth. Currant and gooseberry-worm. 
 The adult is a sawfly. 
 
 Field pests. Grasshoppers feed upon grasses, clovers and corn. 
 Army- worms upon oats, wheat and corn. Corn-root aphis. Corn- 
 root worm. White grubs upon roots of grass and corn. Chinch- 
 bugs upon wheat, oats and corn. Hessian-fly upon wheat. Cut- 
 worms. Wire worms, which feed upon corn. Cotton-boll worm and 
 cotton-weevil, which feed upon cotton. 
 
 Fruit tree pests. Coddling-moth, canker-worm, woolly aphid, San 
 Jose scale, scurvy scale, apple-tree borers, tent caterpillars, the 
 peach-tree borer, plum curculio, bark beetles. 
 
 Enemies of forest or shade trees. Fall web-worm, catalpa sphinx, 
 elm leaf -beetle, aphids, leaf rollers, bag- worms, bark beetles, scurvy 
 scale, oyster- shell scale, San Jose scale, white marked Tussock-moth, 
 gypsy-moth, brown tail moth, elm sawfly, bronze birch borer, locust 
 borer. 
 
 Household pests. Cockroaches, ants, clothes-moths, flour-worms, 
 mosquitoes, stable-fly, house-fly, carpet-beetles, corn-meal moth. 
 
 Fig. 46. The celery caterpilar (Papilio Polyxenes). a, Larva from 
 side; b, Larva showing head with odoriferous appendages; c, Male 
 butterfly; d, Outline of egg; e, Young larva; f, Chrysalis. (All about 
 natural size except d, which is much larger.) 
 
 Insects with biting mouths may be controlled by 
 poisons placed upon the plants upon which they feed. 
 
INSECTS 223 
 
 Insects with piercing, sucking mouths cannot be 
 destroyed in this way since they feed from the inside 
 of the leaf or stem. They may be controlled by spray- 
 ing with insecticides that kill them by coming in 
 contact with their bodies. Those most effective are 
 kerosene emulsion, kerosene and water, whale-oil soap, 
 lime-sulphur mixture, and Black Leaf No. 40. 
 
 Recipe for poison sprays. Arsenate of lead is large- 
 ly taking the place of other poisons for biting mouthed 
 insects. It may be bought in the form of a paste 
 ready to dilute. Directions for mixing are on the 
 package. One pound of the poison may be mixed 
 with about sixteen gallons of water. Paris Green has 
 been a favorite spray for biting insects for years. 
 The standard formula for the mixture is : 
 
 4 ounces of Paris Green 
 V-2 pound of lime slaked 
 50 gallons of water 
 (Many people use it without the lime.) 
 
 Slug shot is a powder that contains poisonous mix- 
 tures It is sifted upon the plants and for small 
 gardens is quite effective. 
 
 Lime-sulphur like arsenate of lead may be bought 
 in packages ready to dilute. It is excellent for aphids 
 and scale insects. It is effective also in destroying 
 certain fungous diseases as blight. 
 
224 STUDIES IN SCIENCE 
 
 BENEFICIAL INSECTS 
 
 You must not think that all insects are pests. Many 
 of them are real benefactors. You already know 
 something of the value of bees in making honey and 
 in carrying pollen from one flower to another. To 
 some extent this is true of moths and certain wasps. 
 You know, too, the value of silk worms in producing 
 the silk of the world. There are other insects that 
 benefit us in quite a different manner, that is, by 
 destroying some of the insect pests. 
 
 Ladybird beetles. Ladybird beetles or ladybugs 
 are among the most beneficial insects. Look on any 
 plants infested with aphids and you will be almost 
 certain to find ladybugs both in the adult and larva 
 stages. Capture a few of the adults and place them 
 in a glass with some leaves on which are a number 
 of aphids. Watch to see what they do. Examine a 
 ladybird closely and decide why it is more correct to 
 call it a beetle than a bug. What kind of wings 
 has it? If you find any of the young, or larvae, 
 place them also in the glass and feed them on aphids. 
 After a few days they will pass into the pupa stage. 
 Note how they fasten themselves to a leaf or a stem. 
 Keep the pupa, and in a week or ten days the grown- 
 up beetle will appear. 
 
 There are a number of different species of lady- 
 
INSECTS 225 
 
 birds that are common everywhere. Most of them are 
 brightly colored, either red or yellow with black 
 spots. All of them pass the winter in the adult stage. 
 Often you will find them congregated in great num- 
 bers under a shrub or hedge during the winter months. 
 
 Ladybirds and their young not only eat aphids but 
 eggs and larvae of potato beetles and many other 
 injurious insects. They aid more than we can esti- 
 mate in keeping pests in check. In California they 
 are especially helpful in destroying scale insects that 
 feed upon orange and lemon trees. 
 
 Braconids and Ichneumons. When you studied 
 cabbage worms perhaps you found that some of them, 
 instead of pupating, died and had clinging to their 
 bodies a cluster of yellow cocoons. Each of these 
 cocoons had in it a small pupa. If you should place 
 the pupa in a glass with a cover over it, in the course 
 of about two weeks you would find the glass full of 
 small insects not larger than gnats, which had 
 emerged from the cocoons. They are the adult insects 
 and are called braconids. 
 
 If you could go back through the life history of 
 this insect, this is what you would find. Some time 
 during the summer the adult braconids deposit their 
 eggs under the skin of the cabbage-worm. Each egg 
 hatches into a small larva which feeds upon the fluids 
 in the body of its host. When it is ready to change 
 
226 STUDIES IN SCIENCE 
 
 to a pupa, it breaks through the skin of the worm 
 and spins its cocoon within which it changes to 
 a pupa. Usually the entire number within the worm 
 come forth at the same time killing it instantly. 
 
 The braconids destroy hundreds of cabbage worms 
 every year. If you look closely at one of the adults, 
 you will see that it has two pairs of membranous 
 wings and that its body is somewhat wasplike. In 
 fact, the braconids belong to the same group of in- 
 sects as the bees and wasps. 
 
 Sometimes you find tomato-worms or grapevine 
 sphinx larvae almost covered with white cocoons. 
 These belong to another species of braconids that live 
 in the bodies of these insects. A tomato-worm infested 
 with braconids, while it may not be killed outright 
 as in the case of the cabbage-worm, never lives to 
 become an adult moth. In some localities the braco- 
 nids keep the tomato-worms in check to such a degree 
 that no other remedy is needed. 
 
 You may find among aphids some dead ones that 
 have hard, swollen bodies. Some of them have a small 
 round lid cut in one side. These aphids have been 
 killed by still another species of braconid. The little 
 creature remains inside the aphid while it passes 
 through its entire life history. When grown up it 
 cuts a hole in the side of the body and comes forth. 
 Braconids are called parasites because they live and 
 
INSECTS 227 
 
 feed in the bodies of other insects. The insects in 
 which they live are called hosts. 
 
 Another group of parasites is known as ichneumons. 
 These are somewhat larger than braconids. Certain 
 ichneumons destroy hundreds of Tussock-moths w r hich 
 are so destructive to our shade trees. Others destroy 
 tent caterpillars that feed upon our apple trees, and 
 a few destroy the gypsy-moth, which is one of the 
 worst tree foes we have. 
 
 There are a number of other beneficial insects that 
 you will want to get acquainted with as soon as pos- 
 sible. Among them are: 1. The larva of the lace- 
 wing fly, called the aphis-lion because it devours so 
 many aphids. 2. Dragon-flies which feed upon mos- 
 quitoes and gnats. 3. Tiger-beetles which kill off 
 ants and some other ground insects. 4. Several spe- 
 cies of ground bettles that feed upon caterpillars; 
 chief among these is the beautiful green and blue 
 searcher which destroys the corn-ear worm. 5. Many 
 of the water beetles kill off great numbers of mos- 
 quito larvae. 6. The praying mantis kills weevils, 
 cottonboll worm, and other caterpillars. 
 
CHAPTER XIV 
 
 FUNGI 
 
 Material. Mushrooms, toadstools, puffballs, bracket 
 fungi, mold, smut and rust on wheat, oats, and corn. 
 Fungi is the name of a large group of plants in- 
 cluding mushrooms, toadstools, molds and many fung- 
 ous growths found on plants and animals. 
 
 Mushrooms or toad- 
 stools. Find some 
 mushrooms or toad- 
 stools. Where are 
 they growing! If 
 there are a number, 
 look for different sizes 
 or stages of develop- 
 ment. What is the 
 condition as to mois- 
 ture of the soil or 
 other substance upon 
 which they are found! 
 Collect some for indoor study. Try to get a little 
 of the substance upon which they are growing. 
 Examine one of the mushrooms. How many dis- 
 
 228 
 
 
 Fig. 47. A common mushroom: A, 
 The mycelium; B, The stem or stipe; 
 C, The pileus; D, The gills which 
 bear the spores; E, The young stage 
 of a mushroom. 
 
FUNGI 229 
 
 tinct parts has it? Look very closely at the 
 soil to determine whether a part of the plant is 
 in this. (See Fig. 47 for the names of the parts.) 
 What do you find on the under side of the cap or 
 pileus! The leaf like bodies are called gills. To 
 determine the use of the gills cut the stipe out close 
 to the pileus. Lay the pileus, gills downward, on a 
 sheet of white paper. Place it where it will not be 
 disturbed. After twenty-four hours carefully lift 
 the pileus. What do you find on the paper? The 
 powder is composed of spores. These are the repro- 
 ductive bodies. They produce new mushroom plants 
 just as seeds produce corn or wheat. What is the 
 color of the spores? What does the print indicate 
 as to where the spores are borne? 
 
 Compare the young stages of the mushrooms with 
 the older ones noting differences. If the weather is 
 warm, watch their development. How rapidly do they 
 grow? How long do they remain in good condition 
 after they are fully grown? 
 
 Look for different kinds of mushrooms and toad- 
 stools. Compare as to shape, size, and color. Make 
 spore prints and note differences in size and color of 
 spores. 
 
 Puff balls. Where do you find puffballs growing? 
 How large are they? Is the mycelium more or less 
 easily found than that of mushrooms? Cut one in 
 
230 STUDIES IN SCIENCE 
 
 two and describe the inside. How does a mature one 
 differ from a young one? If you find no mature ones, 
 lay some aside until they dry. Are there many or 
 few spores! 
 
 Discussion. From your observation you have prob- 
 ably concluded that mushrooms, toadstools and puff- 
 balls are found in places where there is plenty of 
 moisture and some sort of decaying vegetation. The 
 fact is that these plants and all other fungi are 
 dependent upon seed plants for their food. Since they 
 do not have the green coloring matter found in leaves, 
 they cannot manufacture their own food. This is 
 why you find them growing among decaying leaves, 
 stumps or logs. Some of them are found in meadows 
 which are rich in decaying grasses. Some are found 
 in the rich, decaying matter around barns. 
 
 The thread-like mycelium penetrates the soil or 
 other substance and procures the food. The part that 
 is above ground grows up for the purpose of produc- 
 ing the spores. It is called the fruiting body. The 
 spores of mushrooms and toadstools are produced on 
 the free edge of each gill ; those of puffballs are borne 
 inside the ball. The mycelium may grow for weeks or 
 months before it sends up the fruiting body. During 
 dry or cold weather it may remain alive but inactive 
 for months; then when the proper conditions come, 
 it grows rapidly and sends up the spore bearing body. 
 
FUNGI 231 
 
 From this you can readily see that the spores when 
 they germinate and grow produce the mycelium. 
 
 Mushrooms are of interest because they furnish 
 human food. Some are edible; others are poisonous. 
 The poisonous ones are frequently called toadstools. 
 Many people raise edible mushrooms for market and 
 for canning. Others collect them for table use from 
 the woods and meadows. These people have learned 
 to recognize certain edible species. If you wish to 
 collect mushrooms for food, the best plan is to take 
 a specimen to some person in the neighborhood who 
 knows which ones are edible. There are some gen- 
 eral characteristics that will help you to distinguish 
 the edible from the poisonous kinds. 
 
 1. Some of the most deadly ones have the lower 
 part of the stem surrounded by a cup-like membrane. 
 So you should always dig down far enough to be 
 sure that no cup is present. 
 
 2. Avoid mushrooms covered with scales. 
 
 3. Poisonous species are likely to have white 
 spores; edible ones dark spores. 
 
 4. Avoid those with milky juice or with shiny 
 caps. 
 
 5. Do not eat them after the meat has turned dark. 
 All puffballs are edible although the flavor is not 
 
 always as delicious as that of most mushrooms. All 
 the precaution that is necessary in collecting these 
 
232 STUDIES IN SCIENCE 
 
 for food is to be sure that they are puff balls and not 
 young stages of poisonous mushrooms. 
 
 Bracket fungi. Look on trees, stumps or logs for 
 bracket fungi. What kind of trees do you find them 
 on? On what part are they growing? Are the trees 
 alive or dead? 
 
 Examine one of the brackets. Compare the upper 
 and under surfaces. Look for layers of growth. On 
 which surface do they show more distinctly? Exam- 
 ine the lower surface with a lens and describe it. Cut 
 a section through the fungus and determine how 
 far you can trace the small tubes. Cut off a bit of 
 bark with some of the younger specimens attached 
 and look for the mycelium, a mass of white threads at 
 the base of the fungus. If the tree is dead, slice off 
 a piece of bark to determine whether or not the 
 mycelium penetrates the wood. 
 
 Make a collection of bracket fungi. They may be 
 dried and mounted by means of pins in shallow paste- 
 board boxes. 
 
 Discussion. The spores of bracket fungi are borne 
 in the tiny tubes whose openings you found on the 
 lower surface. The spores drop out, are carried by 
 the wind, settle upon trees, stumps, etc., where they 
 germinate and grow. The mycelium penetrates the 
 wood feeding upon it. Usually these fungi are found 
 upon dead trees, logs and stumps which in time they, 
 
FUNGI 233 
 
 with the other fungi, reduce to mere vegetable mold 
 in the soil. 
 
 Some species, however, are found feeding upon liv- 
 ing trees. Occasionally they kill the entire tree; but 
 usually they only injure some of the branches. How- 
 ever, the spores cannot find access to a tree unless 
 there are wounds in the bark. If a tree receives an 
 injury in any way, the wound should be cared for at 
 once. A coat of paint is excellent for this. 
 
 Mold. Mold is a fungus that is frequently found 
 in our homes. About a week before you are ready 
 to begin this study, moisten a piece of stale bread, 
 put it on a piece of pasteboard, and turn a tumbler 
 over it to prevent it from drying. Keep it in a warm 
 place but not in a strong light, and look at it occa- 
 sionally. When there is a good crop of mold, examine 
 it carefully. What color or colors do you find? How 
 many distinct parts are there? What do you think 
 the threads are? The little white or black balls? 
 To what extent do the threads, or mycelium, penetrate 
 the bread? Put a piece of white cloth over the upper 
 end of your lead pencil and rub over the black balls. 
 What happens ? What is the black dust on the cloth ? 
 
 : '.\ ' '' -* t ' ? ! i::-i* A- . ; ' ; j . s ' ' -* "tf^ \l~:''..-~~ f ~. to .l":.;-il. ,'- ''_-.'..: ""'?' 
 
 GROWTH OF MOLD. 
 
 Experiments. 1. Moisten a piece of bread and with 
 a small splinter or the end of a match transfer some 
 
234 STUDIES IN SCIENCE 
 
 of the dust or spores to the bread. Plant them in 
 rows. Turn a tumbler over the bread and keep in 
 a warm, dark place. Examine every day. How soon 
 do you find mold growing from the spores? How 
 long before spore cases, the black balls, appear? 
 
 2. Moisten a piece of bread. Collect some dust 
 from furniture or corners of the room. Place this in 
 rows on the bread. Cover with a tumbler and watch 
 for results. 
 
 3. Moisten two pieces of bread and plant spores 
 on them. Place one in a dark, warm place; the other 
 in a warm, sunny window. 
 
 4. Get a moldy orange or lemon. What color are 
 the spores? Eub a pin point over the spores and then 
 insert the pin into a good orange. Sterilize another 
 pin by passing it through a flame. Insert this in 
 another part of the orange. Eub some of the spores 
 on a small spot on the skin of the orange. Place the 
 orange in a covered jar or dish so it will not be dis- 
 turbed. Watch for results. 
 
 From your experiments answer these questions: 
 What starts a growth of mold? What conditions aid 
 the growth? W^hat may be done to prevent mold? 
 
 Make a list of everything about the home that is 
 likely to be affected with mold. How many different 
 kinds of mold have you seen, judging from the color 
 of the spores? 
 
FUNGI 235 
 
 Discussion. Several different species of mold may 
 be found about your home. One of the most common 
 is bread mold, which has black spore cases and is 
 sometimes called black mold. It produces a fluffy 
 white mass of mycelium. Green mold is another 
 common kind. The mycelium is composed of very 
 fine white threads. You saw some of these around the 
 pin in the orange before the green spores appeared. 
 Sometimes you find on fruit a very white mold with a 
 compact mass of threads and white spores. 
 
 The mold spores are so small that one by itself 
 is not visible to the naked eye. They float about in 
 the air and settle down upon food, furniture and 
 clothing, forming a part of the dust. If they have 
 moisture, something to feed upon, and the tempera- 
 ture is not too cold, they grow rapidly, producing first 
 the mycelium and then the spores. 
 
 The spores may be killed by boiling water. You 
 found also that they do not thrive in strong sun- 
 light. Sterilizing cans, bread-jars, cake-boxes, etc., 
 will prevent mold from growing. 
 
 Smuts. Look at a head of oats that has smut on it. 
 Compare with a good head. Shake the smut-head 
 gently over a sheet of white paper. What fall off? 
 What other parts of the fungus must be present in 
 the oats! How do you account for the fact that an 
 oat plant with smut is shorter and smaller in every 
 
236 STUDIES IN SCIENCE 
 
 way than a healthy plant? How does the smut get 
 started on the oats? 
 
 Study a head of wheat that has smut on it just 
 as you did the oats. 
 
 What parts of corn are affected by smut? To what 
 extent does it destroy an ear? Break up a smutted 
 ear and look for mycelium as well as for spores. 
 
 Discussion. A fungus like smut that grows upon 
 living plants is called a parasite. All the smuts have 
 mycelium that penetrate the stems of the plants and 
 feed upon their juices. That is why smutted plants 
 are always dwarfed. The dust that you find is, of 
 course, spores. These are widely scattered in har- 
 vesting and threshing of the grain. 
 
 The life history of oat-smut is interesting. If you 
 sow oat seeds that have smut spores on them, this is 
 what happens : The spores germinate and grow soon 
 after the oat plant begins its growth. The threads of 
 the mycelium penetrate the young oat stem feeding 
 upon its sap. As the oat plant grows the mycelium 
 grows also, sending out many branches <ill through 
 the stem. When the oats begin to head out, the 
 mycelium grows into all parts of the head, and now it 
 is ready to form its spores. Some of the mycelium 
 threads penetrate the glumes (outer covering of the 
 grain), and come to the outside to form their spore 
 cases. Some form inside. Usually every grain or 
 
FUNGI 237 
 
 what would have been a grain is filled with spores. 
 
 It is an easy matter to prevent oat-smut. The smut 
 spores can be killed before the oats are planted. 
 The following recipe is used by many farmers: Put 
 one pint of forty per cent formaldehyde, sold under 
 the name formalin, into thirty-six gallons of water. 
 This is sufficient to treat forty bushels of oats. Put 
 the oats into gunny-sacks, dip them into the solu- 
 tion, leaving them from ten to fifteen minutes. Then 
 spread out on a floor to dry. Some farmers place the 
 oats on a floor and sprinkle them with the solution, 
 turning them over with a shovel so that every grain 
 is moistened. Oat-smut often attacks fifteen per cent 
 of the plants, which means a loss of fifteen per cent of 
 the crop, often all of the profit on the crop. 
 
 The history of stinking smut on wheat is practically 
 the same as that of oat-smut and it may be prevented 
 in the same way. 
 
 Corn-smut spores live over winter in the soil of 
 the fields or in piles of trash, especially stable manure, 
 near the fields. In the spring some of them are blown 
 around, alighting upon the young corn plant. Here 
 they grow and produce spores which blow to other 
 parts of the plant. Some of these attack the grow- 
 ing ears. To prevent corn-smut care must be taken 
 not to leave in the fields material in which the spores 
 can spend the winter. Another plan is to go through 
 
238 STUDIES IN SCIENCE 
 
 the field, cut out the affected stalks, and burn them. 
 There are a number of other fungous diseases. 
 Some of the most familiar ones are: 1. Potato-scab, 
 which may be prevented by the same treatment as 
 oat-smut. 2. Peach-rot, which attacks the half-ripe 
 peach. This may be helped by burning all the dried- 
 up peaches that are left on the trees and all the trash 
 that collects under the trees. 3. Potato-blight, which 
 may be prevented by spraying with Bordeaux mix- 
 ture. 4. Tomato-blight should receive the same treat- 
 ment as that of the potato. In both cases the spray- 
 ing should be done early, before the blight has made 
 any headway. 
 
CHAPTER XV 
 
 YEAST AND BACTERIA 
 
 Material. Yeast-cakes either dry or compressed, 
 sugar, salt, flour, several tumblers or wide mouth 
 bottles. 
 
 Experiments. What is yeast? Examine a yeast- 
 cake either dry or compressed. Of what does it seem 
 to be made! If you have a dry cake, break off a 
 piece about one inch square and crumble it into 2% 
 tablespoonsful of warm water at about 80 F. Do 
 not have it too warm. Number six tumblers, wide 
 mouth bottles or test tubes. 
 
 (a) Into numbers 1, 2 and 3 place % teaspoonful 
 of flour and Vi teaspoonful each of sugar and salt. 
 Mix them together and stir in two tablespoonsful of 
 warm water. Into this mixture stir one teaspoonful 
 of the dissolved yeast or a email piece of compressed 
 yeast. 
 
 (b) Into number 4 put the same ingredients as in 
 1 and 2 but omit the salt. 
 
 (c) In number 5 omit the sugar. . . 
 
 (d) In number 6 use nothing but water and the 
 3'east solution. 
 
 239 
 
240 STUDIES IN SCIENCE 
 
 Place tumblers numbered 1, 4, 5 and 6 in a warm 
 temperature, between 80 or 90 F., and allow them 
 to stand several hours or over night. 
 
 Place number 2 in a cool temperature, a refriger- 
 ator, or in a pan of very cold water and set out-of- 
 doors. 
 
 Heat number 3 to a high temperature by putting it 
 in a pan of boiling water, or steaming in a double 
 1 toiler for half an hour. 
 
 After a number of hours carefully compare the 
 different liquids, describe what you find and state 
 any conclusions you may derive. How does number 
 1 differ from number 21 From number 3? In which 
 has the greater change taken place, in number 4 or 
 5? Why do you think number 6 shows less change 
 than the others which were in the warm temperature? 
 
 Make a list of the conditions that brought about 
 the most noticeable results. 
 
 Making bread. Mix enough flour with the liquid 
 of number 1 to make a stiff batter and allow it to 
 stand in a warm temperature for an hour or two. 
 What change takes place? Now put in a half cup 
 of warm water and enough flour to make a stiff 
 dough. When thoroughly kneaded place it in a glass. 
 Measure the height to which it rises. Set in a warm 
 place and in an hour measure it again. How do you 
 account for the difference? If you wish to complete 
 
YEAST AND BACTERIA 241 
 
 the bread making process, knead the dough again, 
 place it in a patty pan and let it rise once more. 
 Then bake it in a hot oven. How do you account 
 for the pores or holes that you find in the bread! 
 
 Explanation. Your experiments show that there 
 is something in the yeast cakes that is affected by 
 outside conditions. You found that the liquids in 
 tumblers numbers 1, 4 and 5 were cloudy or turbid, 
 while in numbers 2 and 3 the solid material had set- 
 tled to the bottom and the liquid was clear. This 
 shows that something took place in the warm tem- 
 perature that did not occur in the very cold or hot 
 temperatures. 
 
 Number 6 shows that the materials put into the 
 solution with the yeast influenced the changes that 
 took place. 
 
 While the compressed yeast-cake looked like a 
 mass of frothy starch and the dry one like a mass 
 of corn-meal and starch, each contained great num~ 
 bers of tiny plants known as yeast. A single yeast 
 plant is so small that you cannot see it without the 
 use of a powerful microscope. In fact, you would 
 have to place about 2,800 of them side by side to reach 
 an inch in length. One yeast plant is an oval, color- 
 less cell. See Fig. 48. 
 
 In a dry yeast cake there are a great number of 
 these tiny plants alive but not growing. They are 
 
242 
 
 STUDIES IN SCIENCE 
 
 said to be in a resting stage. In the compressed 
 yeast the small plants are more active than in the 
 dry yeast. When you place the plants in the proper 
 conditions they at once begin to grow. These condi- 
 tions are moisture, food, and a warm temperature from 
 70 to 90 F. 
 
 The food that yeast plants live upon is some form 
 of sugar, fruit juices that contain sugar, or starch 
 that is converted into sugar. Flour contains sugar. 
 
 The small yeast 
 plant when it begins to 
 grow multiplies rapid- 
 ly by a process known 
 as budding. On the 
 side of the cell a small 
 swelling, called a bud, 
 appears. This grows 
 larger until it is about 
 the size of the original 
 cell and similar in appearance. Then a second bud 
 appears, sometimes on the first cell, sometimes on the 
 second, then another and another till there is a chain 
 of cells making an irregular mass. Fig. 48. 
 
 As the plants feed upon the sugar they change it 
 into two new substances, alcohol and carbon dioxide, 
 C0 2 . The bubbles that you found in the liquid and 
 batter were C0 2 . It is this gas that collects in bub- 
 
 Fig. 48. Yeast plants. A, A 
 single plant; B, A plant from which 
 a bud is beginning to grow; C, A 
 chain of plants showing how they 
 grow by budding. 
 
YEAST AND BACTERIA 243 
 
 bles throughout the dough and makes it swell or rise. 
 When you put the bread into the hot oven the C0 2 
 expands with the heat and gradually passes out into 
 the air leaving the bread very light and porous. The 
 alcohol also changes to vapor and passes into the air. 
 Number 2 did not show any growth of yeast because 
 the temperature was too low for the growth to take 
 place. Heating number 3 killed the yeast plants so 
 there was no growth. Number 6 did not grow because 
 of lack of food. 
 
 BACTERIA. 
 
 Material. Some fresh milk; a small piece of fresh 
 lean beef; a potato; a few small vials; several tumb- 
 lers and wide mouth bottles or test tubes; a double 
 boiler or kettle; a package of sterilized cotton. 
 
 Experiment. To determine why milk sours. 1. 
 Place one of the wide mouth bottles on its side in a 
 kettle of warm water and heat the water to the boiling- 
 point. With a fork turn the bottle over and over 
 in the water for about ten minutes. Take it out 
 and stand it inverted on a clean table until it cools. 
 Fill it half full of fresh milk, close the top with cot- 
 ton and set it aside in the schoolroom, or in the 
 kitchen if the experiment is tried at home. 
 
 2. Into another bottle place a small amount of 
 dust gathered from some place about the room. Fill 
 
244 STUDIES IN SCIENCE 
 
 the bottle half full of milk and stand it beside bottle 
 number 1. 
 
 3. Wash two bottles, fill each half full of milk, 
 plug with cotton, (a) Place one in a warm tem- 
 perature, near the stove or register, (b) Put the 
 other in a very cool place. If you have no refrig- 
 erator, place it in a pan of very cold water and set 
 the pan out-of-doors on the north side of the house. 
 
 4. Sterilize a bottle as in experiment 1. Fill it 
 half full of fresh milk and stir into it a half teaspoon- 
 ful of very sour milk. Place it beside bottles num- 
 bers 1 and 2. 
 
 5. Sterilize a bottle as in number 1. Fill it half 
 full of milk and set it in a double boiler. Keep the 
 water boiling for about twenty minutes. Remove the 
 bottle and cool it as quickly as possible. Plug with 
 cotton and place with numbers 1 and 2. 
 
 At the expiration of ten or twelve hours examine 
 the milk in all the bottles to determine whether or 
 not any changes have taken place. Examine again 
 after twenty-four hours or when definite changes have 
 occurred. In which bottle does the milk sour first? 
 In which does it remain sweet longest? What is the 
 effect of sterilization? Of a warm temperature? A 
 cool temperature? Why does milk sour? 
 
 Keep bottles number 2 and (a) of Experiment 3 in 
 a warm place for a number of days. Does the odor or 
 
YEAST AND BACTERIA 245 
 
 color indicate that anything besides souring is taking 
 place? 
 
 Explanation. The souring of milk is due to small 
 one-celled plants called bacteria. If you wish to 
 speak about one of them you call it a bacterium. 
 They are very much smaller than yeast plants. Like 
 yeast, however, they grow and multiply very rapidly 
 when proper conditions are present. They multiply 
 by cell division; that is, one cell divides into two. 
 These grow and in a short time each divides again. 
 This continues until in a few hours there may be 
 thousands of new cells from the one individual. 
 
 Your experiments have enabled you to determine 
 for yourself what the proper conditions for growth 
 are. You found that the milk in the cool temperature 
 kept sweet much longer than that in the warm place. 
 Bacteria grow and multiply rapidly in a warm tem- 
 perature. They feed upon the sugar in the milk 
 changing it into an acid. Bacteria that sour milk 
 are not harmful to man. Sour milk is a wholesome 
 food; but usually we wish to keep milk sweet for 
 certain purposes, and for that reason we keep it cool 
 to prevent the bacteria from growing. By using care 
 with the utensils in which milk is kept we may reduce 
 the number of bacteria. Have you thought out why 
 the milk in bottles numbers 2 and 4 soured so quickly, 
 while that in numbers 1 and 5 remained sweet so 
 
246 STUDIES IN SCIENCE 
 
 long! By keeping number 1 in the boiling water you 
 killed all the bacteria that it contained, while in num- 
 ber 2 you increased the number of bacteria by put- 
 ting in the dust. In number 4 there were a great 
 number of bacteria in the sour milk. By heating the 
 milk in number 5 you killed most of the bacteria. 
 
 Your experiments then lead to the following con- 
 clusions : 
 
 1. Bacteria cause milk to sour. 
 
 2. The more bacteria there are present, the more 
 quickly milk sours. 
 
 3. Sterilizing the vessels in which milk is kept aids 
 in keeping it sweet. 
 
 4. A cool temperature retards the development 
 of the bacteria and keeps milk sweet longer. 
 
 5. Heating milk for a period of twenty or thirty 
 minutes kills most of the bacteria that it contains, 
 hence it remains sweet for a long period. 
 
 6. The bad odor of the milk in bottles numbers 
 2 and 3 (a) tells you that there were other bacteria 
 in this milk than those which caused it to sour. They 
 caused the milk to spoil or putrefy, and milk in this 
 condition is not only unwholesome but dangerous. If 
 you heat milk for two or three minutes you may kill 
 most of the bacteria that cause sourness, but leave 
 unharmed the ones that cause putrefaction. The milk 
 in this case may remain sweet for several days and 
 
YEAST AND BACTERIA 247 
 
 yet be unwholesome. To insure the death of all bac- 
 teria the milk should be heated to a temperature 
 of 145 F. to 167 F. and kept at this temperature 
 about half an hour. This is called pasteurizing milk. 
 Sterilized milk is heated to the boiling point, allowed 
 to cool, then heated again to the same temperature. 
 Some experiments with meat. 
 
 1. Cut a piece of fresh, lean beef into small bits 
 and put them into one of the test tubes or bottles. 
 Pour boiling water over them and then steam in a 
 double boiler for an hour. Plug the test tube with 
 cotton, cool as quickly as possible and set aside, 
 
 2. Put about the same number of pieces into 
 another bottle. Pour cold water over them. Leave 
 the bottle open and stand it beside number 1. 
 
 3. (a) Put a piece of the beef into another bottle 
 and place in a refrigerator or in any cool place, 
 (b) Put another piece into a bottle and leave in a 
 warm temperature. 
 
 Look at all of the bottles every day noting the 
 changes that take place. Which first shows evidence 
 of spoiling! Which keeps in a good condition long- 
 est? What conclusions do you come to as to why 
 meat spoils! 
 
 Explanation. From your study of milk you have 
 probably concluded the beef spoils because of bac- 
 teria. Boiling kills the bacteria; thus the beef in 
 
248 STUDIES IN SCIENCE 
 
 bottle number 1 kept in a good condition longer than 
 that in number 2. The piece of beef that was placed 
 in number 3 (b) without moisture kept fresh longer 
 than number 2 because bacteria must have moisture 
 in order to grow and develop. While there is some 
 moisture in the meat itself the greater amount in 
 number 2 made rapid growth possible. Number 3 
 (a) simply shows that the bacteria develop more 
 slowly in a cool temperature. 
 
 Some experiments with potatoes. Wash a potato 
 and boil until it is cooked through. Sterilize a knife 
 by holding it in a flame or boiling water a few minutes, 
 (a) Cool the potato, then cut off a slice about half 
 an inch thick, place on a saucer, turn a tumbler over 
 it, and place in a dark part of the room, (b) Cut 
 another slice and over this scatter a little dust col- 
 lected from the room. Cover this also with a tumbler 
 and place beside the first specimen, (c) Cut another 
 slice and let some one who has dirty fingers press 
 them into .the potato; treat as in (a) and (b). (d) 
 Prepare another slice exactly like (b), but after cover- 
 ing with the tumbler set in a sunny window, (e) On 
 another slice put some dust as in (b), then sprinkle 
 with water in which you have put a few drops of 
 formalin. Set beside (b). 
 
 Look at the specimens every day keeping a record 
 of what happens. 
 
YEAST AND BACTERIA 249 
 
 Explanation. You may find several different things 
 taking place on the potatoes. Some may have bright 
 red or yellow spots. These are masses of certain kinds 
 of bacteria that are growing and feeding upon the 
 potato. You may find that on some a growth of mold 
 has started. The greater and more rapid growth on 
 the potato of experiments (b) and (c) shows that dust 
 contains bacteria. The failure of the bacteria to grow 
 on the potato in the window and on the one with for- 
 malin proves that sunlight is a real enemy of bacteria 
 and that formalin kills them. 
 
 From your experiments and the explanation you 
 have learned something about a few of the bacteria 
 that are found around your home and school. There 
 are, however, many other kinds that you will learn 
 more about in high school and college. Just how many 
 different species of bacteria there are nobody knows, 
 but we do know that these little organisms are abund- 
 ant everywhere. They are in the air, the water, the 
 soil, in the dust that settles upon furniture and other 
 objects in the home, and in certain kinds of food, 
 notably butter, cheese and vinegar. 
 
 Most bacteria are perfectly harmless; some are real 
 friends. Among the most beneficial are those that 
 work in soil changing into soluble form the compounds 
 found there both in the broken -up rock and in the 
 humus so that they may be dissolved in the water 
 
250 
 
 STUDIES IN SCIENCE 
 
 and taken .into the root hairs. Other kinds of bac- 
 teria that we must consider our friends are those 
 that cause decay of all kinds of dead plants and 
 animals. 
 
 Bacteria are of three different forms: 1. Cocci, 
 which are spherical; 2. Bacilli, which are rod-like in 
 shape; 3. Spirilla, which are in the form of a spiral. 
 
 Bacteria and health. 
 Some bacteria are dead- 
 ly enemies because they 
 cause some of cur 
 most dangerous d i s - 
 eases, chief among 
 which are tuberculosis, 
 typhoid, diphtheria, 
 dysentery, pneumonia, 
 grippe, and colds. 
 
 We often speak of 
 bacteria that cause these 
 diseases as germs. When these germs are taken into 
 the human body they may in a short time begin to grow 
 and multiply. In the process of growth they produce 
 poisons known as toxins. It is these poisons that cause 
 fever and sickness. An important point to remember 
 is that none of these diseases start unless the germs 
 are in some way transmitted from a person who is ill 
 to one who is well. If people who have these diseases 
 
 Sx 
 
 Fig. 49. A group of various kinds 
 of bacteria. A, Coccus forms: B, 
 Spirillum forms ; C, Bacillus forms. 
 
YEAST AND BACTERIA 251 
 
 were careful not to allow any of the germs to be car- 
 ried from the sick room and distributed to other people, 
 all infectious and contagious diseases could within a 
 few years be exterminated. 
 
 Quarantine and disinfectants are means taken to 
 prevent the spread of diseases. As soon as the health 
 officer in any community knows of a case of a contag- 
 ious or infectious disease, and it should be reported to 
 him by the physician as soon as discovered, he at once 
 puts up a placard with the name of the disease. This 
 is the signal for everyone except the nurse and physi- 
 cian to stay out. People who are quarantined should 
 realize that while it is a misfortune it is no disgrace. 
 They should do everything in their power to keep 
 the quarantine. 
 
 Disinfectants are substances that are used to kill 
 bacteria that may escape from the sick room and infect 
 other people. Carbolic acid is one. This should be 
 made into a weak solution, which means about three 
 and one-half ounces of carbolic acid to a gallon of 
 water, or four teaspoonfuls to a pint. Clothes and 
 vessels used in a sick room should be washed with 
 this solution. The burning of sulphur candles in a 
 room is a fairly good disinfectant for most disease 
 germs. Of course, sulphur must be burned when there 
 is no one in the room, since human beings are poisoned 
 by the fumes. Formaldehyde is now used most 
 
252 STUDIES IN SCIENCE 
 
 commonly in disinfecting buildings or rooms. Special 
 directions are necessary if this work is done properly. 
 In many places school buildings are disinfected at 
 least once a month. Can you explain why? 
 
 Besides the use of disinfectants there are other ways 
 to prevent the spread of disease bacteria. One is 
 cleanliness; keeping the air we breathe and the food 
 we eat free from disease germs. This means care in 
 the home and school. It means as little dust as pos- 
 sible, the use of vacuum cleaners, of dustless dusters, 
 of rugs instead of carpets; in fact, everything that 
 keeps dust out of the air. Water heated to the boiling 
 point kills many germs. This should be used freely 
 in washing dishes and clothing. 
 
 One of your experiments suggests another method 
 of combating bacteria, that is by sunlight. Few kinds 
 of bacteria can live in the light of the sun. Clothing 
 and bedding should be exposed to the sun and air 
 occasionally to kill any germs that may be hiding in 
 them, and to keep them in a sanitary condition. 
 
 Fighting bacteria with good health. After all, one 
 of the strongest weapons with which to combat dis- 
 ease germs is good health and germ resisting power. 
 When germs are taken into the body the white cor- 
 puscles of the blood at once begin to destroy them. 
 If the corpuscles are numerous and the blood in good 
 condition, the corpuscles are likely to come off victor- 
 
YEAST AND BACTERIA 253 
 
 ions in their struggle with the germs. The corpuscles 
 are aided in this work by another substance in the 
 blood known as the germicidal substance. This attacks 
 the germs killing them before they can produce enough 
 toxin to cause sickness. The blood also produces an 
 anti-toxin which helps to destroy the toxin. Now if 
 your body is in a healthy condition all of these agents 
 work together and the result is that the bacteria are 
 destroyed without your having any evidence of their 
 presence in your body, or, if they succeed in causing 
 illness, the attack is likely to be a mild one. 
 
 Certain diseases are treated by putting into the 
 blood some of the anti-toxin of the disease so the blood 
 will set about making more of the germicidal sub- 
 stance and thus always have enough to prevent the 
 disease from getting a hold in the body. Typhoid 
 fever, diphtheria and smallpox are satisfactorily 
 treated in this manner. 
 
 People are not likely to take certain diseases such 
 as smallpox and measles a second time. This is because 
 the disease leaves enough of the germicidal substance 
 in the blood to kill off any germs of the disease that 
 may attack the body later. 
 
 Here are some simple rules to follow in combating 
 bacteria that cause human diseases: 
 
 1. Keep all rooms, especially sleeping rooms, wel] 
 ventilated. 
 
254 STUDIES IN SCIENCE 
 
 2. Keep window shades up to allow the sunlight 
 to enter rooms freely. 
 
 3. Avoid stirring up dust in living rooms, and 
 remove with an oiled or damp cloth any dust that 
 settles upon furniture and other objects. 
 
 4. Keep the body clean and pay particular atten- 
 tion to the hands and nails. 
 
 5. Do not form the habit of spitting in the street, 
 but help all you can to enforce ordinances against 
 spitting in public places. 
 
 6. Do not eat fruit that has been exposed to the 
 dust of the street without washing thoroughly. 
 
 7. In case of a typhoid fever epidemic boil drink- 
 ing water. 
 
 8. Keep up a constant warfare against flies and 
 mosquitoes till they are exterminated from your 
 community. 
 
 9. Keep your body in good health by following 
 the proper rules of eating, exercising, sleeping, and 
 avoiding stimulants such as tobacco and alcohol. 
 
 10. When you sneeze or cough be sure to cover 
 your nose and mouth with your handkerchief. This 
 precaution will keep your disease germs from spread- 
 ing to other people. 
 
CHAPTER XVI 
 
 PROPAGATING PLANTS BY CUTTINGS 
 
 Material. Geraniums, coleus, lantana, wandering 
 Jew, heliotrope, or any other plants that may be 
 started from cuttings or slips; a sharp knife; a pro- 
 pagating box and flower pots. 
 
 While many of our garden plants, both flowers and 
 vegetables, are grown from seeds, some are propa- 
 gated in other ways. Some familiar examples are 
 the growing of onions from bulbs, of potatoes from 
 tubers, of strawberries from runners. Make a list 
 of all the different methods of propagating plants 
 that you know with an example of each. 
 
 The propagating box. One of the first things to do 
 if you are planning to make cuttings is to prepare 
 a box in which to grow them. Any wooden box will 
 serve. If you grow them in the schoolroom or 
 at home, you will have better success if you make 
 one side of the box about two inches lower than the 
 other so that it will have a sloping top. Nail a nar- 
 row strip of wood just inside the box all the way 
 around so you may place a pane of glass over it. 
 Fill the box about two-thirds full of clean sand or 
 
 255 
 
256 STUDIES IN SCIENCE 
 
 other soil, moisten thoroughly, and the box is ready 
 for the cuttings. 
 
 You may make a box that will serve as a window- 
 box as well as for propagation. This should be made 
 the right length to fit the window in which you wish 
 to place it. It should be about eight inches deep 
 and from six to eight inches wide. Any kind of 
 lumber will serve, but cypress is the best since it 
 stands moisture better than other woods. Bore two 
 or three holes in the bottom for drainage and put 
 in first a layer of coarse material, cinders or pebbles, 
 then put in the soil. If the soil is rich, heavy, black 
 loam, a small amount of sand mixed with it will be 
 an advantage. If it is not very rich, humus, either 
 leaf mold or well rotted stable manure, will improve 
 it. A good soil mixture for potting or for window- 
 boxes is one-half loam, one-fourth sand and one- 
 fourth humus. 
 
 SOFT WOOD CUTTINGS 
 
 Cuttings. A common method employed in growing 
 certain plants is by the use of cuttings. You may use 
 different parts of plants to make cuttings. Some 
 begonias are propagated by leaf cuttings. You make 
 tuber cuttings when you plant potatoes. Most cut- 
 tings, however, are made from stems. 
 
 There are two kinds of stem cuttings, the soft or 
 
PROPAGATING PLANTS BY CUTTINGS 
 
 257 
 
 green wood, and the hardwood. A number of plants 
 grown in the garden and in the home are propagated 
 by softwood cuttings. Some of the best ones to use 
 for this purpose are coleus, sometimes called foliage 
 plants, salvia, geraniums, lantana, balsam, heliotrope, 
 tradescantia or wandering Jew. 
 
 Choose a fresh, thrifty looking branch of coleus 
 or other plant for your cutting. Look at it a mo 
 
 Fig. 50. a, Where the cut is made; b, How the cutting should look 
 
 when finished. 
 
 ment to determine how the leaves are arranged. 
 We call the place on the stem from which the leaves 
 grow a node. Use a sharp knife and make a clean 
 horizontal cut just below a node. (Fig. 50a shows how 
 this is done.) 
 
 Cut off the lower leaves and trim the ends from 
 the upper ones. Why is this done I You know that 
 leaves of plants constantly give out moisture. By 
 
258 STUDIES IN SCIENCE 
 
 thus reducing the leaf surface the cutting will not 
 lose so much moisture. Fig. 50b shows how the cut- 
 ting should look when finished. 
 
 With a wooden paddle or sharpened stick make a 
 drill in the sand or soil of your propagation box. 
 Place the cuttings in the drill about two inches apart. 
 With your fingers firm the moist soil closely around 
 them. Water the plants thoroughly and keep in a 
 dim light for two or three days. You may accom- 
 plish this by covering the box with a newspaper. 
 After two or three days give the plants plenty of 
 light and water when needed. They should from the 
 beginning be kept in a warm temperature. They need 
 air as well as light and water, so if you are growing 
 them in a glass covered box be sure to raise the 
 cover a few minutes every day for the purpose of 
 ventilation. 
 
 There is another way in which cuttings may be 
 grown that is very satisfactory for either school or 
 home. Place the usual pebbles or coarse materials 
 for drainage in the bottom of a large flower pot eight 
 or ten inches in diameter, and fill with soil leaving 
 a space in the middle. Plug up the hole of a small 
 pot three or four inches in diameter and set this 
 inside the large one. Fill the space between pots 
 with soil and place the cuttings here. Keep the small 
 pot filled with water. Coleus plants may not only be 
 
PROPAGATING PLANTS BY CUTTINGS 259 
 
 started in this way but they may be kept all winter 
 making a very pretty mass of foliage. 
 
 The callus and roots. What do you expect your 
 cuttings to do in the propagation box? The very best 
 way to answer this is to wait three or four weeks 
 until the cuttings are ready to be transplanted. Then 
 take one up and examine the cut surface. What has 
 taken place! The rounded portion at the end of the 
 stem where the cut has healed is called a callus. The 
 first thing the cutting does is to form a callus by lay- 
 ing down a new layer of cells over the cut surface. 
 After this it sends out roots. If a callus does not 
 form the cutting dies. Where have the roots ap- 
 peared! Compare different cuttings to determine 
 whether they sent out their roots with equal rapidity. 
 
 Transplanting. Now that the roots have developed 
 your cutting is ready to transplant. You may trans- 
 plant it into a window-box or flower pot. If you have 
 no pots, tin cans will serve equally well. Punch a few 
 holes in the bottom for drainage. Place a few peb- 
 bles or bits of broken pottery in the bottom of the 
 pot or can. Then fill it half full of soil using the 
 mixture suggested above. Place the cutting in the 
 center taking care to spread out the roots. Hold it in 
 place with your left hand while with your right hand 
 you fill the space around it with soil, firming it 
 closely about the plant. Do not fill the pot to the 
 
260 STUDIES IN SCIENCE 
 
 brim. Leave a space of at least three-fourths of an 
 inch. Water thoroughly and leave in a dim light 
 for two or three days. 
 
 Caring for the plants. After the plants are well 
 started, place them in a warm, well-lighted window; 
 a south window is best but they will do fairly well 
 with care in other windows. 
 
 The chief points to consider in caring for your 
 plants are: First, to see that they have the right 
 amount of water. It is better to give them a thorough 
 drenching two or three times a week rather than a 
 little sprinkle every day. When the soil looks dry 
 on top it is time to water. The temperature of the 
 water should not be lower than that of the room in 
 which the plants are kept. Besides water plants need 
 fresh air. This is easily supplied. Air that is fresh 
 enough for you to thrive in is all right for your 
 plants. You should be careful, however, when the 
 weather is severe not to allow cold air from an open 
 door or window to strike them'. During the very 
 cold weather ventilate from another room. 
 
 Plants also need certain mineral foods that are 
 obtained from the soil. If soil is well supplied with 
 humus, it is probably rich enough. If not, a fertilizer 
 may be used. The following recipe is recommended 
 by gardeners: Procure three ounces of nitrate of 
 soda, one ounce phosphate of soda, and two ounces 
 
PROPAGATING PLANTS BY CUTTINGS 261 
 
 of sulphur of potash. Pulverize and mix these mate- 
 rials thoroughly. When required for use put a level 
 tablespoonful into a gallon of hot water. When cold 
 use about a teacup full for pots five and six inches 
 in diameter and more or less in proportion to the 
 size of the pots. Do not apply oftener than once in 
 two weeks. Be careful not to allow the nitrate to 
 touch the foliage. 
 
 Value of cuttings. Why is it an advantage to 
 propagate plants by cuttings instead of seeds? One 
 advantage is that you get results much sooner. The 
 most important advantage, however, is that when 
 you use a cutting you are perfectly sure to get the 
 particular variety of plant from which the cutting 
 is made. You cannot always be certain of the exact 
 variety when seeds are used. In many cases seeds do 
 not hold true to variety. 
 
 Softwood cuttings may be made at any season. 
 House plants that have done well over winter may be 
 used to make cuttings in the early spring to trans- 
 plant later to the yard or garden. Late summer is 
 a good time to make cuttings for winter blooming. 
 
 HARD WOOD CUTTINGS 
 
 Material. Twigs or small branches from grape- 
 vines and shrubs of various kinds. 
 
262 STUDIES IN SCIENCE 
 
 Hardwood cuttings of shrubs or trees must be made 
 late in the fall or winter when the plants have stopped 
 their work and are inactive. They are sometimes 
 called dormant cuttings because they are made when 
 the plants are in a dormant or resting condition. 
 
 You may propagate grapes, currants and goose- 
 berries, as well as almost all of our ornamental shrubs, 
 by means of cuttings. 
 
 Grape cuttings. If you have access to a grape- 
 vine, go out and examine it. Find the stems that 
 have grown this season. How long are they? Take 
 some actual measurements. How do they differ from 
 the older portions of the stem? Find where the leaves 
 were attached. Where are the tendrils in relation to 
 the leaf scars'? Do grapevines depend wholly upon 
 tendrils for climbing? Describe the buds. Are they 
 opposite or alternate in arrangement? Where is the 
 bud situated with reference to the leaf scar? 
 
 Make the grape cutting from this season's growth. 
 Use care in making the cut. Place your knife on the 
 side of the stem opposite a bud and on a level with 
 the top of it. Now make a slanting cut downward 
 so that the knife will come out just below the bud. 
 You have thus made an oblique cut directly through 
 a node. Each cutting should have at least three 
 good buds. When you have made a number, tie them 
 together into a bundle. Nurserymen tie them in 
 
PROPAGATING PLANTS BY CUTTINGS 263 
 
 fifties and hundreds. Place them in a box of moist 
 sand or soil taking care that the lower end is well 
 covered with sand. Put the box in a cellar or other 
 cool place. It may be set out-of-doors , and covered 
 with straw or sand. If the box is kept in the cellar, 
 look at it occasionally during the winter to see that 
 the sand does not dry out. 
 
 Shrub cuttings. If you should like to have shrubs 
 on your home or school grounds and are willing to 
 wait a year or two, you can easily start them by the 
 use of cuttings. The following are easily propagated 
 in this way and are excellent shrubs for the home 
 grounds: Japanese barberry, common barberry, all 
 the bush honeysuckles, snowballs, high bush cran- 
 berry, hydrangeas, snowberry, and all the spireas. 
 
 Frequently in parks and home grounds these shrubs 
 are pruned during the early winter. Ask the owner 
 for some of the fresh branches and use them to make 
 cuttings. If no pruning is in progress, ask some one 
 who owns large shrubs to let you have a few young 
 branches. They may be taken from the thickest parts 
 without being missed. Use the same plan that is 
 suggested for grape cuttings. You will find that some 
 of the shrubs have many nodes and therefore the 
 buds are very close together, so in order to have your 
 cutting six or eight inches long it may have a large 
 number of buds. In that case it is a good thing to 
 
264 STUDIES IN SCIENCE 
 
 cut off the lower buds leaving two or three at the 
 top. Tie the shrub cuttings together and place them 
 as you did the grape cuttings in a cool, moist place 
 for the winter. 
 
 What do you expect your cuttings to do during 
 the winter? You must wait until spring to be sure 
 of the answer. Then if you look at your cuttings, 
 you will find that they have made a callus around 
 the margin of the cut. Probably some of them will 
 have already sent out roots. 
 
 Setting out the cuttings. Just as soon as the 
 ground in your garden can be worked in the spring 
 set out your cuttings. Dig a trench deep enough 
 so that when the cuttings are placed in it only the 
 topmost bud of each will stand above the surface of 
 the soil. Place them from eight to nine inches apart 
 and firm the soil well around them. During the 
 summer they should be kept free from weeds and 
 cultivated carefully. If the season is a very dry one 
 and they begin to show signs of wilting, they should 
 be watered. 
 
 The second spring or fall they will be ready to 
 transplant to their permanent places on your home 
 ground. 
 
CHAPTER XVII 
 
 FRUIT AND FRUIT TREES 
 
 Material. Fruit trees of the neighborhood; twigs 
 of apple and other trees; fruit of apple, pear, orange 
 and others. 
 
 Study. Make a list of fruit trees that grow in your 
 community. For 
 what purpose are 
 they grown! Which 
 species is most abun- 
 dant! Which next! 
 What fruits are on 
 the market that do 
 not grow in your 
 neighborhood! What 
 fruit trees do you 
 consider most impor- 
 tant the world over! 
 
 The apple. Examine an apple. What parts do you 
 find! What is the use of the skin! To answer this 
 remove the skin from an apple and then allow the 
 apple to stand on the table for several days. Why 
 is a thick skin of value when apples are to be shipped 
 
 265 
 
 Fig. 51. Section of an apple flower: 
 a, Beceptacle; b, One of the sepals; c, 
 One petal; d, Stamens; f, Upper part 
 of pistil; e, Ovary, the lower part of 
 the pistil. 
 
266 
 
 STUDIES IN SCIENCE 
 
 or kept a long time? Compare the skin of early and 
 late apples. Notice the shape of the apple where the 
 stem is attached. The hollow space around the stem 
 is called the cavity. Examine the opposite end and 
 describe what you see. The hollow portion here is 
 the basin. What do you find in the center of the 
 basin? What is this the remains off 
 
 ,C Cut an apple cross- 
 
 w i s e through the 
 middle. How many 
 distinct structures do 
 you find? What is 
 the shape of the core! 
 How many cells has 
 it? How many seeds 
 in a cell? Look for 
 the core line which 
 connects the points of 
 the star. Cut an- 
 other apple length- 
 wise .and look for the same structures. Trace the 
 core line from the cavity to the basin. In which 
 direction do the seeds point? What parts of the 
 flower produce each part of the fruit? Study Fig. 51. 
 An apple shows something of all parts of the flower 
 except the corolla. The stem of the apple is the stem 
 of the flower grown somewhat larger. In the basin 
 
 Fig. 52. Section of an apple showing 
 parts: a, Core line; b, Core with seed 
 cell and seed; c, Cavity; d, Basin; e, 
 Remains of calyx. 
 
FRUIT AND FRUIT TREES 267 
 
 are the dry remains of the sepals and often a few of 
 the withered stamens and styles. The core is the 
 ripened ovary with its five pointed cells which con- 
 tain the seeds. Around the core is the receptacle 
 which has become thick and juicy and constitutes the 
 part of the apple that is eaten. 
 
 History. There is no question that the apple is the 
 most important of all fruits. It is probably a native of 
 southwestern Asia. It has been cultivated from time 
 immemorial, probably long before the beginning of 
 written history. It is now grown in all countries 
 situated in temperate zones. While there is but one 
 species known as Pyrus mains, there are hundreds 
 of varieties, some of which are adapted to one kind 
 of soil and climate, others to different conditions. 
 
 Discussion. The apple tree does not grow very tall 
 but spreads out making a round crown. On young 
 trees the bark is quite smooth and the tree rather 
 symmetrical. After it reaches middle age, that is, 
 when it is from twenty to forty years of age, its 
 branches lengthen very slightly each year, the bark 
 becomes rough and shaggy, and the whole tree has a 
 gnarled appearance that makes it very picturesque. 
 
 Varieties of apples. Bring in for study specimens 
 of different varieties of apples. Compare them as to 
 shape, size and color. Compare two apples of the 
 same variety grown in different parts of the comma- 
 
268 STUDIES IN SCIENCE 
 
 nity. Group the apples into winter and fall varie- 
 ties. There are probably no summer apples left at 
 this time. What is the most striking difference 
 between the two groups? The fall apples are more 
 mellow; they are almost ripe. Winter apples are 
 mature but will ripen later in the season. Apples 
 are mature when the seeds are brown, but they are 
 not ripe till the pulp is soft, mellow and juicy. 
 
 Make lists of different varieties of apples, group- 
 ing them according to the time they mature, as 
 Summer apples: duchess, harvest, early June, yellow 
 transparent. Fall apples: Grime's golden, snow, 
 Jonathan, maiden blush, bellflower, wealthy. Winter 
 apples: northern spy, wine sap, gano, russet, willow 
 twig, salome, wolf river, stark, Ben Davis, baldwin, 
 greening, spitzbergen, Jeannet, pippin. 
 
 Picking, storing and marketing. Discuss methods 
 of picking and storing apples. The main rule to fol- 
 low in picking apples is not to bruise them or 
 break the skin. This means that they must be hand- 
 picked, not shaken from the tree. Determine whether 
 all the apples on one tree are equally large, well- 
 shaped, and brightly colored. Look for any that are 
 imperfect. Apples with warty knots have been 
 affected with a fungous disease. 
 
 Grade your apples by placing together the finest, 
 the next best, and so on. Firms who make a spe- 
 
FRUIT AND FRUIT TREES 269 
 
 cialty of selling apples have several grades. One 
 large city firm grades as follows: Extra fancy, in 
 which all the apples are perfect; Fancy, in which they 
 are nearly perfect; Choice, good fruit but not all 
 well-colored; Number two, fruit that is hand-picked 
 but varies in size and color; however, no apple less 
 than two and one-half inches in diameter is consid- 
 ered. Any apple smaller or less perfect than Number 
 two is called a cull. 
 
 In preparing apples for market some are packed in 
 barrels, others in boxes. When apples are properly 
 packed they lie in layers and there are no large 
 spaces left vacant. The apples fit close, but not close 
 enough to bruise each other. Fancy apples from 
 western orchards are often wrapped singly in tissue 
 paper just as oranges are. 
 
 In keeping apples in your home over winter three 
 conditions are essential: First, temperature; the 
 apples should be kept as cool as possible. A tem- 
 perature of from 36 to 40 is considered good. Sec- 
 ond, ventilation; they should be placed in a room 
 where there is plenty of fresh air. Third, moisture; 
 if the air is dry the apples will lose their freshness 
 by evaporation. In a fruit cellar with windows all of 
 these conditions are easily secured. Summer and 
 early fall apples may be canned or dried for future 
 use. 
 
270 
 
 STUDIES IN SCIENCE 
 
 Uses and distribution of apples. Make a list of 
 all the different ways that apples may be cooked and 
 served as food. Consult your geography for the 
 apple growing regions of the country. How impor- 
 tant is the apple growing industry in your own 
 state? 
 
 Other fruits. Make a comparative study of other 
 
 fruits noting resemblances 
 and differences. Which ones 
 are similar in structure to 
 the apple? Which differ 
 most widely? 
 
 The apple, quince, pear 
 and crabs resemble each 
 other in structure. Each 
 has the core formed from 
 the ovary and the thickened 
 receptacle which forms the 
 chief part of the fruit. 
 This kind of fruit is called 
 a pome. 
 
 The fruit of the peach, plum, cherry and apricot 
 is known as a drupe or stone fruit. In this the inner 
 wall of the ovary hardens into a nutlike covering 
 which encloses the seed. The outside layer thickens 
 making the fleshy part that is used for food. The 
 orange is a type of berry with a thick, leathery skin. 
 
 Fig. 53. econ o a 
 a, Core line; b, Seed cell and 
 seed; c, Cavity; d, Basin; e, 
 The withered remains of the 
 sepals or calyx. 
 
FRUIT AND FRUIT TREES 
 
 271 
 
 This tough covering is a great advantage to growers 
 of oranges since it is possible to ship the fruit 
 long distances. It is also such a perfect protection 
 against bacteria and mold spores that the fruit keeps 
 in good condition many weeks with little care. The 
 skin of apples and of other fruits is a protection 
 against germs that cause decay. It also prevents the 
 rapid evaporation cf the juices. 
 
 Fig. 54. Section of a peach, a type cf drupe or stone fruit. A 
 plum, showing resemblance to peach. 
 
 The peach. The peach, too, is a native of central or 
 south Asia, probably of Persia. The scientific name is 
 Persica. Peaches are not grown as universally as 
 apples, being less hardy. They require a rather 
 warm temperature. In most cold regions the trees 
 die during the winter, and even in regions where 
 the trees survive severe winters the fruit or flower 
 buds are frequently killed, so that in many places 
 
272 STUDIES IN SCIUNC1S 
 
 a crop of peaches is produced only once in two 
 or three years. The most northerly peach grow- 
 ing centers, Michigan, Maryland and Long Island, 
 have their climate tempered by nearness to large 
 bodies of water. Peaches are grown extensively in 
 warm climates, in some parts of Georgia and Texas 
 and in other southern states, as well as on the Pacific 
 coast. There are two chief groups of peaches, those 
 with white pulp and those with yellow. Some of the 
 common varieties are Yellow: Elberta, Crawford, 
 Hale, gold drop, Sincols and Fitzgerald. White: 
 Champion, Carmen, Greensborough, and Belle. 
 
 Fruit trees. Make a special study of your apple 
 orchards and other fruit trees. Find out if you can 
 how old the orchard is. Look carefully at the trees. 
 Are any of them broken? Are there any dead 
 branches or suckers? Select one tree for special 
 observation. How tall is it? You may estimate the 
 height of the tree by measuring your own height 
 upon the trunk, then estimating about the number of 
 times the tree is taller than you. How thick is the 
 trunk? What is the color of the bark? Is it rough 
 or smooth? What is the shape of the tree? Com- 
 pare young and old trees in regard to appearance. 
 If there are apples on the tree notice on what part 
 of the branches they are borne and how they are 
 attached to the twigs. 
 
FRUIT AND FRUIT TREES 273 
 
 Twigs. Look closely at a twig and make a list of 
 everything that you find. How do the new and old 
 parts differ? Where are the buds situated? How 
 many different kinds of buds are present? Determine 
 if possible which ones will produce the leaves and 
 which the flowers in the spring. 
 
 Compare the twigs of other fruit trees. On which 
 do you find bud clusters? How many in one cluster 
 on the peach? Plum? Cherry? 
 
 You find the twigs of the apple tree covered with 
 whitish fuzz with buds along the sides and at the 
 ends. These are all leaf buds. Here and there you 
 find a short spur-like twig with a bud at the end. 
 That is the flower bud that will produce the fruit 
 next year. If you have looked carefully at your apple 
 trees you find all the apples attached to spurs. 
 
 Propagation. How are apple, peach and all other 
 fruit trees propagated? Most people who have 
 orchards or fruit gardens buy young trees from a 
 nursery and transplant them. In most cases this is 
 probably the wisest thing to do. But if you are 
 willing to wait three or four years longer for your 
 apples and pears and two years for peaches, cherries 
 and plums, you can raise your trees from the 
 beginning. 
 
 Seeds and seedlings. To raise an apple tree the 
 first thing to do is to plant seeds. Any apple seeds 
 
274 STUDIES IN SCIENCE 
 
 will do, but most nursery men use those of a hardy, 
 wild apple found growing on the hillsides in certain 
 parts of France. 
 
 Plant the seeds in drills in the fall or early spring. 
 If planted in the spring moisten them and leave them 
 out over night that the frost may aid in breaking the 
 hard covering. When the seedlings come up, thin 
 them till they stand about three inches apart in the 
 row. Cultivate during the summer as you would 
 any garden plant. In the fall remove them from 
 the ground, cut off the stems leaving about eight 
 or nine inches attached to the roots. Tie them in 
 bundles and place in moist sand or moss in a cool 
 cellar. 
 
 Grafting. If the seeds you planted were from a 
 Jonathan or any other special variety of apple and 
 you allowed the seedlings to grow until they were 
 old enough to bear fruit, the apples probably would 
 not be Jonathans or any other variety that you 
 planted. They might be very good, but the proba- 
 bility is that they would be small, sour, inferior 
 apples. In order to obtain any desired variety graft- 
 ing is necessary. If you wish a Jonathan apple you 
 must graft on to the root of your seedling a stem or 
 bud taken from a Jonathan tree. The same is true, 
 of course, of any other variety that you desire. 
 
 The root or part on which the graft is placed is 
 
FRUIT AND FRUIT TREES 275 
 
 called the stock. The part that is grafted on is called 
 the scion. It is very essential to choose the scion 
 from a tree that bears well and that has excellent 
 fmit, for your grafted tree will inherit all the quali- 
 ties of the tree from which the graft is taken. You 
 may graft at any time during the winter or very early 
 spring. Nurserymen do most of their grafting in 
 January and February. 
 
 To make the graft, first cut the stems from the 
 seedling and trim all the branches from the root. 
 Now make a long diagonal cut near the upper part 
 of the root; this is your stock. Choose a scion of 
 about the same size. Make the same kind of cut. 
 Now make a slit on the cut surface of each and slip 
 them firmly together. See Fig. 55. 
 
 Use great care to see that the layer directly under 
 the bark of the scion meets the same layer of the 
 stock. This is essential because this layer, called the 
 cambium, is where new growth occurs; hence this is 
 the only place where stock and scion can grow 
 together. The next step is to wrap grafting thread 
 or raffia firmly around the graft. Some nurserymen 
 cover the wound with grafting wax. When you have 
 made a number of grafts tie them together and 
 return them to the moist sand in the cellar. Leave 
 them until the soil is in good condition to work in 
 the spring, then set them out in rows nine or ten 
 
276 
 
 STUDIES IN SCIENCE 
 
 inches apart and deep enough so that two or three 
 inches of the scion will be above the ground. The 
 scion grows fast to the stock and then grows upward 
 producing the little apple tree, while the root is all 
 that is left of the seedling. 
 
 When the little tree is well started it is a good 
 thing to remove some of the buds allowing only the 
 
 Fig. 55. Root tongue-grafting. A, The untrimmed root of the seed- 
 ling; B, Scion trimmed and ready to be inserted; C, Enlarged section 
 of A trimmed and slit ready to receive the scion; D, Scion inserted 
 in stock. 
 
 stronger ones to produce the tree. Nurserymen leave 
 the trees from two to three years in the nursery row, 
 then they are ready to be removed and set out in 
 
FRUIT AND FRUIT TREES 
 
 277 
 
 the orchard or fruit garden. The kind of grafting 
 just described is known as root tongue-grafting. 
 
 In some apple growing regions apples are propa- 
 gated by budding instead of grafting. Budding is 
 really a form of grafting in which a bud of the desired 
 variety is placed on the stock of the seedling. Pears 
 and quinces are propagated just as apples are. Some- 
 times if seedlings are scarce nurserymen make three 
 or four stocks from the same root, cutting it into 
 lengths of three or four inches. 
 
 Cleft grafting is used when 
 one wishes to graft onto a 
 young growing tree or a 
 branch of an old tree. The 
 stem is sawed off and is cleft 
 split across the center. 
 
 or 
 
 The scion, which is a one- 
 year old stem, is cut wedge- 
 shaped a little thicker on one 
 edge than the other. This is 
 inserted into the cleft with 
 the thicker edge outward, so 
 that the cambium meets the 
 same part of the stock. If 
 
 the stock is more than an inch thick two scions are 
 inserted, one in each side. The wounds are covered 
 with grafting wax. By means of this kind of grafting 
 
 A 8 
 
 Fig. 56. Cleft grafting. A, 
 The stock with two scions in- 
 serted; B, The same with 
 grafting wax; C, In place. 
 
278 STUDIES IN SCIENCE 
 
 one may change an undesirable variety into one more 
 desirable, or raise several different varieties of fruit 
 on the same tree. 
 
 How long will it be after the tree is set out in the 
 orchard before it will produce apples? Different 
 kinds of apples vary in this respect. Some produce 
 apples in six or eight years, others require ten to 
 twelve years. You see, then, that to make an apple 
 tree beginning with the seed requires one year before 
 it is ready to graft, two or three years in the nursery 
 row, and from six to ten years in the orcliard before 
 it bears fruit. How long will an apple tree continue 
 to bear fruit ! You have perhaps visited at your 
 grandparents' farm where there is an orchard still 
 bearing fruit that was set out when your grandfather 
 was a young man. Apple trees, if well taken care of, 
 will bear from twenty to fifty years. 
 
 Propagating a peach tree. You can easily propa- 
 gate a peach tree of any desired variety. Plant the 
 seeds in the fall covering them lightly so that freezing 
 will break the hard shell. In the spring thin to 
 about six inches. In the late summer or early fall 
 bud the seedlings just where they stand in the nursery 
 row. First take a one-year twig from the variety 
 of peach that you wish to produce. Trim off the 
 leaves leaving the petioles sticking out like little 
 stubs. Nurservmen call this a "budding stick." In 
 
FRUIT AND FRUIT TREES 
 
 279 
 
 the bark of the seedling make a, T slit about two 
 inches from the ground. In warm climates this is 
 always made on the north side. Cut a bud from the 
 stick with a slice of the bark and a little wood, and 
 using the leaf petiole as a handle slip the bud into 
 the T slit pushing it well down and covering it with 
 the little flaps of bark at the top. "Wrap with raffia 
 or grafting thread. "See Fig. 57. It is often well 
 to place two or three buds in the same stock. If the 
 bud does well it will grow fast to the stock at the 
 cambium layer. In the spring cut off the top of 
 
 Fig. 57. Budding. A, Budding stick with one bud cut out, a; 
 B, Seedling 1 tree with "T" slit, b ; C, Same as B showing flaps of bark 
 folded back; D, Bud in place; E, Bud wrapped with cord or raffia. 
 
 the seedling and leave the strongest bud to grow 
 and develop into your peach tree. 
 
 In the fall or the following spring the tree will 
 
280 STUDIES IN SCIENCE 
 
 be ready to transplant. In three or four years it will 
 bear fruit. 
 
 Orange trees also are propagated by budding. 
 Seeds from the sour oranges or lemons are used for 
 the stocks because they are hardier than those of 
 the sweet oranges. Great care must be taken to plant 
 the seeds as soon as they are removed from the fruit. 
 If they are allowed to dry they will not germinate. 
 They are planted in rows about two feet apart. After 
 six months or a year they are transplanted to rows 
 from three to four feet apart, the plants standing 
 about ten inches apart. At the end of three or four 
 years they are budded, usually in the fall. After a 
 full season's growth they are set out in the orchard 
 and in three years are beginning to bear fruit. 
 
 Cherries, plums and prunes are propagated by bud- 
 ding; pears and quinces by grafting or budding. 
 
 CARE or FKUIT TREES 
 
 Cultivation. How far apart are the cherry trees 
 in your orchard or fruit garden? The pears? 
 Peaches? Apples? Oranges? Lemons? What is the 
 condition of the soil between the rows? Are other 
 plants grown here ? What do you find in old orchards ? 
 Young ones? Young orchards should be cultivated 
 frequently for two reasons : 1. To keep down weeds. 
 2. To conserve the moisture. 
 
FRUIT AND FRUIT TREES 281 
 
 Pruning. When are the fruit trees in your neigh- 
 borhood pruned? Who does the work? What tools 
 are used? Why is pruning necessary? Examine a 
 pruned tree. Is each branch cut close to the stem 
 or is a portion left as a stub? Watch the scar for a 
 number of weeks to find out how it heals. What has 
 the cambium to do with this? Examine an old scar. 
 
 There are at least three good reasons for pruning 
 fruit trees : 1. To secure a well formed tree. This 
 means proper pruning when the tree is young. 2. To 
 remove superfluous branches or suckers so that the 
 fruit bearing branches may get more nourishment. 
 3. To keep the tree free from old, non-bearing stems 
 and branches. A well pruned tree has just enough 
 branches to permit the free circulation of air and the 
 right amount of sunlight. 
 
 The usual time to prune is in late winter or early 
 spring. Some fruit growers, however, prune in the 
 summer. To prune moderately each year is better 
 than to prune heavily every three or four years. 
 
 A good pruner removes the branch close to the 
 stem from which it grows. A stub should never be 
 left sticking out from the stem. It does not heal 
 quickly and is likely to foster the growth of fungous 
 diseases. From your study of an apple tree you know 
 that spurs grow out from the sides of the branches 
 and produce the next year's fruit. Care must be 
 
282 STUDIES IN SCIENCE 
 
 taken not to remove too many spurs and thus reduce 
 the crop. 
 
 Spraying. Make a list of insect enemies of fruit 
 trees. A list of fungous diseases. How may these 
 be combated? What different kinds of sprays have 
 you seen? What time of year are the trees sprayed? 
 What materials are used? 
 
 A mixture designed to kill insects is called an 
 insecticide; one to kill fungi is a fungicide. 
 
 In treating fruit trees a fungicide and insecticide 
 are frequently combined and sprayed together. Some 
 common mixtures are arsenate of lead and lime-sul- 
 phur; arsenate of lead and Bordeaux mixture; Paris 
 green and Bordeaux mixture. 
 
 Fruit projects. Plan to care for your fruit trees 
 if you have an orchard. Look after the spraying and 
 pruning. If you lack time to care for the entire 
 orchard choose three or four trees and see whether 
 you can improve the quantity and quality of the fru?t 
 by your care. Keep a record of your expenditures, 
 receipts and profits. Determine from your experience 
 whether it pays to give some time to the care of fruit 
 trees. 
 
CHAPTER XVIII 
 
 DOMESTIC ANIMALS 
 
 1. CATTLE 
 
 Material, Cows of the community, milk, Babcock 
 tester, pictures of different breeds of cattle. 
 
 Study. Cattle may be grouped into two great 
 classes; those kept for dairy purposes, known as 
 dairy cattle, and those raised for meat, known as beef 
 cattle. Decide what kinds are found in your commu- 
 nity. 
 
 Make a careful study of a cow. Write the names 
 of the different parts of the body. Note the shape 
 of the body and the height. What sense organs have 
 cows! Describe the eyes, ears, nose. Watch the cow 
 crop grass. How does she do itf Watch her chew- 
 ing her cud. Explain the movements that you see 
 in the neck at this time. 
 
 Describe her feet and legs. Locate the joints in 
 the fore leg that correspond to those in your arm. 
 Locate those in the hind leg that correspond to those 
 
 283 
 
284 STUDIES IN SCIENCE 
 
 in your leg. How many toes can you find! How 
 many are used to walk upon? 
 
 Discussion. In order to talk intelligently about a 
 cow and to make a score-card for judging cattle the 
 various parts have been given names. See Fig. 58. 
 
 You find that the eyes of a cow are situated so 
 
 Fig. 58. Diagram showing external parts of a cow. 
 
 1. Muzzle. 2. Jaw. 3. Face. 4. Fore-head. 5. Throat. 6. Neck. 
 7. Withers. 8. Shoulder. 9. Chest. 10. Back. 11. Ribs. 12. Loin. 
 13. Rump. 14. Rump. 15. Hips. 16. Tail. 17. Thigh. 18. Udder. 
 19. Belly. 20. Milk Veins. 
 
 that she has a fair range of vision in all directions. 
 She can turn her ears in any direction to catch sounds. 
 Her hearing is very keen. The sense of smell seems 
 well developed also. It is perhaps aided by the mois- 
 ture which always stands on her nose. What animal 
 
DOMESTIC ANIMALS 285 
 
 that uses its sense of smell a great deal has a cool, 
 moist nose? 
 
 Cows eat rapidly and swallow their food after 
 chewing it very slightly. This food passes into the 
 first stomach. From here it goes into a small apart- 
 ment where it is made into balls. The cow then lies 
 down or stands quietly while she brings back to the 
 mouth one ball of food after another, chews it 5 and 
 swallows it again. This is called chewing the cud. 
 This time it goes into the true, stomach where it is 
 digested. You can see the balls of food move upward 
 along the neck. If you look into a cow's mouth you 
 find eight front teeth on the lower jaw. There are 
 no front teeth on the upper jaw. Instead, there is a 
 hard plate. There is a space without teeth on the 
 lower jaw. Each jaw has twelve grinding teeth, six on 
 each side. 
 
 The cow walks on two toes. Above these you can 
 see two other toes. The first joint in the front leg 
 that looks as if it might be the knee corresponds to 
 your wrist. The elbow joint is up near the body, 
 while the shoulder joint is about half way up the side 
 of the body. The ankle, knee and hip joints occupy 
 similar positions in the hind leg. 
 
 A dairy cow differs in shape from a beef cow. She 
 is said to be wedge-shaped. The wide part of the 
 wedge is at the back, the narrow part or point in 
 
286 
 
 STUDIES IN SCIENCE 
 
 front. A good dairyman looks for other characteris- 
 tics. The cow must have what he calls open confor- 
 mation; that is, a wide space between the hip bones, 
 the ribs wide and far apart, the vertebrae long, and 
 the paunch large and deep. She must also have dis- 
 tinct dairy qualities; the skin loose, dry, and flexible, 
 the hair soft and silky, the eyes bright and project- 
 
 rig. 59. A dairy cow. 
 
 ing a little, the face smooth and the head well pro- 
 portioned. The udder must be flat across the bot- 
 tom, attached high in the rear, and extending well 
 forward. 
 
 The form of the beef cow makes possible the taking 
 on of a large amount of flesh. A beef cow is almost 
 
DOMESTIC ANIMALS 287 
 
 rectangular in form, with a short heavy neck and short 
 legs. The body has a smooth, compact appearance. 
 
 Dairy breeds. Make a list of the dairy breeds you 
 know. Look through farm journals and other papers 
 for pictures of different breeds of cattle. Cut these 
 out and group them to form a booklet. 
 
 The common dairy breeds are Jersey, Guernsey, 
 Holstein-Friesian and Ayrshire. 
 
 Jersey cattle came originally from Jersey Island 
 in the English Channel. They are small cows of a 
 fawn or grayish brown color, shading toward black 
 at the head and feet and along the back. They have 
 black noses. 
 
 Guernsey cattle originated on Guernsey Island not 
 far from Jersey. They are a little larger than the 
 Jersey, are about the same color but frequently have 
 white markings, with flesh colored noses. These two 
 breeds are similar in the quality of milk, both giving 
 a rather small quantity but very rich in butter fat. 
 The Jerseys are numerous in central and southern 
 United States, the Guernseys in the northern states 
 and Canada. 
 
 Ayrshire cattle came originally from the county 
 of Ayr in Scotland. They are larger than the Jer- 
 seys, are smooth, well formed cattle. The color is 
 white with spots and streaks of red. 
 
 Holstein-Friesian came from Holland. They are 
 
288 STUDIES IN SCIENCE 
 
 much larger than the other dairy breeds, and are 
 black and white in color. They are the greatest milk 
 producers, but their milk is usually rather low in 
 butter fat. 
 
 Care and food of dairy cattle. What food do dairy 
 cows eat during the summer? During the winter? 
 Make a list of the different kinds of food used. 
 
 In some localities cows subsist during the summer 
 almost wholly upon pastures. In other places dairy- 
 men do not use pastures at all but feed soiling crops 
 and grains during the summer. In the winter hay of 
 different kinds, grains, silage, and ground feeds are 
 used. 
 
 It is very important that cows be fed properly if 
 they are to keep in good condition and give a profit- 
 able amount of milk. They must have enough food 
 and the proper kinds. This means that they must 
 have the right proportion of protein, carbohydrates 
 and fat. 
 
 Protein is necessary for the making of muscle, 
 blood, connective tissue and the protein part of milk. 
 It should constitute r.t least one-sixth of a cow's 
 ration during the milking season. It may be sup- 
 plied by any of the following foods: alfalfa, clover, 
 cow-peas, soybeans, bran, cotton-seed meal, linseed 
 meal, and oats. 
 
 Carbohydrates and fats are. required for energy, 
 
DOMESTIC ANIMALS 289 
 
 heat, fat for the body, sugar and fat for milk. Fats 
 are found to some extent in all feeds. The common 
 carbohydrate feeds are corn, silage, oat straw, sugar 
 beets, and beet pulp. 
 
 When these foods are fed in the proper proportion 
 they are said to form a balanced ration. Many 
 agricultural stations have worked out tables of bal- 
 anced rations for the use of dairymen and other 
 farmers. 
 
 The following two tables were arranged by the 
 Purdue Agricultural College: 
 
 Ration I Ration II 
 
 Corn silage 30 pounds Sugar beets 25 pounds 
 
 Cow-pea hay 10 pounds Alfalfa hay . 10 pounds 
 
 Corn stover 2 pounds Corn stover 5 pounds 
 
 Corn 6 pounds Corn 5 pounds 
 
 Cotton-seed meal ....1.5 pounds Dried brewer's grains.. 5 pounds 
 
 A good dairyman, however, compounds his own 
 rations to fit the weight and milk production of his 
 individual cows. Usually a cow should be given 1 
 pound of leguminous hay and 3 pounds of silage for 
 each 100 pounds of live weight, and 1 pound of grain 
 for each 3 pounds of milk produced. 
 
 Beef cattle. There are several different breeds in 
 America. Shorthorns are probably the most widely 
 raised due to the fact that many of them produce 
 a fair amount of milk as well as beef. They are of dif- 
 ferent colors, some red, some red and white, some 
 
290 STUDIES IN SCIENCE 
 
 roan, and some almost pure white. The red ones are 
 probably the most numerous. They are sometimes 
 called Durhams. 
 
 Herefords are becoming more and more common 
 in many parts of the country. They are the cattle 
 
 Fig. 60. A beef cow. 
 
 you often see in pastures with red bodies and white 
 faces and legs. 
 
 We have two kinds of black cattle, Aberdeen- Angus 
 and Galloways. The Angus are heavier than the 
 Galloways. During the winter the coats of the latter 
 become very long and shaggy. 
 
 The food of beef cattle. The food of beef cattle 
 also should receive special attention. Since the 
 object is to produce the greatest amount of meat pos- 
 sible, a ration is planned with this in view. More 
 
DOMESTIC ANIMALS 291 
 
 carbohydrates and fats are fed in proportion to the 
 protein to beef cattle than to dairy cows. Instead 
 of feeding all grain, silage mixed with concentrated 
 foods as linseed meal, cotton-seed meal and gluten is 
 coming more and more into use. 
 
 Housing cattle. Housing cattle properly is quite 
 as important as good food. A cow barn should be 
 built so that the cows will have plenty of air and 
 light and be comfortably warm. It should also be 
 constructed with the idea of cleanliness. The best 
 barns have hard floors, usually cement. The stalls 
 have a shallow gutter at the back which slopes 
 slightly to one end so that it may be washed out eas- 
 ily with a hose. In front is a water-tight trough used 
 for food. This too has a slight slope and may be 
 easily washed out. 
 
 Composition of milk. Of what is milk composed? 
 You know by tasting that it is sweet. This means 
 that it has sugar in it. We call this milk-sugar. 
 Another of the important ingredients is fat. This 
 is known as butter fat. There is also some protein 
 in it and a very small amount of minerals. All the 
 rest of the milk, by far the largest part, is water. 
 
 The following table shows approximately the pro- 
 portions of each ingredient in milk of average quality : 
 
 Butter fat 4.0 per cent 
 
 Proteid . , 3.3 " " 
 
292 STUDIES IN SCIENCE 
 
 Sugar 5.0 " '" 
 
 Minerals .7 " " 
 
 Water 87.0 " " 
 
 .. ~ 
 
 Experiment. Place some fresh milk in a bottle, 
 straight tumbler, or test tube. Allow it to stand a 
 few hours. What happens! Why does the cream 
 come to the top 1 What does a piece of wood do when 
 put into water! Why does it float upon the water! 
 Cream comes to the top of milk for the same rea- 
 son; that is, because it is lighter than milk. Measure 
 the height of the milk, of the cream. Calculate what 
 per cent is cream. Cream is largely butter fat. 
 
 Separation. What methods are used in separating 
 cream from milk ! Some people use crocks or shallow 
 pans. Fresh milk is put into these and allowed to 
 stand. The cream rises to the top and is then skimmed 
 off with a flat skimmer. This is the old-fashioned 
 method but is still used by many people. It is by far 
 the poorest method known. It has been estimated that 
 at least one-fourth of the butter fat is left in the 
 skimmed milk when this method is used. 
 
 Some people use a deep can, at least twenty inches 
 in depth. The milk is placed in it and is usually kept 
 cool by placing the can in water. Sometimes the 
 cream is skimmed off as it is from the shallow pans, 
 but a better wav is to have a faucet in the bottom 
 
DOMESTIC ANIMALS 293 
 
 of the can. When the cream has risen the faucet is 
 turned and the milk is drained off. Then the cream 
 is drawn off through the faucet. Much more butter 
 fat is obtained in this way than by the shallow pan 
 method. 
 
 Many people use a separator by which the milk 
 and cream may be separated at once without allowing 
 the milk to stand. A separator is a machine which 
 is worked by means of a crank. The main part is a 
 cylindrical bowl that revolves rapidly. The milk is 
 placed in this bowl. What happens to the milk in 
 this cylinder! Tie a piece of chalk or some other 
 object to a string about eighteen inches in length. 
 Take hold of the end of the string and whirl it rap- 
 idly. Can you feel the string pulling? Let go while 
 you are whirling. What do the string and weight 
 do? The force that made the string pull on your 
 hand and caused it to fly off in a straight line when 
 you let it go is called centrifugal force. It is the 
 force that causes revolving bodies everywhere to 
 move away from the center. Did you ever notice 
 how mud .and water fly from a rapidly revolving 
 wheel f Since milk is heavier than cream, which will 
 move more rapidly away from the revolving center? 
 You can readily see that since the milk is heavier 
 it will move toward the outside of the cylinder while 
 the cream is forced toward the inside. There is an 
 
294 STUDIES IN SCIENCE 
 
 opening toward the outside through which the milk 
 pours out in a stream and an opening toward the 
 inside through which the cream pours forth. 
 
 In many country districts milk is sent directly to 
 a creamery instead of being separated at home. In 
 many places large cans are furnished by creamery 
 companies. A man comes around once each day, 
 collects the cans of milk, and takes them to the 
 creamery. The cream and the milk are separated at 
 once, and usually the milk is put back into the cans 
 and returned to the farms, where it is used to feed 
 calves and pigs. What is done with the cream at the 
 creamery? What is usually done with the cream that 
 is kept at home? 
 
 Butter. Is butter made from sweet or sour cream? 
 You know from your study of bacteria that there are 
 organisms which under right conditions cause milk 
 and cream to sour. Sour cream makes better flavored 
 butter than sweet cream. In homes the cream is 
 allowed to stand until it sours or ''ripens." In cream- 
 eries a small amount of sour cream, or other substance 
 containing a number of cream-souring bacteria called 
 a starter, is placed in the fresh cream so that it 
 ripens in a short time. 
 
 Describe different kinds of churns that you have 
 seen. What is the principle of churning? The cream 
 is agitated violently enough to force the fat particles 
 
DOMESTIC ANIMALS 295 
 
 together. They strike against each other and adhere, 
 the particles growing larger and larger. It is not 
 best to continue churning until the particles are all 
 joined together in one great mass. Churning should 
 be stopped when the particles are not much larger 
 than a pea. If the masses are too large it is much 
 harder to remove all the milk and water from the 
 butter. 
 
 Care of milk. Besides the bacteria which cause 
 milk to sour, there are likely to be many other kinds 
 in milk, some of which produce diseases. Since bac- 
 teria find milk a favorite field, what care should be 
 taken to prevent too many of them from getting into 
 it? First of all, great care should be exercised in 
 milkitfg. The milker should have clean clothing and 
 clean hands. The cow should be brushed to get rid 
 of dust, and the udder should be washed or wiped 
 clean. A covered milk pail is preferable to an open 
 one. It is made with an opening just large enough 
 to allow the stream of milk to flow in. 
 
 The second step in caring for milk is straining. 
 A wire strainer should not be used. Cheesecloth and 
 absorbent cotton make the best strainers. A layer 
 of cotton is placed between two or four folds of 
 cheese cloth. The cotton should be destroyed after 
 using once. The cheesecloth should be scalded and 
 placed in the sun. When possible all other utensils 
 
296 STUDIES IN SCIENCE 
 
 used with the milk should be cleansed in a similar 
 manner. 
 
 The third step is cooling. Milk should be cooled 
 as. quickly as possible. The best dairy farms have a 
 special apparatus for cooling milk rapidly. 
 
 Experiment. To determine the effect of cooling 
 upon the growth of bacteria in milk. 
 
 Divide a cupful of new milk into two equal parts 
 putting half into a bottle numbered one, the other 
 half into a bottle numbered two. Place the first 
 bottle at once into a pan of very cold water. Leave 
 the other in the room. When bottle number one is 
 thoroughly cooled stand it beside number two and 
 compare as to appearance. Which sours first? Give 
 reasons. 
 
 The prompt cooling retarded the growth of bac- 
 teria that were in the milk. In number two the bac- 
 teria began at once to feed and multiply causing 
 the milk to sour. 
 
 Testing the milk. In order to determine whether 
 or not a cow is producing enough milk and butter fat 
 to make her a profitable investment, the amount of 
 milk should be weighed. This means that the milk of 
 each cow should be weighed separately and a record 
 kept. Every good dairy, or farm where a number of 
 cows are kept, has a pair of scales hanging in a con- 
 venient place with a sheet of paper for recording 
 
DOMESTIC ANIMALS 297 
 
 weights of milk. At the end of a season the dairy- 
 man can easily determine which cows are worth 
 keeping and which are not. 
 
 To determine the amount of butter fat that a cow 
 produces frequent tests with the Babcock tester are 
 necessary. This tester may be bought for from four 
 to ten dollars depending upon the number of bottles. 
 Directions for using come with each machine. Any 
 seventh or eighth grade boy or girl can soon learn 
 to use the tester. The milk of each cow should be 
 tested at least once a month. It will be interesting to 
 test skimmed milk from a shallow pan, a deep can, 
 and a separator to determine which method leaves the 
 least fat in the milk. 
 
 Milk and health. Milk provides one of the most 
 important foods for. mankind. It is especially valua- 
 ble for children since it contains all of the food 
 nutrients needed by the growing child. Thousands 
 of children are more or less dependent upon it for 
 food. 
 
 Cattle are subject to the dread disease, tuberculosis, 
 and a cow that has this disease may infect human 
 beings through her milk. In many places herds are 
 carefully inspected and once a year given the tuber- 
 culin test which makes it possible to detect any indi- 
 viduals that have the disease. These are isolated 
 from the herd and in some cases killed. 
 
298 STUDIES IN SCIENCE 
 
 Milk that is suspected of containing tubercular 
 bacteria should be sterilized or pasteurized. 
 
 Sterilization kills all the bacteria, but boiling 
 changes the flavor and digestibility of milk and is 
 not very desirable. Pasteurization kills all active 
 bacteria, The bacterial spores, which are inactive, 
 are not killed and in time become active and cause 
 the milk to sour. However, bacteria spreading such 
 diseases as tuberculosis, typhoid, etc., do not have 
 the spore forms and are all killed by this process. 
 
 Value of cattle. Make a list of the uses of cattle, 
 and of the industries that are dependent upon them. 
 These two lists will help you to realize how valuable 
 cattle are. The most important products are milk, 
 meat, and leather. Some of the different milk prod- 
 ucts are butter, cheese, condensed milk, milk powders, 
 and ice cream. There are a large number of by- 
 products. Fertilizers are made from blood and bones, 
 the hair is used in upholstering, brush handles and 
 buttons are made from horn and bone, glue and gela- 
 tin are made from the hoofs and connective tissue. 
 
 Projects. If you live in the country you may easily 
 undertake one or two projects in connection with your 
 cattle study. 
 
 The calf project is one suggested by the Depart- 
 ment of Agriculture that may interest boys and girls. 
 Take a young calf, care for it for a year or six 
 
DOMESTIC ANIMALS 299 
 
 months. Keep a careful record of the feed, amount 
 and cost. 
 
 Find the gain in pounds at the end of the period 
 and the cost per pound of gain. 
 
 Keep a record also of the difficulties you meet and 
 how you overcome them. Note any other facts of 
 interest that you learn in raising your calf 
 
 A second project that is worth while is testing 
 milk for butter fat with the Babcock tester. Several 
 cows should be chosen and tests made of the milk. 
 To make a fair test, samples of milk from each cow 
 for four consecutive milkings should be tested once 
 a month. Careful records should be kept and con- 
 clusions drawn as to the quantity of butter fat pro- 
 duced by each cow in a given time. 
 
 Still another valuable project is testing cows for 
 amount of milk produced. This means taking daily 
 weights of the milk from each cow for six months 
 or any definite period agreed upon. 
 
 2. HORSES 
 
 Types of horses. Observe the horses in your com- 
 munity. Are they all of the same kind or breed? 
 State some of the differences as to size, build and 
 color that you have noticed. These differences indi- 
 cate to some extent the differences in breed. There 
 are three important types of horses known : the draft 
 
300 
 
 STUDIES IN SCIENCE 
 
 horse, the coach or carriage horse, and the roadster 
 or trotter. 
 
 The draft horse is heavy, has rather short, heavy 
 legs, a short, thick neck and broad, deep chest 
 and shoulders. There are two other classes of heavy 
 horses that are closely related to the draft breeds. 
 
 Fig. 61. A good farm team. 
 
 These are known as chunks and wagon horses. 
 Chunks are light weight draft horses. Wagon horses 
 are rather heavy but more active than the draft or 
 chunks. Artillery horses and those used in fire 
 departments are of this type. 
 
DOMESTIC ANIMALS 301 
 
 Carriage horses are not common in America. More 
 attention is given to raising them in the East and 
 South than in the West. These horses are somewhat 
 lighter than wagon horses, have long arched necks, 
 and are usually of graceful appearance. 
 
 The third type, the roadster, is a tall slender horse 
 with a small head, a long neck, and a rather thin 
 light body. 
 
 What is the use of the roadster? The name, of 
 course, suggests the use. This horse must be able 
 to travel rapidly and endure the strain of travel 
 for a long time. Why should a roadster be much 
 lighter in weight than a draft or work horse? Do 
 you know of any true carriage horses in your neigh- 
 borhood? How do they compare with the heavy 
 work horses and the roadsters? 
 
 Uses of horses. Observe horses in the neighbor- 
 hood and note which seem to fit the description of any 
 of these various types. Look in farm papers and 
 magazines for pictures of; horses of different kinds 
 and start a chart of these as you did of the different 
 breeds of cattle. What are the uses of the different 
 kinds? The largest draft horses are used in large 
 cities to draw immense loads of various kinds. Do 
 you know how much a heavy draft horse weighs? 
 The heaviest draft horses weigh over 2,000 pounds, 
 medium drafts from 1,600 to 1,700 pounds, and light 
 
302 STUDIES IN SCIENCE 
 
 draft from 1,500 to 1,600 pounds. Do these horses 
 move rapidly or slowly? 
 
 Make a list of the different kinds of work that 
 farm horses do. Is any work now done by horses that 
 was once done by man? Inquire of your parents in 
 regard to this matter. Perhaps some of them will 
 remember when corn was planted by hand and all 
 small grains sowed broadcast by hand. To what 
 extent have gasoline or steam engines taken the 
 place of horse power in your neighborhood? Think 
 of tractors, threshers, corn-shellers, automobiles, etc. 
 While you do not remember, your parents will, that 
 not many years ago all threshing machines and corn- 
 shellers were run by horse power. 
 
 Description. Study a horse. Use good pictures if 
 you do not have an opportunity to study a live horse. 
 Make a list of the parts with a description of each. 
 How high is the horse? Compare the length of the 
 legs with the height. Note movements of the ears. 
 What is the advantage in the position of the ears? 
 Describe the eyes, the nostrils. Note the thick lips 
 and the teeth. How many front teeth do you see? 
 Note the body covering. What are the uses of the 
 mane and tail? 
 
 Examine the feet and legs. Note differences 
 between the front and hind legs. Determine the joints 
 corresponding to those in your own body. Show how 
 
DOMESTIC ANIMALS 303 
 
 the leg and foot of a horse are adapted for speed and 
 for travel upon dry ground. How does the tail differ 
 from that of the cow! Compare the foot of the 
 horse with that of the cow. Which foot will endure 
 more travel on hard ground! Which will likely bear 
 the animal up better on soft ground! Why! 
 
 Discussion. The horse is among the best loved 
 of all domestic animals. In some ways it seems more 
 intelligent than other animals. It is high-spirited 
 and sensitive. You noticed how the ears move as if 
 they were on a pivot, ready to catch every sound. 
 The eyes are placed so as to give a w r ide range of 
 vision. The nostrils flare. The sense of smell is very 
 keen. The long legs and comparatively light body 
 show that the horse is well adapted for travel. The 
 height of a horse is measured in hands. One hand 
 is four inches. 
 
 The teeth of the horse are interesting. When a 
 horse is full grow^n he has forty teeth. On each jaw 
 there are six incisors, two canines, and twelve molars. 
 The incisors are prominent and sharp enabling the 
 horse to crop grass very close to the ground. A man 
 who knows horses can tell the age of a horse by exam- 
 ining the incisors. A colt's teeth are temporary and 
 are gradually replaced by the permanent set. 
 
 The middle pairs of permanent incisors, above and 
 below, appear when the horse is three years old; the 
 
304 STUDIES IN SCIENCE 
 
 next pair at four, and the third pair at five years. 
 The new teeth have deep cups or indentations in the 
 middle of the biting surface. As the teeth are used 
 the sides wear down and the cups gradually disap- 
 pear. When the horse is six years old the cups in 
 the middle pair of teeth on the lower jaw have disap- 
 peared. At seven the cups are gone from the second 
 pair. At eight the cups have disappeared from all 
 the lower incisors but are still present in the upper 
 jaw. At nine they are gone from the upper middle 
 pair, at ten from the second pair, and at eleven from 
 the third pair. After this the shape and direction 
 of the teeth indicate something of the age. 
 
 The horse walks on its middle toe, which is large and 
 has developed a horny covering called the hoof. The 
 rudiments of two other toes can be seen at the back 
 of the foot. 
 
 The joints about half way up each leg correspond 
 to our wrist and ankle joints. The elbow and knee 
 joints are close up to the body. The round hoof of 
 the horse is adapted to travel on dry plains, while 
 the split hoof of the cow is adapted to wet marshy 
 places. The long leg is adapted for rapid travel. 
 
 The body is covered with short hairs that lie close 
 to the skin. When properly cared for they make a 
 beautiful, glossy coat. The hair is shed every year. 
 It is much thicker in the winter than in summer. 
 
DOMESTIC ANIMALS 305 
 
 Care of horses. One of the first things to consider 
 in caring for a horse is its food. Make a list of the 
 various foods horses eat. List the kinds of hay used 
 in the neighborhood. How many feed timothy alone? 
 Clover alone? Timothy and cloyer mixed? Alfalfa? 
 Straw? Who feed oats? Who corn? Compare these 
 foods as to the amount of different nutrients. Which 
 contain the greater amount of roughage? Grains 
 contain a high per cent of carbohydrates and not 
 much protein. Leguminous hays contain proteid and 
 all hays roughage. Since carbohydrates produce fat 
 and heat, you can see why foods containing carbo- 
 hydrates should be fed to horses in greater quantities 
 in winter than in summer. Why do working horses 
 need different kinds of food and larger amounts than 
 idle horses? When a horse is working he is using up 
 muscle just as boys do when they exercise. There- 
 fore a working horse should be fed more proteid foods 
 because these foods help to build up muscle. He also 
 needs carbohydrate and fats to supply energy. Like 
 most animals, the horse needs some salt, and a small 
 amount should be given him at least every two weeks. 
 
 Balanced rations have been arranged for horses as 
 well as for cattle. A 1,200 pound horse at heavy work 
 requires 2.16 pounds of proteid, 14.4 pounds of carbo- 
 hydrates, and .6 pounds of fat. On this basis the 
 following rations have been worked out: 
 
306 STUDIES IN SCIENCE 
 
 No. 1 Pro. C. H. Fat. 
 
 Oats, 18 pounds 1.65 8.46 .75 
 
 Timothy hay, 14 pounds 39 6.08 .19 
 
 No. 2 
 
 Corn, 15 pounds 1.18 10.00 .64 
 
 Clover hay, 14 pounds 95 5.02 .24 
 
 By adding the columns you find that each ration 
 approximates the amount required. The farmer 
 should use the ration that is most economical for him. 
 
 It is of great importance to observe regularity in 
 the feeding of horses. Horses more than any other 
 domestic animals seem to like order and regularity. 
 They seem to watch and know when feeding time has 
 arrived and become nervous if they are not fed. The 
 horse should receive its heavy meal at night after 
 the day's work is done. There is a good reason for 
 this. The stomach of the horse is small compared 
 with that of other large animals; hence when horses 
 are fed in the evening they have plenty of time to 
 chew and digest their food. A good rule to follow 
 for a working horse is to feed one-fourth the daily 
 ration in the morning one hour before going to work, 
 one-fourth at noon, and one-half in the evening. 
 
 The same care should be exercised in watering 
 horses as in feeding them. Most experts agree that 
 horses should be watered before meals rather than 
 afterwards, the only exception being, perhaps, with 
 the morning meal. Great care should be taken to 
 
DOMESTIC ANIMALS 307 
 
 avoid watering horses when they are very warm. 
 A good horse may be ruined, sometimes killed, by 
 drinking a large quantity of water when in a heated 
 condition. 
 
 Horses should be housed in comfortable, well-aired 
 barns. They should be kept clean by currying and 
 rubbing twice a day, and the legs should receive 
 special attention. A rubbing down is quite necessary 
 in the evening after the day's work. The horse will 
 rest much better and be in better condition for work 
 the next day. During cold weather horses should be 
 blanketed when standing still, especially when they 
 have traveled some distance and are warm and per- 
 spiring. 
 
 The harness. Harness has two uses; one is to 
 enable the horse to do its work, the other is to enable 
 the driver to control the horse. Name all the parts 
 of the harness you know. What parts help the horse 
 in pulling a load? What parts aid the driver in con- 
 trolling the horse? What parts of the horse are 
 likely to be injured by poorly fitting harness? 
 
 Discussion. Since the horse uses its shoulders in 
 moving a load, the collar, hames, and traces are the 
 parts that aid it most. The bridle, bit, and lines 
 enable the driver to control and guide the horse. 
 Many horses suffer greatly because the harness does 
 not fit properly. A poorly fitting collar results in a 
 
308 STUDIES IN SCIENCE 
 
 sore neck or shoulder. If the bridle and bits are not 
 right a sore mouth will result. An improperly fitting 
 crupper may result in a sore tail. A riding horse 
 should have a saddle that fits properly. 
 
 Harness should be thoroughly cleaned and oiled 
 to prevent its becoming hard and stiff. 
 
 Training horses. Bad habits in horses are usually 
 due to improper training. It should always be re- 
 membered that horses rarely forget a trick or any- 
 thing that they have once experienced. If they become 
 frightened at a piece of paper in the road and run 
 away they are very likely to be frightened the next 
 time they see a piece of paper. Thus it is very impor- 
 tant that horses should be trained carefully so that 
 they may have nothing to remember that will later 
 be injurious either to themselves or to their owners. 
 
 In breaking a horse one should be firm yet kind and 
 gentle. Horses should be trained to stand still while 
 being harnessed, to stop promptly at the word 
 "whoa," and to move backward at the word "back." 
 A horse properly trained will not start forward until 
 he is given the word or signal to start. Have you 
 not seen horses that began to move the moment the 
 driver took the lines in his hand, instead of waiting 
 to be told to go? Every farm boy should learn how 
 to manage a horse and do it in the right way. 
 
 History. Horses have been known since the begin- 
 
DOMESTIC ANIMALS 309 
 
 ning of history. Our ancestors in prehistoric times 
 tamed wild horses and used them in hunting other 
 animals that ran rapidly. The horse is one of the 
 fleetest runners known among animals. 
 
 The horse was brought to America from Europe. 
 In Europe there are two distinct types of horses: 
 a heavy horse that was found in England in the 
 western part of the continent, and the Arabian horse 
 that was brought into Europe at the time of the 
 Crusades. The wild horses that we read about in 
 America were horses that escaped from the early 
 Spanish explorers and roamed over the prairies until 
 they became wild. 
 
 Colt project. Any boy or girl who is interested 
 may with profit undertake a colt raising project 
 similar to the calf project. Eecords should be kept 
 of the cost, the management, and the condition of the 
 colt at the beginning and the end of the peirod. 
 
 3. SWINE 
 
 Material. Hogs of the neighborhood, pictures of 
 mature and young pigs. 
 
 Study a hog. Note the shape of the body, the 
 length and size of the legs, the body covering. How 
 does the hair compare in thickness with that of a 
 cow? Examine the feet. Find the number of toes. 
 
310 STUDIES IN SCIENCE 
 
 Decide on what part of the foot the pig walks. Has 
 the divided hoof any advantage for the hog? Are 
 the rear toes of any use? What is the shape of the 
 face? Describe the ears, eyes and nose. Look espe- 
 cially at the end of the nose. Note the position of 
 the mouth. 
 
 Make a list of the different kinds of food that pigs 
 eat. Describe their habits of feeding. How does the 
 nose aid in obtaining food? Determine whether or 
 not all the different classes of teeth are present. 
 Describe the habits of pigs with reference to mud 
 and water. 
 
 How many different breeds of hogs are represented 
 in your district? How do they differ in shape, size, 
 color, etc. ? What is the greatest number of hogs 
 kept by any one farmer? For what purpose are they 
 kept ? At what , age are hogs usually marketed ? 
 What is fed to hogs that are being fattened for 
 market ? 
 
 Discussion. Hogs or swine have been domesticated 
 since a very early time. Their origin is not definitely 
 known. It is believed, however, that they were first 
 domesticated in Asia and are descendents of the wild 
 boar. (Note that the term boar originally had the same 
 meaning as our word hog.) It is also probable that 
 later the wild swine of Europe was domesticated in 
 that country. Wild hogs are still found in some parts 
 
DOMESTIC ANIMALS 311 
 
 of Europe and Asia, and in some of our southern and 
 southwestern states. These latter are not native to 
 America, but are the descendants of the domestic 
 hogs that were brought over here by the early Span- 
 ish explorers. These hogs, like the wild hogs of 
 Europe, are thin and sharp-nosed. They are com- 
 monly known as razor backs. They subsist upon 
 herbs, nuts of trees, roots, and insects found in the 
 soil. 
 
 The body of the hog, as compared to the height, is 
 long and deep. The legs are short and each foot 
 has four toes. The two front toes are large and it is 
 upon these that the hog walks. The hind toes are 
 small and placed higher up than the front ones. They 
 are of no use when the hog walks on dry land, but 
 when it walks on low, marshy ground these hind toes 
 help to keep it from sinking into the soft earth. 
 
 The body is covered rather scantily with very 
 stiff hairs called bristles. They are ' strongest and 
 stiffest along the back. Under the bristles is a thick 
 leathery skin. On most hogs the hairs are so scat- 
 tered that the skin shows through plainly over the 
 entire body. 
 
 The bristles of the hog are used in the making of 
 brushes. Shoemakers use them in making wax-ends 
 with which they sew shoes. 
 
 The general shape of the head of the hog is tri- 
 
312 STUDIES IN SCIENCE 
 
 angular, the forehead curving inward and the cheeks 
 outward, more or less according to the breed. The ears 
 are of interest because of their large size. In some 
 breeds they stand up, while in others they droop. 
 This characteristic aids in distinguishing breeds. 
 The eyes, though small, have a keen vision. The nose 
 is one of the pig's most interesting features. It ends 
 in a fleshy disk, often called the snout. This is 
 exceedingly sensitive so that it can detect the solid 
 grains of oats or wheat in a pile of chaff. It is also 
 so strong the hog can turn over sod or dig down into 
 the soil from six inches to two feet. In order to 
 keep hogs from killing out pasture in which they 
 feed, rings are put into their snouts to keep them 
 from -" rooting." The sense of smell is very well 
 developed. Hogs are said to be able to follow scent 
 quite as well as a dog. The mouth opens under the 
 snout. All the different kinds of teeth are present. 
 There are six incisors, two canines and seven molars 
 on each jaw. The canine teeth in the upper jaw turn 
 upward. In the males these teeth grow quite long 
 and are called tusks. In the wild boar the tusks are 
 very large and are strong weapons of defense. 
 
 Hogs have formed the habit of wallowing in mud 
 and water for two reasons. One is that they do not 
 perspire as some other animals do, and to keep cool 
 they lie down in water and mud. The other reason 
 
DOMESTIC ANIMALS 
 
 313 
 
 if; 
 
 is that the hair on their bodies is so scattered that 
 flies and other insects have easy access to the skin. 
 They get into the mud and water to protect themselves 
 from insect pests. 
 
 Breeds of hogs. There are a number of different 
 breeds in the United States, most of which have been 
 developed here. The favorite black breeds are the 
 Berkshire and the Poland-China, Both are black with 
 white spots or bands 
 over the body. The 
 Berkshire has erect 
 ears, while those of 
 the Poland- China are 
 drooping. They are 
 both rapid growers. 
 
 The most favored Fi S- 62 - Poland China, a lard type 
 
 of hog. 
 
 white breed is known 
 
 as the Chester White. Hogs of this breed are some- 
 what slow maturing but are hardy. 
 
 The Duroc-Jersey is of a reddish brown color. It 
 has a large frame and is easily raised. It is becom- 
 ing a great favorite in many parts of the Middle 
 West. 
 
 All of the breeds named thus far belong to the 
 lard or fat type. There is another class of hogs 
 known as the bacon type. 
 
 The fat hog has a thick, deep body, strong hams, 
 
314 
 
 STUDIES IN SCIENCE 
 
 short head, and short legs. The bacon hog is not 
 as broad as the fat hog, and has longer sides, lighter 
 hams, and longer legs. Throughout the corn belt the 
 fat type is raised almost exclusively. Farther north 
 some of the bacon types are raised. In some parts 
 of the East and in Canada the bacon type is more 
 
 Fig. 63. Large Yorkshire, a bacon type of hog. 
 
 common than . the fat hog. Among the best known 
 bacon hogs are the Essex, the Hampshire and the 
 Tamworths. 
 
 Care of hogs. How are hogs cared for in your 
 neighborhood? How are they housed? Describe any 
 hog houses that you have seen. 
 
DOMESTIC ANIMALS 315 
 
 Farmers are everywhere giving more attention to 
 the care of their hogs. Formerly any place was 
 thought good enough for these animals. Now, good 
 houses that will admit plenty of sunshine and air 
 are finding favor. These houses are constructed so 
 that the hogs may have a warm, dry shelter during the 
 winter and cool spring months. The most approved 
 houses are long buildings facing the south, and 
 divided into pens from five to eight feet wide and 
 
 Fig. 64. A good hog house. 
 
 from eight to twelve feet long. From each pen there 
 is a door leading to an outside run. The floors are 
 usually cement, although some are of wood. Troughs 
 for semi-liquid food and for water are placed along 
 the sides of the pens. 
 
 Food for hogs. While pigs are young they should 
 be fed milk and a little ground feed such as shorts. 
 Later, especially when they no longer depend upon 
 
316 STUDIES IN SCIENCE 
 
 their mother's milk, they should be fed milk and 
 ground feeds with a little dry grain such as oats, 
 and if possible they should be allowed to run on 
 pasture. At this stage in their lives, when they are 
 growing rapidly, pasturage and other succulent 
 foods are excellent for them. When they are from 
 six to seven months old they are ready to fatten. 
 They should now be fed much more corn and should 
 no longer be allowed to run in the pasture. Some 
 tests show that alfalfa fed with corn gives excellent 
 results. 
 
 Diseases. Hogs, more than any other domestic 
 animals, are subject to a p.umber of diseases. The 
 one most dreaded is cholera. It frequently kills off 
 an entire herd within a few weeks. This disease is 
 due to bacteria and is very contagious. The bacteria 
 may be carried by animals that go from one farm to 
 another as dogs, cats, pigeons and other birds that 
 feed in the hog lot. Men may carry them on their 
 shoes as they walk about in soil and debris. When- 
 ever cholera is in the neighborhood, the greatest care 
 should be taken to prevent its spreading. The most 
 effective means now used to prevent the disease is 
 vaccination. A serum is injected into the blood of 
 all well hogs which acts in much the same way that 
 anti-toxin acts to prevent diphtheria. If it is sue- 
 
DOMESTIC ANIMALS 317 
 
 cessful, the hogs are immune from the disease for a 
 number of months. 
 
 Value of hogs. How valuable are hogs to the 
 average farmer? What are they worth? What is a 
 good average weight when the hog is ready for 
 market? 
 
 When managed properly hogs bring excellent 
 returns to the farmer. The price varies from time 
 to time as with every other farm commodity. It is 
 usually quoted at so much per hundred pounds. It 
 has sometimes been as low as four dollars per hun- 
 dred, but often reaches six, eight and even twelve 
 dollars. Recently hogs have sold on foot as high as 
 twenty dollars a hundred. A good average weight 
 of fat hogs from seven to nine months of age is from 
 two hundred and fifty to two hundred and seventy- 
 five pounds. Older hogs weigh from three to five hun- 
 dred pounds. 
 
 Booklets and charts. Make a collection of pictures 
 showing different breeds of hogs, hog houses, hog 
 cots, etc. Paste these on sheets of heavy paper and 
 label carefully. 
 
 Project. No other farm animal lends itself so 
 readily to boys' and girls ' projects as a pig. Procure 
 a pig a few months old. Feed it till ready for market. 
 Keep a record of feed, other expenses, weight gained, 
 and profits. 
 
318 STUDIES IN SCIENCE 
 
 j, 
 
 4. SHEEP 
 
 Material. Sheep of the neighborhood. A portion 
 of a fleece. Pictures of sheep. 
 
 The sheep as a type of animal. Make a study of 
 a sheep. Note all the parts and describe each. If you 
 do not have access to a living sheep procure some 
 good pictures and study those.* Note the shape of 
 the body, the length of the legs, the thickness of the 
 legs, the position and manner of holding the ears, 
 the shape and color of the nose, and the size and 
 appearance of the eye. Study the woolly coat, its 
 color, thickness, difference between outer and inner 
 portions, variations on different parts of the body. 
 
 Note the difference in appearance between the male 
 and female sheep. The males are known as rams, 
 the female are ewes. 
 
 Study a lamb comparing with the adult. 
 
 What do sheep eat! "What other domestic animals 
 do they resemble in their habits of eating! 
 
 How many farmers in your community keep sheep! 
 What different breeds are represented! For what 
 purpose are they raised! How old are the sheep 
 when marketed for mutton ! At what season are 
 sheep sheared! How is it done! What is done with 
 the wool! How much wool will one sheep produce 
 at one shearing! 
 
 *Look in a large dictionary for pictures of types of sheep. 
 
DOMESTIC ANIMALS 319 
 
 History. Sheep are among the oldest domes- 
 tic animals. As far back as we can go in written 
 history we find sheep mentioned. The exact origin 
 of our domestic sheep is not definitely known. 
 It is thought that they originated from wild sheep 
 of Asia and Europe. Some believe that the European 
 breeds have been developed largely from small wild 
 sheep which even yet inhabit the mountains of 
 Greece, and the islands of Crete, Cypress and Cor- 
 sica. Our American breeds have been introduced 
 from Europe. 
 
 Discussion. In their wild state sheep fed upon the 
 scant plant life found in mountainous regions. For 
 that reason the domestic animals are able to subsist 
 where cattle and horses would almost starve. They 
 eat all sorts of weeds as well as grain and clovers. 
 In the woods they eat young trees and shrubs and all 
 kinds of undergrowth. 
 
 The arrangement of the teeth is similar to that of 
 the cow. There are eight incisors on the lower jaw, 
 but there are no upper front teeth. There are six 
 back teeth or molars on each half jaw. The small 
 sharp pointed front teeth enable sheep to crop very 
 small plants close to the ground. 
 
 In feeding habits sheep resemble cattle; that is, 
 they eat rapidly swallowing the food with little chew- 
 ing. Later they bring the food in small lumps back 
 
320 STUDIES IN SCIENCE 
 
 to the mouth and chew it as they lie in the shade 
 or stand together resting. As in the case of cattle, 
 this process is called chewing the cud. 
 
 Sheep can readily climb hillsides and the rugged 
 surfaces of mountainous regions. Their thick coat 
 of wool makes it possible for them to live comfortably 
 in cold regions and in high elevations. 
 
 Their native homes probably account for the well 
 developed muscles in the legs which enable them to 
 jump over crags and across ravines. The foot below 
 the ankle joint is small and delicate. It has two 
 toes upon which the animal walks. If you look 
 closely you find small, rudimentary toes above and 
 to the back of the front toes. The hoofs are kept 
 oiled by a small gland that lies between the toes. 
 
 If you observed a lamb you noticed that its legs 
 are very long compared to the size of the body. For 
 this reason a very young lamb can walk almost as 
 far during the day as the older members of the flock. 
 Lambs are very active, skipping, jumping, and play- 
 ing constantly with each other. 
 
 Lambs have quite long tails but these are cut off 
 while the lambs are young. This is to prevent burs 
 and filth from collecting on them and producing 
 disease. 
 
 Types of sheep. We have two distinct breeds of 
 sheep ; those that are raised chiefly for their wool, and 
 
DOMESTIC ANIMALS 321 
 
 those that are raised for their meat. They are known 
 as the wool type and mutton type. 
 
 The wool type is represented by the following 
 breeds: Merino, Delaine Merino and Rambouillet. 
 Their bodies are angular and thin; the skin is often 
 wrinkled so as to form folds. The build of the body 
 gives a large surface for the attachment of wool. 
 The wool itself is of a superior quality. 
 
 Sheep of the mutton type have rectangular bodies 
 built somewhat on the plan of beef cattle, so that 
 they produce a large amount of mutton. They are 
 divided into two classes, those that have wool of 
 medium length and those that have long wool. The 
 most common of the former are the Southdown, 
 Oxford and Dorset; of the latter, Cotswold, Leicester, 
 and Lincolns. 
 
 Care of sheep. Of all domestic animals sheep are 
 the most easily cared for. Their feeding habits enable 
 them to clean up fields where other animals can no 
 longer find sufficient food. They thrive best on a 
 mixture of hay, oats, some corn and silage. If they 
 are being fattened for market they are fed more grain 
 and less roughage. Lambs may be ready to put on 
 the market at from seven to twelve months of age. 
 
 Some sheep raisers make quite a profit by fattening 
 young lambs and selling them at from six to ten 
 
322 STUDIES IN SCIENCE 
 
 weeks old. Their meat is considered very choice and 
 brings a high price. 
 
 Because of the warm coat, sheep require less shelter 
 than other animals during the winter. An open shed 
 may be used. It is quite essential, however, that it 
 be kept perfectly dry. 
 
 Sheep that are kept for producing wool are sheared 
 in the spring. A good Merino fleece weighs from 
 twelve to twenty pounds. Some of the mutton breeds 
 do not yield more than eight pounds of wool. The 
 wool of the Merinos is used for the finest grade of 
 wool cloth. The mutton breeds produce a coarser 
 wool and the cloth made from this is usually of a 
 rougher weave. 
 
 A good fleece should be thick and even over the 
 whole body. It should have a strong well-crimped 
 fiber of bright appearance, and should contain enough 
 oil to preserve and keep the fiber strong. 
 
 It is said that a farmer who knows how to manage 
 his flock can make the wool pay for the feed, leaving 
 the lambs raised as clear profit. Lambs are usually 
 sold in the fall so they will not have to be sheltered 
 and fed over winter. 
 
 Wool. Study a piece of wool taken from a sheep. 
 How does it differ from hair? If possible examine it 
 with a hand lens. How does wool cloth feel? Com- 
 pare with cotton and silk. 
 
DOMESTIC ANIMALS 321 
 
 those that are raised for their meat. They are known 
 as the wool type and mutton type. 
 
 The wool type is represented by the following 
 breeds: Merino, Delaine Merino and Rambouillet. 
 Their bodies are angular and thin; the skin is often 
 wrinkled so as to form folds. The build of the body 
 gives a large surface for the attachment of wool. 
 The wool itself is of a superior quality. .. 
 
 Sheep of the mutton type have rectangular bodies 
 built somewhat on the plan of beef cattle, so that 
 they produce a large amount of mutton. They are 
 divided into two classes, those that have wool of 
 medium length and those that have long wool. The 
 most common of the former are the Southdown, 
 Oxford and Dorset; of the latter, Cotswold, Leicester, 
 and Lincolns. 
 
 Care of sheep. Of all domestic animals sheep are 
 the most easily cared for. Their feeding habits enable 
 them to clean up fields where other animals can no 
 longer find sufficient food. They thrive best on a 
 mixture of hay, oats, some corn and silage. If they 
 are being fattened for market they are fed more grain 
 and less roughage. Lambs may be ready to put on 
 the market at from seven to twelve months of age. 
 
 Some sheep raisers make quite a profit by fattening 
 young lambs and selling them at from six to ten 
 
322 STUDIES IN SCIENCE 
 
 weeks old. Their meat is considered very choice and 
 brings a high price. 
 
 Because of the warm coat, sheep require less shelter 
 than other animals during the winter. An open shed 
 may be used. It is quite essential, however, that it 
 be kept perfectly dry. 
 
 Sheep that are kept for producing wool are sheared 
 in the spring. A good Merino fleece weighs from 
 twelve to twenty pounds. Some of the mutton breeds 
 do not yield more than eight pounds of wool. The 
 wool of the Merinos is used for the finest grade of 
 wool cloth. The mutton breeds produce a coarser 
 wool and the cloth made from this is usually of a 
 rougher weave. 
 
 A good fleece should be thick and even over the 
 whole body. It should have a strong well-crimped 
 fiber of bright appearance, and should contain enough 
 oil to preserve and keep the fiber strong. 
 
 It is said that a farmer who knows how to manage 
 his flock can make the wool pay for the feed, leaving 
 the lambs raised as clear profit. Lambs are usually 
 sold in the fall so they will not have to be sheltered 
 and fed over winter. 
 
 Wool. Study a piece of wool taken from a sheep. 
 How does it differ from hair! If possible examine it 
 with a hand lens. How does wool cloth feel? Com- 
 pare with cotton and silk. 
 
DOMESTIC ANIMALS 323 
 
 Wool fibers have little scales or projections along 
 the sides, while a hair is smooth. These scales make 
 wool feel rough against the skin. 
 
 Make a list of all the things you know that are 
 made of wool. 
 
 Sheep industry. Sheep raising is not as great an 
 industry in United States as that of swine. Farmers 
 are beginning to realize, however, that a flock of sheep 
 on the farm is a paying investment. The eastern 
 states and those of the Middle West for the most part 
 raise the mutton types. In the far West more 
 Merino sheep are raised. Here are great ranches 
 where several thousands of sheep may be found in 
 one flock. In the Summer the herders with their 
 faithful shepherd dogs take the flocks to the moun- 
 tains and hillsides where they feed upon the scant 
 vegetation. In the winter they are brought down 
 to the valley where they are sheltered and fed. 
 
 Projects. The raising of lambs either for meat or 
 wool production is a project well worth undertaking 
 by any boy or girl who lives in a region where sheep 
 are raised. 
 
 Choose for the project one or more spring lambs 
 and care for them until ready to market for mutton, 
 which will be from six to eight months. Keep a 
 record of expenses; cost of feed, labor, receipts, and 
 profits. 
 
324 STUDIES IN SCIENCE 
 
 Instead of selling the sheep for mutton you may 
 keep them for their wool and to produce lambs. 
 
 Keep a record of your expenses, receipts and 
 profits. Take into account the value of the sheep and 
 lambs produced. 
 
DOMESTIC ANIMALS 323 
 
 Wool fibers have little scales or projections along 
 the sides, while a hair is smooth. These scales make 
 wool feel rough against the skin. 
 
 Make a list of all the things you know that are 
 made of wool. 
 
 Sheep industry. Sheep raising is not as great an 
 industry in United States as that of swine. Farmers 
 are beginning to realize, however, that a flock of sheep 
 on the farm is a paying investment. The eastern 
 stages and those of the Middle West for the most part 
 raise the mutton types. In the far West more 
 Merino sheep are raised. Here are great ranches 
 where several thousands of sheep may be found in 
 one flock. In the summer the herders with their 
 faithful shepherd dogs take the flocks to the moun- 
 tains and hillsides where they feed upon the scant 
 vegetation. In the winter they are brought down 
 to the valley where they are sheltered and fed. 
 
 Projects. The raising of lambs either for meat or 
 wool production is a project well worth undertaking 
 by any boy or girl who lives in a region where sheep 
 are raised. 
 
 Choose for the project one or more spring lambs 
 and care for them until ready to market for mutton, 
 which will be from six to eight months. Keep a 
 record of expenses; cost of feed, labor, receipts, and 
 profits. 
 
324 STUDIES IN SCIENCE 
 
 Instead of selling the sheep for mutton you may 
 keep them for their wool and to produce lambs. 
 
 Keep a record of your expenses, receipts and 
 profits. Take into account the value of the sheep and 
 lambs produced. 
 
WINTER STUDIES 
 
 CHAPTER XIX 
 
 LIGHT AND LIGHTING 
 
 Materials. An ordinary candle, several small 
 Christmas candles, kerosene lamp, gas fixture, elec- 
 tric light bulb, test tube, rubber stopper, glass tube, 
 small pieces of soft coal. 
 
 Study. What method of artificial lighting is used 
 in your home? In your school building ? Make a list 
 of all the different methods of lighting that you know. 
 Group them into two classes: 1. Those in which the 
 light is directly produced by a flame. 2. Those that 
 produce light in some other way. 
 
 The candle. Study a candle that has not been 
 used. Of what is it made! Examine the wick and 
 describe it. What is the shape of the candle at the 
 top? At the bottom? How was it made? Light a 
 small piece of candle. Watch very carefully to see 
 what happens till the flame remains steady. After 
 it has burned a short time notice the top of the candle. 
 What is in the hollow cup? What forms the sides 
 of the cup? How close to the cup does the flame 
 
 325 
 
326 STUDIES IN SCIENCE 
 
 extend! How high is the flame! Describe its shape. 
 Where is it widest! Where narrowest! What dif- 
 ferent colors do you see in it! How does it look at 
 the center! Make a drawing to show all the parts you 
 have observed. 
 
 Experiment. What produces the candle flame! 
 
 When your candle has been burning for some min- 
 utes blow out the flame. What do you see coming 
 from the end of the wick! What color is the smoke! 
 What do you think this smoke is! Examine the 
 warm wick and determine what is in it. Explain the 
 relation between the melted paraffin in the wick and 
 the smoke or vapor coming from it. 
 
 Relight the candle and allow it to burn for a minute 
 or two, then blow out the flame. Have a lighted 
 match ready and the moment the flame is out apply 
 the match to the smoke. Describe what happens. 
 Try this again and again till you make up your mind 
 what it is that really burns and makes the flame. 
 
 Experiment. Will liquid paraffin burn! If you 
 are not quite certain whether it is the melted paraffin 
 or the vapor of paraffin that burns, make this experi- 
 ment. Melt a little paraffin in a tin cup or deep 
 spoon. Apply a lighted match to see if it will burn. 
 How many different forms of paraffin are present in 
 the burning candle! What besides the paraffin vapor 
 is needed to make the candle flame! 
 
WINTER STUDIES 
 
 CHAPTER XIX 
 
 LIGHT AND LIGHTING 
 
 Materials. An ordinary candle, several small 
 Christmas candles, kerosene lamp, gas fixture, elec- 
 tric light bulb, test tube, rubber stopper, glass tube, 
 small pieces of soft coal. 
 
 Study. What method of artificial lighting is used 
 in your home? In your school building? Make a list 
 of all the different methods of lighting that you know. 
 Group them into two classes: 1. Those in which the 
 light is directly produced by a flame. 2. Those that 
 produce light in some other way. 
 
 The candle. Study a candle that has not been 
 used. Of what is it made? Examine the wick and 
 describe it. What is the shape of the candle at the 
 top? At the bottom? How was it made? Light a 
 small piece of candle. Watch very carefully to see 
 what happens till the flame remains steady. After 
 it has burned a short time notice the top of the candle. 
 What is in the hollow cup? What forms the sides 
 of the cup? How close to the cup does the flame 
 
 325 
 
326 STUDIES IN SCIENCE 
 
 extend? How high is the flame? Describe its shape. 
 Where is it widest! Where narrowest? What dif- 
 ferent colors do you see in it? How does it look at 
 the center? Make a drawing to show all the parts you 
 have observed. 
 
 Experiment. What produces the candle flame? 
 
 When your candle has been burning for some min- 
 utes blow out the flame. What do you see coming 
 from the end of the wick? What color is the smoke? 
 What do you think this smoke is? Examine the 
 warm wick and determine what is in it. Explain the 
 relation between the melted paraffin in the wick and 
 the smoke or vapor coming from it. 
 
 Eelight the candle and allow it to burn for a minute 
 or two, then blow out the flame. Have a lighted 
 match ready and the moment the flame is out apply 
 the match to the smoke. Describe what happens. 
 Try this again and again till you make up your mind 
 what it is that really burns and makes the flame. 
 
 Experiment. Will liquid paraffin burn? If you 
 are not quite certain whether it is the melted paraffin 
 or the vapor of paraffin that burns, make this experi- 
 ment. Melt a little paraffin in a tin cup or deep 
 spoon. Apply a lighted match to see if it will burn. 
 How many different forms of paraffin are present in 
 the burning candle? What besides the paraffin vapor 
 is needed to make the candle flame? 
 
LIGHT AND LIGHTING 327 
 
 Explanation. When you lit the candle the heat 
 of the match melted the paraffin or tallow in the 
 upper part of the wick and a small part of the liquid 
 changed to vapor and began to burn. The heat from 
 this melted more paraffin and more vapor was formed. 
 Presently there was sufficient heat to melt the paraffin 
 around the wick and form a cup at the top of the 
 candle. The liquid paraffin was absorbed by the 
 wick, was changed to vapor at the top and burned. 
 This explains why the flame is small at first but 
 gradually increases in size till there is a steady sup- 
 ply of vapor at the top of the wick. 
 
 You noticed that the burning seems to take place 
 along the outer portion of the flame. The inner dark 
 portion is the paraffin vapor or gas that is not burning. 
 You have already discovered that air is necessary 
 for burning to take place, so it is easy to see why the 
 burning is at the outer portion where there is a con- 
 stant supply of fresh air. 
 
 Experiment. What is meant by candle power? 
 Darken the room as much as possible. Light an ordi- 
 nary candle and place it on a table. On the same 
 table about two feet from the first candle place a 
 lighted Christmas candle. When both are burning 
 brightly open a book on the table about half way 
 between the two lights, and begin to read. When you 
 have read about a minute have some one extinguish 
 
328 STUDIES IN SCIENCE 
 
 the flame of the larger candle. Continue to read. 
 Have the person relight the larger candle and after 
 a few moments extinguish the flame of the small 
 one. What difference do you notice as to the strength 
 of the light from the two candles? 
 
 Candle power. You often hear people speak of the 
 candle power of different kinds of light. The electric 
 lights used in our homes are commonly 8 or 16 candle 
 power. A standard candle is used to measure the 
 intensity of light. Your simple experiment with the 
 two candles proved that there is a great difference 
 in the intensity of light given out by different lighted 
 bodies. Scientists by careful measurements decided 
 on a standard with which to measure the illuminating 
 power of artificial light. One candle power is the 
 amount of light emitted by a sperm candle seven- 
 eighths of an inch in diameter and burning 120 grains 
 of sperm oil per hour. 
 
 Lights used in early times. Before the candle came 
 into use, a very crude form of lamp was used for 
 lighting. This consisted of a vessel containing melted 
 fat, into which a piece of twisted cloth was thrust 
 for a wick. This primitive lamp was really the fore- 
 runner of the candle. In the early pioneer days of 
 our country, before primitive lamps and candles came 
 into use, homes were lighted by pine knots or by the 
 light which came from the fireplace. 
 
LIGHT AND LIGHTING 327 
 
 Explanation. When you lit the candle the heat 
 of the match melted the paraffin or tallow in the 
 upper part of the wick and a small part of the liquid 
 changed to vapor and began to burn. The heat from 
 this melted more paraffin and more vapor was formed. 
 Presently there was sufficient heat to melt the paraffin 
 around the wick and form a cup at the top of the 
 candle. The liquid paraffin was absorbed by the 
 wick, was changed to vapor at the top and burned. 
 This explains why the flame is small at first but 
 gradually increases in size till there is a steady sup- 
 ply of vapor at the top of the wick. 
 
 You noticed that the burning seems to take place 
 along the outer portion of the flame. The inner dark 
 portion is the paraffin vapor or gas that is not burning. 
 You have already discovered that air is necessary 
 for burning to take place, so it is easy to see why the 
 burning is at the outer portion where there is a con- 
 stant supply of fresh air. 
 
 Experiment. "What is meant by candle power? 
 Darken the room as much as possible. Light an ordi- 
 nary candle and place it on a table. On the same 
 table about two feet from the first candle place a 
 lighted Christmas candle. When both are burning 
 brightly open a book on the table about half way 
 between the two lights, and begin to read. When you 
 have read about a minute have some one extinguish 
 
328 STUDIES IN SCIENCE 
 
 the flame of the larger candle. Continue to read. 
 Have the person relight the larger candle and after 
 a few moments extinguish the flame of the small 
 one. What difference do you notice as to the strength 
 of the light from the two candles! 
 
 Candle power. You often hear people speak of the 
 candle power of different kinds of light. The electric 
 lights used in our homes are commonly 8 or 16 candle 
 power. A standard candle is used to measure the 
 intensity of light. Your simple experiment with the 
 two candles proved that there is a great difference 
 in the intensity of light given out by different lighted 
 bodies. Scientists by careful measurements decided 
 on a standard with which to measure the illuminating 
 power of artificial light. One candle power is the 
 amount of light emitted by a sperm candle seven- 
 eighths of an inch in diameter and burning 120 grains 
 of sperm oil per hour. 
 
 Lights used in early times. Before the candle came 
 into use, a very crude form of lamp was used for 
 lighting. This consisted of a vessel containing melted 
 fat, into which a piece of twisted cloth was thrust 
 for a wick. This primitive lamp was really the fore- 
 runner of the candle. In the early pioneer days of 
 our country, before primitive lamps and candles came 
 into use, homes were lighted by pine knots or by the 
 light which came from the fireplace. 
 
LIGHT AND LIGHTING 329 
 
 At first candles were made by a process called 
 dipping. Tallow was melted in a large iron kettle. 
 Strings, sometimes as many as a dozen at once, were 
 tied to sticks a foot or two in length and dipped into 
 the hot tallow. Then they were taken out, hung up 
 a few minutes until the tallow hardened, when they 
 were dipped again for a moment. This process was 
 repeated again and again till the candles were of the 
 necessary size. You can imagine how much time was 
 required to dip enough candles to last the family 
 for a whole year. 
 
 After a time candles were made by molding. I 
 wonder if any of you may have in your home an old 
 set of candle molds? The molds were first strung 
 with the wicking, then the melted tallow was poured 
 in. The candles we use today are made in molds 
 but the work is done in factories instead of at home. 
 Most candles we have today are made of paraffin 
 instead of tallow. 
 
 Paraffin is made from crude petroleum or crude oil. 
 It melts at a high temperature. When the candle is 
 burning the heat from it melts the paraffin around 
 the wick. This is changed to vapor or gas at the 
 top of the wick; so you- have in a burning candle an 
 excellent example of the three forms in which matter 
 of any kind may exist; solid, liquid, and gas. 
 
 The kerosene lamp. Study a kerosene lamp which 
 
330 STUDIES IN SCIENCE 
 
 is about half full of kerosene. Write the names of 
 all the parts and try to determine the use of each. 
 What is in the bowl? In the upper part of the wick? 
 Light the lamp and compare the flame with that of 
 the candle. 
 
 Experiment. To determine the use of the chim- 
 ney. Light the lamp and put the chimney in place. 
 Watch the flame to determine whether or not it is 
 steady. Extinguish the flame and remove the chim- 
 ney. Eelight the lamp. Try this several times, in 
 a draft and in quiet air, till you are certain that the 
 chimney has a special use. 
 
 Experiment. To determine what burns to produce 
 the flame. 
 
 Light the lamp and do not put on the chimney. 
 Blow out the flame as you did in the candle experi- 
 ment, and by trying to light the gas or smoke that 
 comes from the wick determine whether it is the 
 liquid kerosene or the gas that burns and makes the 
 flame. 
 
 Experiment. Look carefully at the burner to deter- 
 mine whether any provision is made for the admis- 
 sion of air to the upper part of the wick. Trace the 
 air from the outside into the chimney. To do this 
 light a small splinter of pine wood, a twisted paper 
 lighter, or a piece of punk. Allow it to burn a few 
 moments, then blow out the flame and hold it below 
 
LIGHT AND LIGHTING 329 
 
 At first candles were made by a process 
 dipping. Tallow was melted in a large iron kettle. 
 Strings, sometimes as many as a dozen at once, were 
 tied to sticks a foot or two in length and dipped into 
 the hot tallow. Then they were taken out, hung up 
 a few minutes until the tallow hardened, when they 
 were dipped again for a moment. This process was 
 repeated again and again till the candles were of the 
 necessary size. You can imagine how much time was 
 required to dip enough candles to last the family 
 for a whole year. 
 
 After a time candles were made by molding. I 
 wonder if any of you may have in your home an old 
 set of candle molds? The molds were first strung 
 with the wicking, then the melted tallow was poured 
 in. The candles we use today are made in molds 
 but the work is done in factories instead of at home. 
 Most candles we have today are made of paraffin 
 instead of tallow. 
 
 Paraffin is made from crude petroleum or crude oil. 
 It melts at a high temperature. When the candle is 
 burning the heat from it melts the paraffin around 
 the wick. This is changed to vapor or gas at the 
 top of the wick; so you have in a burning candle an 
 excellent example of the three forms in which matter 
 of any kind may exist; solid, liquid, and gas. 
 
 The kerosene lamp. Study a kerosene lamp which 
 
330 STUDIES IN SCIENCE 
 
 is about half full of kerosene. Write the names of 
 all the parts and try to determine the use of each. 
 What is in the bowl? In the upper part of the wick? 
 Light the lamp and compare the flame with that of 
 the candle. 
 
 Experiment. To determine the use of the chim- 
 ney. Light the lamp and put the chimney in place. 
 Watch the flame to determine whether or not it is 
 steady. Extinguish the flame and remove the chim- 
 ney. Eelight the lamp. Try this several times, in 
 a draft and in quiet air, till you are certain that the 
 chimney has a special use. 
 
 Experiment. To determine what burns to produce 
 the flame. 
 
 Light the lamp and do not put on the chimney. 
 Blow out the flame as you did in the candle experi- 
 ment, and by trying to light the gas or smoke that 
 comes from the wick determine whether it is the 
 liquid kerosene or the gas that burns and makes the 
 flame. 
 
 Experiment. Look carefully at the burner to deter- 
 mine whether any provision is made for the admis- 
 sion of air to the upper part of the wick. Trace the 
 air from the outside into the chimney. To do this 
 light a small splinter of pine wood, a twisted paper 
 lighter, or a piece of punk. Allow it to burn a few 
 moments, then blow out the flame and hold it below 
 
LIGHT AND LIGHTING 331 
 
 the burner. Watch to see where the smoke enters the 
 chimney. Hold the smoking splinter above the chimney 
 to determine the direction of the air currents there. 
 What causes the air to move through the base of the 
 burner toward the flame? 
 
 What is kerosene and how is to obtained? 
 
 Explanation. You probably have decided from 
 your experiments that the chimney and burner to- 
 gether regulate the amount of air that is brought to 
 the flame. The openings in the base of the burner 
 allow the cool air from below to enter and the cap 
 directs the air toward the flame. 
 
 You proved by experiment that it is the gas or 
 vapor of kerosene that burns and not the liquid. 
 The fact is that every flame in the world is produced 
 by burning gas or vapor. 
 
 Kerosene is another product of petroleum or crude 
 oil. Look in your geography to find out where the 
 great oil fields of United States are located and make 
 a list of all the uses of crude petroleum. Perhaps 
 you are near enough to a region where there are oil 
 wells to visit them and see how the oil is obtained. 
 
 Crude petroleum is .a mixture of a number of dif- 
 ferent liquids. To obtain these the petroleum is 
 heated and the liquids are changed into vapors. The 
 vapor is caught in large vessels where it condenses 
 and changes back into a liquid. The lightest liquid 
 
332 STUDIES IN SCIENCE 
 
 changes to vapor first and is caught by itself. Gas- 
 oline is lighter than kerosene, so it vaporizes first and 
 is obtained before kerosene. 
 
 The process of separating a mixture of liquids by 
 vaporization and then condensing them is called 
 distillation. 
 
 The main products distilled from petroleum are: 
 light gasoline, heavy gasoline, naphtha, kerosene, 
 vaseline and paraffin. 
 
 Gas lamp. Study an ordinary gas lamp used for 
 lighting homes. Write the names of the parts. 
 
 Light the lamp. Can you see a flame! What pro- 
 duces the light! Remove the mantle from the burner. 
 (This must be done very carefully or the mantle will 
 break.) Now turn on the gas and light it. What is 
 the color of the flame! Does it give a good light! 
 Examine the lower part of the tube which leads to 
 the flame for air openings that might admit air into 
 the tube. If you have an ordinary gas jet that does 
 not have a mantle or globe, light it. What is the 
 color of the flame! Does it have an opening in the 
 tube to admit air! What really happens when you 
 turn on the gas! Find the gas pipes and meter in 
 the basement. What is the meter for! Is the gas 
 that you use manufactured or natural ! How is manu- 
 factured gas sold! 
 
 Experiment. To generate coal gas. Procure a test 
 
LIGHT AND LIGHTING 331 
 
 the burner. Watch to see where the smoke enters the 
 chimney. Hold the smoking splinter above the chimney 
 to determine the direction of the air currents there. 
 What causes the air to move through the base of the 
 burner toward the flame? 
 
 What is kerosene and how is to obtained? 
 
 Explanation. You probably have decided from 
 your experiments that the chimney and burner to- 
 gether regulate the amount of air that is brought to 
 the flame. The openings in the base of the burner 
 allow the cool air from below to enter and the cap 
 directs the air toward the flame. 
 
 You proved by experiment that it is the gas or 
 vapor of kerosene that burns and not the liquid. 
 The fact is that every flame in the world is produced 
 by burning gas or vapor. 
 
 Kerosene is another product of petroleum or crude 
 oil. Look in your geography to find out where the 
 great oil fields of United States are located and make 
 a list of all the uses of crude petroleum. Perhaps 
 you are near enough to a region where there are oil 
 wells to visit them and see how the oil is obtained. 
 
 Crude petroleum is a mixture of a number of dif- 
 ferent liquids. To obtain these the petroleum is 
 heated and the liquids are changed into vapors. The 
 vapor is caught in large vessels where it condenses 
 and changes back into a liquid. The lightest liquid 
 
332 STUDIES IN SCIENCE 
 
 changes to vapor first, and is caught by itself. Gas- 
 oline is lighter than kerosene, so it vaporizes first and 
 is obtained before kerosene. 
 
 The process of separating a mixture of liquids by 
 vaporization and then condensing them is called 
 distillation. 
 
 The main products distilled from petroleum are: 
 light gasoline, heavy gasoline, naphtha, kerosene, 
 vaseline and paraffin. 
 
 Gas lamp. Study an ordinary gas lamp used for 
 lighting homes. Write the names of the parts. 
 
 Light the lamp. Can you see a flame? What pro- 
 duces the light ? Remove the mantle from the burner. 
 (This must be done very carefully or the mantle will 
 break.) Now turn on the gas and light it. What is 
 the color of the flame! Does it give a good light? 
 Examine the lower part of the tube which leads to 
 the flame for air openings that might admit air into 
 the tube. If you have an ordinary gas jet that does 
 not have a mantle or globe, light it. What is the 
 color of the flame? Does it have an opening in the 
 tube to admit air? What really happens when you 
 turn on the gas? Find the gas pipes and meter in 
 the basement. What is the meter for? Is the gas 
 that you use manufactured or natural ? How is manu- 
 factured gas sold? 
 
 Experiment. To generate coal gas. Procure a test 
 
LIGHT AND LIGHTING 333 
 
 tube, a rubber stopper with a hole in it, and a piece of 
 glass tubing about six inches long that fits tight in 
 the stopper. Place a piece of soft coal about the size 
 of a hickory nut in the test tube. Put in the rubber 
 stopper. Hold the test tube almost horizontally, 
 tipped slightly downward at the mouth. With an 
 alcohol lamp heat the coal. When the vapor comes 
 out of the tube light it and you have a small gas jet. 
 
 Explanation. Most gas lamps have a mantle which 
 conceals the flame. The flame is what is known as a 
 blue flame. It is veiy hot but not bright so it gives 
 a very poor light. But the mantle becomes so hot 
 that it glows with a white heat and produces a very 
 good light. With this kind of a light the air enters 
 at the air openings on the side of the tube. When 
 you turn the gas on it mixes with the air before it 
 reaches the flame. A lamp that has the air and gas 
 supply mixed in proper proportions makes a hot 
 blue flame. 
 
 In the open jet the air mixes with the gas as it 
 burns. This produces a flame similar to that of the 
 candle or kerosene lamp. It does not produce as good 
 a light as the lamp with the mantle and it burns more 
 gas. 
 
 Different kinds of gas are used for lighting pur- 
 poses. Some people have their own gas plants and 
 generate a gas out of gasoline. Others have acetylene 
 
334 STUDIES IN SCIENCE 
 
 gas machines. In some places natural gas that is 
 found far down in the earth is used. Wells are sunk 
 and the gas piped from them to buildings. Many 
 towns and cities manufacture gas from coal or other 
 materials and pipe this to homes and other buildings. 
 It flows through a meter in each house and by a 
 device the amount used is measured in cubic feet. 
 The price of gas varies in different places from eighty 
 cents to one dollar and twenty-five cents per 1,000 
 cubic feet. 
 
 Electric lights. Examine an electric light bulb. 
 What do you find? Turn on the electricity. Is there 
 any flame in the bulb! What produces the light? 
 
 Experiment. A light without a flame. Put an iron 
 poker in the stove or furnace and allow it to remain 
 until it is very hot, then take it out and hold it, 
 heated end up, in a dark room noting the light that 
 it gives out. If there were some way that you could 
 keep it white hot would it light a room fairly well? 
 Is it burning? How does it make light? 
 
 What happens when you press the button or turn 
 the electric switch? Wliere does the electricity enter 
 your home? How many wires are there? To what 
 are the wires connected inside the building? What is 
 the use of the meter? 
 
 Study the street lights in your town. Are they all 
 of the same kind? Compare with one another and 
 
LIGHT AND LIGHTING 333 
 
 tube, a rubber stopper with a hole in it, and a piece of 
 glass tubing about six inches long that fits tight in 
 the stopper. Place a piece of soft coal about the size 
 of a hickory nut in the test tube. Put in the rubber 
 stopper. Hold the test tube almost horizontally, 
 tipped slightly downward at the mouth. With an 
 alcohol lamp heat the coal. When the vapor comes 
 out of the tube light it and you have a small gas jet. 
 
 Explanation. Most gas lamps have a mantle which 
 conceals the flame. The flame is what is known as a 
 blue flame. It is veiy hot but not bright so it gives 
 a very poor light. But the mantle becomes so hot 
 that it glows with a white heat and produces a very 
 good light. With this kind of a light the air enters 
 at the air openings on the side of the tube. When 
 you turn the gas on it mixes with the air before it 
 reaches the flame. A lamp that has the air and gas 
 supply mixed in proper proportions makes a hot 
 blue flame. 
 
 In the open jet the air mixes with the gas as it 
 burns. This produces a flame similar to that of the 
 candle or kerosene lamp. It does not produce as good 
 a light as the lamp with the mantle and it burns more 
 gas. 
 
 Different kinds of gas are used for lighting pur- 
 poses. Some people have their own gas plants and 
 generate a gas out of gasoline. Others have acetylene 
 
334 STUDIES IN SCIENCE 
 
 gas machines. In some places natural gas that is 
 found far down in the earth is used. Wells are sunk 
 and the gas piped from them to buildings. Many 
 towns and cities manufacture gas from coal or other 
 materials and pipe this to homes and other buildings. 
 It flows through a meter in each house and by a 
 device the amount used is measured in cubic feet. 
 The price of gas varies in different places from eighty 
 cents to one dollar and twenty-five cents per 1,000 
 cubic feet. 
 
 Electric lights. Examine an electric light bulb. 
 What do you find? Turn on the electricity. Is there 
 any flame in the bulb? What produces the light? 
 
 Experiment. A light without a flame. Put an iron 
 poker in the stove or furnace and allow it to remain 
 until it is very hot, then take it out and hold it, 
 heated end up, in a dark room noting the light that 
 it gives out. If there were some way that you could 
 keep it white hot would it light a room fairly well? 
 Is it burning? How does it make light? 
 
 What happens when you press the button or turn 
 the electric switch? Where does the electricity enter 
 your home? How many wires are there? To what 
 are the wires connected inside the building? What is 
 the use of the meter? 
 
 Study the street lights in your town. Are they all 
 of the same kind? Compare with one another and 
 
LIGHT AND LIGHTING 335 
 
 with those used in your home or other buildings. In 
 each case determine the route by which the electri- 
 city gets from the power house to the lamp. 
 
 Explanation. In cities, and even in some rural 
 districts, electric lights are fast taking the place of 
 all other kinds because* they are most convenient and 
 give the best light in proportion to the cost. 
 
 You observed that the light in the bulb is made by 
 a fine wire, which becomes very hot and glows just as 
 the end of the poker did in your experiment. When 
 you press the button you cause a current of electricity 
 to flow through the wire in the lamp, and this causes 
 the wire to become hot. There is no burning con- 
 nected with it. When a body is heated to a white 
 heat, it is said to be heated to incandescence; so this 
 kind of electric light is called an incandescent light. 
 
 The electricity is generated in the power house 
 and flows along wires in the street or ground known 
 as line wires. Other wires extend from these to the 
 buildings. When you press the button you simply 
 connect the line wire with the lamps so that the 
 current may flow through it. Electricity flows more 
 readily through copper than through other metals. 
 The finer the wire the more resistance is offered to 
 the current. Line wires are made of rather large 
 copper wire. The incandescent lamp has either a very 
 fine carbon or tungsten filament which offers such a 
 
336 
 
 STUDIES IN SCIENCE 
 
 great resistance to the current that it becomes very 
 hot and thus gives light. Tungsten is coming into 
 use more and more since, with the same strength of 
 electricity, it gives almost three times as intense a 
 light as the carbon. It is more expensive, but because 
 of its greater efficiency it is more economical in the 
 long run. 
 
 EYES 
 
 Look into a mirror and note all the different parts 
 of your eye. Look at an eye of one of your class- 
 mates. 
 
 . Sclerotic 
 
 Choroid 
 
 Aqueous 
 humor 
 
 Fig. 65. Section of the eye. 
 
 The parts that you can see are: (1) The eyelids 
 with their lashes. These ate to protect the eye from 
 dust and other foreign objects. (2) A small part of 
 
LIGHT AND LIGHTING 335 
 
 with those used in your home or other buildings. In 
 each case determine the route by which the electri- 
 city gets from the power house to the lamp. 
 
 Explanation. In cities, and even in some rural 
 districts, electric lights are fast taking the place of 
 all other kinds because they are most convenient and 
 give the best light in proportion to the cost. 
 
 You observed that the light in the bulb is made by 
 a fine wire, which becomes very hot and glows just as 
 the end of the poker did in your experiment. When 
 you press the button you cause a current of electricity 
 to flow through the wire in the lamp, and this causes 
 the wire to become hot. There is no burning con- 
 nected with it. When a body is heated to a white 
 heat, it is said to be heated to incandescence; so this 
 kind of electric light is called an incandescent light. 
 
 The electricity is generated in the power house 
 and flows along wires in the street or ground known 
 as line wires. Other wires extend from these to the 
 buildings. When you press the button you simply 
 connect the line wire with the lamps so that the 
 current may flow through it. Electricity flows more 
 readily through copper than through other metals. 
 The finer the wire the more resistance is offered to 
 the current. Line wires are made of rather large 
 copper wire. The incandescent lamp has either a very 
 fine carbon or tungsten filament which offers such a 
 
336 
 
 STUDIES IN SCIENCE 
 
 great resistance to the current that it becomes very 
 hot and thus gives light. Tungsten is coming into 
 use more and more since, with the same strength of 
 electricity, it gives almost three times as intense a 
 light as the carbon. It is more expensive, but because 
 of its greater efficiency it is more economical in the 
 long run. 
 
 EYES 
 
 Look into a mirror and note all the different parts 
 of your eye. Look at an eye of one of your class- 
 mates. 
 
 Sclerotic 
 
 Choroid 
 
 Optic Nerve 
 
 Aqueous 
 humor 
 
 Fig. 65. Section of the eye. 
 
 The parts that you can see are: (1) The eyelids 
 with their lashes. These aie to protect the eye from 
 dust and other foreign objects. (2) A small part of 
 
LIGHT AND LIGHTING 337 
 
 the eyeball with the white covering. (3) In front you 
 see the colored part of the eye known as the iris. 
 In the center of this is the dark round spot called the 
 pupil. The iris and pupil are covered with a trans- 
 parent covering called the cornea. If you could see 
 your entire eye you would find that the ball fills a 
 bony socket which you can feel surrounding the eye. 
 On the inside of the ball back of the iris is a little 
 watery fluid and back of this is a lens known as the 
 crystalline lens. The rest of the ball is filled with a 
 semi-liquid substance somewhat clearer than the white 
 of an egg called vitreous humor. On the inside of 
 the wall next to the white coat is a dark coat and 
 inside of this is the retina, which is really the spread 
 out optic nerve. 
 
 Bays of light pass from any object you are looking' 
 at through the pupil, then through the lens and an 
 image of the object is thrown upon the retina. This 
 in some way stimulates the optic nerve which carries 
 the sensation to the brain and thus you see the object. 
 The plates or film of a camera receive picture impres- 
 sions in much the same way that the retina does. 
 
 Care of the eyes. Eyes are such delicate yet won- 
 derful devices for seeing that they should receive the 
 greatest care. They may be permanently injured by 
 using them in a bad light. People everywhere are 
 giving more attention to the proper lighting of homes, 
 
338 STUDIES IN SCIENCE 
 
 schools, libraries and other buildings. Light that 
 comes from above is better than light that is on a 
 level with the eyes. Window shades in many schools 
 are adjusted so that the lower part of the window 
 may be covered with the shade while the upper por- 
 tion admits the light. 
 
 The light from an ordinary kerosene lamp, gas jet, 
 or clear glass electric bulb is called direct light. If 
 the direct rays are broken up by reflection from an 
 uneven surface, as a papered wall or ceiling, or by 
 passing through white or frosted globes or window 
 cu^ains, the light is diffused. Diffused light is much 
 
 for the eyes than direct light. 
 >tudy the lighting arrangements in your home and 
 school. Decide which kind of light you are using. 
 
 Placing a shade over an ordinary lamp will aid 
 greatly in softening and diffusing the rays. In using 
 any artificial or natural light sit so that the light 
 will strike your work over the left shoulder. Beading 
 while lying down causes a great strain upon the eyes. 
 
 Whenever there are any indications that something 
 is wrong with the eyes, an oculist should be consulted 
 at once. In many schools children's eyes are tested 
 once each year. Many really bright pupils are con- 
 sidered dull simply because their eyesight is defec- 
 tive and they cannot see well enough to do their 
 work properly. 
 
LIGHT AND LIGHTING 337 
 
 the eyeball with the white covering. (3) In front you 
 see the colored part of the eye known as the iris. 
 In the center of this is the dark round spot called the 
 pupil. The iris and pupil are covered with a trans- 
 parent covering called the cornea. If you could see 
 your entire eye you would find that the ball fills a 
 bony socket which you can feel surrounding the eye. 
 On the inside of the ball back of the iris is a little 
 watery fluid and back of this is a lens known as the 
 crystalline lens. The rest of the ball is filled with a 
 semi-liquid substance somewhat clearer than the white 
 of an egg called vitreous humor. On the inside of 
 the wall next to the white coat is a dark coat and 
 inside of this is the retina, which is really the spread 
 out optic nerve. 
 
 Eays of light pass from any object you are looking' 
 at through the pupil, then through the lens and an 
 image of the object is thrown upon the retina. This 
 in some way stimulates the optic nerve which carries 
 the sensation to the brain and thus you see the object. 
 The plates or film of a camera receive picture impres- 
 sions in much the same way that the retina does. 
 
 Care of the eyes. Eyes are such delicate yet won- 
 derful devices for seeing that they should receive the 
 greatest care. They may be permanently injured by 
 using them in a bad light. People everywhere are 
 giving more attention to the proper lighting of homes, 
 
338 STUDIES IN SCIENCE 
 
 schools, libraries and other buildings. Light that 
 comes from above is better than light that is on a 
 level with the eyes. Window shades in many schools 
 are adjusted so that the lower part of the window 
 may be covered with the shade while the upper por- 
 tion admits the light. 
 
 The light from an ordinary kerosene lamp, gas jet, 
 or clear glass electric bulb is called direct light. If 
 the direct rays are broken up by reflection from an 
 uneven surface, as a papered wall or ceiling, or by 
 passing through white or frosted globes or window 
 curtains, the light is diffused. Diffused light is much 
 better for the eyes than direct light. 
 
 Study the lighting arrangements in your home and 
 school. Decide which kind of light you are using. 
 
 Placing a shade over an ordinary lamp will aid 
 greatly in softening and diffusing the rays. In using 
 any artificial or natural light sit so that the light 
 will strike your work over the left shoulder. Reading 
 while lying down causes a great strain upon the eyes. 
 
 Whenever there are any indications that something 
 is wrong with the eyes, an oculist should be consulted 
 at once. In many schools children's eyes are tested 
 once each year. Many really bright pupils are con- 
 sidered dull simply because their eyesight is defec- 
 tive and they cannot see well enough to do their 
 work properly. 
 
CHAPTER XX 
 
 WATER SUPPLY 
 
 Materials. The water supply of the school and 
 home; a faucet, drinking fountain; water pipes, reser- 
 voir, standpipe; wells, pumps. 
 
 Water supply of the school. How are you sup- 
 plied with drinking water in your school building? 
 If from a pail or jar, what precaution is taken to 
 keep it free from dust? Are individual drinking 
 cups used? How do you get the water from the pail 
 into your cup? 
 
 If you have a drinking fountain, study it. How 
 many distinct parts do you find? How many pipes 
 are connected with it? What is the use of each? Of 
 the basin? When you turn the faucet what happens? 
 Why does the water flow out? Where does it come 
 from? How do you stop the flow? To answer this, 
 examine an unattached faucet. Look through it 
 while you turn the handle back and forth. 
 
 Study faucets at home. Can you turn the faucet 
 and leave it so the water will continue to run until 
 you turn it back, or does the water stop running 
 the moment you stop pressing on the handle or 
 
 339 
 
340 STUDIES IN SCIENCE 
 
 spigot? Where does the water come from that stands 
 in the pipe ready to flow the moment you turn the 
 faucet? Does the water flow slowly or rapidly? If 
 there are fountains or lavatories on different floors 
 of the building, test them to. determine whether there 
 is any difference in the force with which the water 
 flows. 
 
 Trace the water-pipe to the basement of the build- 
 ing. Find where it enters. How deep in the ground 
 is it? What is the size of the pipe? When a plumber 
 speaks of an inch and a quarter pipe, does he mean 
 the diameter or the circumference? 
 
 Where does the pipe come from into the basement? 
 If you could trace it underground, with what would 
 you find it connected? 
 
 Explanation. No matter what kind of drinking 
 fountain you examine, you will find it has an opening 
 for the water, a water-pipe, a basin to catch the 
 water, and a drain pipe from this. Some fountains 
 are so enclosed that you cannot see the pipes. 
 
 The faucet has a valve in it which closes the open- 
 ing completely when you turn it in one direction and 
 opens it when you turn it in the opposite direction. 
 Some faucets have a spring arranged so that when 
 you cease to press, the valve closes and stops the 
 flow of water. This is called a spring faucet. 
 
 You know from the way the water pours out when 
 
CHAPTER XX 
 
 WATEK SUPPLY 
 
 Materials. The water supply of the school and 
 home; a faucet, drinking fountain; water pipes, reser- 
 voir, standpipe; wells, pumps. 
 
 Water supply of the school. How are you sup- 
 plied with drinking water in your school building? 
 If from a pail or jar, what precaution is taken to 
 keep it free from dust? Are individual drinking 
 cups used! How do you get the water from the pail 
 into your cup? 
 
 If you have a drinking fountain, study it. How 
 many distinct parts do you find? How many pipes 
 are connected with it? What is the use of each? Of 
 the basin? When you turn the faucet what happens? 
 Why does the water flow out? Where does it come 
 from? How do you stop the flow? To answer this, 
 examine an unattached faucet. Look through it 
 while you turn the handle back and forth. 
 
 Study faucets at home. Can you turn the faucet 
 and leave it so the water will continue to run until 
 you turn it back, or does the water stop running 
 the moment you stop pressing on the handle or 
 
 339 
 
340 STUDIES IN SCIENCE 
 
 spigot? Where does the water come from that stands 
 in the pipe ready to flow the moment you turn the 
 faucet? Does the water flow slowly or rapidly! If 
 there are fountains or lavatories on different floors 
 of the building, test them to determine whether there 
 is any difference in the force with which the water 
 flows. 
 
 Trace the water-pipe to the basement of the build- 
 ing. Find where it enters. How deep in the ground 
 is it? What is the size of the pipe? When a plumber 
 speaks of an inch and a quarter pipe, does he mean 
 the diameter or the circumference? 
 
 Where does the pipe come from into the basement? 
 If you could trace it underground, with what would 
 you find it connected? 
 
 Explanation. No matter what kind of drinking 
 fountain you examine, you will find it has an opening 
 for the water, a water-pipe, a basin to catch the 
 water, and a drain pipe from this. Some fountains 
 are so enclosed that you cannot see the pipes. 
 
 The faucet has a valve in it which closes the open- 
 ing completely when you turn it in one direction and 
 opens it when you turn it in the opposite direction. 
 Some faucets have a spring arranged so that when 
 you cease to press, the valve closes and stops the 
 flow of water. This is called a spring faucet. 
 
 You know from the way the water pours out when 
 
WATER SUPPLY 341 
 
 you turn the faucet that it must be standing in the 
 pipe ready to flow the moment it has a chance. In 
 the basement you found the water-pipe coming in 
 from the ground. If you could trace this outward, 
 you would find it extending to the street where it 
 is connected with a, large pipe. The large pipes 
 are called water mains. The size depends upon the 
 amount of water needed by the people living along 
 the street. In large cities they are much larger than 
 in small towns. They vary from eight inches to two 
 or three feet in diameter. 
 
 If you follow the main you finally come to a stand- 
 pipe or a reservoir and a pumping station, usually 
 near the source of the water supply. 
 
 Visit the pumping station and have the man in 
 charge show you the pumps and explain their use. 
 You may find one pumping water into the reservoir, 
 another pumping it into mains or a stand-pipe. 
 Visit the reservoir if possible. Get its dimension 
 and determine how much water it will hold. Study 
 also the stand-pipe. How high is it? What is its 
 function? Can you make a piece of apparatus that 
 will show the principle of the stand-pipe? 
 
 The force with which the water pours out of a 
 faucet may be due to the pump at the pumping 
 station or to the stand-pipe. Often the water is 
 pumped directly into the mains. The pressure of the 
 
342 STUDIES IN SCIENCE 
 
 persistent flow coming from the pump forces the 
 water along through the mains and up into the pipes. 
 The force from the stand-pipe is due to the pressure 
 of the water itself. The stand-pipe is connected with 
 the mains, and when it is full the pressure is suffi- 
 cient to force the water into the pipes. Some force 
 is lost by friction as the water flows along, so the 
 highest faucet in the water system can not be quite 
 as high as the water in the stand-pipe. 
 
 Where does the water come from that is pumped 
 into the reservoir or stand-pipe! If the water is 
 obtained from a river, find out how far away the 
 river is and how the water gets from the river into 
 the reservoir. If the source is a lake make the same 
 investigation. How far out from the shore is the 
 water procured? 
 
 Wells. If you live where wells supply the water, 
 find out how many kinds of wells there are in your 
 district. Study the well on the school grounds. Is it 
 a drilled or dug well? How many people in the com- 
 munity use water from dug wells? What is the 
 average depth of these wells? The diameter? With 
 what are they walled up? Does the water level in 
 them vary from time to time? Locate wells that go 
 dry in the summer? Explain why. 
 
 How many drilled wells are there in the com- 
 munity? Find out how deep some of these are. 
 
WATER SUPPLY 341 
 
 you turn the faucet that it must be standing in the 
 pipe ready to flow the moment it has a chance. In 
 the basement you found the water-pipe coming in 
 from the ground. If you could trace this outward, 
 you would find it extending to the street where it 
 is connected with a large pipe. The large pipes 
 are called water mains. The size depends upon the 
 amount of water needed by the people living along 
 the street. In large cities they are much larger than 
 in small towns. They vary from eight inches to two 
 or three feet in diameter. 
 
 If you follow the main you finally come to a stand- 
 pipe or a reservoir and a pumping station, usually 
 near the source of the water supply. 
 
 Visit the pumping station and have the man in 
 charge show you the pumps and explain their use. 
 You may find one pumping water into the reservoir, 
 another pumping it into mains or a stand-pipe. 
 Visit the reservoir if possible. Get its dimension 
 and determine how much water it will hold. Study 
 also the stand-pipe. How high is it? What is its 
 function! Can you make a piece of apparatus that 
 will show the principle of the stand-pipe? 
 
 The force with which the water pours out of a 
 faucet may be due to the pump at the pumping 
 station or to the stand-pipe. Often the water is 
 pumped directly into the mains. The pressure of the 
 
342 STUDIES IN SCIENCE 
 
 persistent flow coming from the pump forces the 
 water along through the mains. and up into the pipes. 
 The force from the stand-pipe is due to the pressure 
 of the water itself. The stand-pipe is connected with 
 the mains, and when it is full the pressure is suffi- 
 cient to force the water into the pipes. Some force 
 is lost by friction as the water flows along, so the 
 highest faucet in the water system can not be quite 
 as high as the water in the stand-pipe. 
 
 Where does the water come from that is pumped 
 into the reservoir or stand-pipe! If the water is 
 obtained from a river, find out how far away the 
 river is and how the water gets from the river into 
 the reservoir. If the source is a lake make the same 
 investigation. How far out from the shore is the 
 water procured! 
 
 Wells. If you live where wells supply the water, 
 find out how many kinds of wells there are in your 
 district. Study the well on the school grounds. Is it 
 a drilled or dug well! How many people in the com- 
 munity use water from dug wells! What is the 
 average depth of these wells! The diameter! With 
 what are they walled up! Does the water level in 
 them vary from time to time! Locate wells that go 
 dry in the summer! Explain why, 
 
 How many drilled wells are there in the com- 
 munity! Find out how deep some of these are. 
 
WATER SUPPLY 343 
 
 What is their diameter? Are there any artesian or 
 flowing wells? 
 
 Experiment. What is the source of water in shal- 
 low or dug wells! 
 
 Into a shallow pan put a layer of soil or sand. 
 About half way from the center make a hole similar 
 to a dug well and wall it up with pebbles or bits of 
 rock. Continue filling in soil and walling up the well 
 till the pan is well filled. The soil should slope 
 toward the part of the pan in which the well is 
 located. Now pour water over the surface. When 
 the water disappears put on some more. Continue 
 till the soil seems well saturated. Watch the well 
 and describe what takes place. Determine whether 
 or not water comes into the well from all sides. To 
 what extent does the slope affect the amount of 
 water that flows into the well? 
 
 If this were a real well and the soil in the pan 
 were a plot of ground where you were to build a 
 home with a barn and all other buildings, where 
 would you place the house? The other buildings? 
 Where the well? Why? 
 
 Explanation. Your experiment shows the simple 
 principle by which shallow, dug wells are supplied 
 with water. The rain that falls upon the ground 
 percolates or moves slowly downward. If there is 
 a slope the water accumulates in the lowest places. 
 
344 STUDIES IN SCIENCE 
 
 "When a well is dug the water in the ground flows 
 into the hole from all sides just as it did in the 
 experiment. The higher the water stands in the sur- 
 rounding soil the higher it stands in the well. The 
 line which marks the upper surface of the water is 
 called the ground water level. During dry weather 
 this level may sink below the bottom of the well 
 and then the well becomes dry. 
 
 Wells should be placed in relation to barns and 
 other buildings so that water from around these will 
 not flow into the wells. It is often safer to dig wells 
 in the higher ground where they must necessarily 
 be made deeper. 
 
 Experiment. What is the source of the water in 
 deep, drilled wells! 
 
 Procure a large pan; a wide granite dish pan will 
 serve. Put a sloping layer of cement in the bottom. 
 To make the cement, mix together Portland cement, 
 sand and water in the proportion 1/3 cement, 2/3 
 sand. On this place a sloping layer of sand, then 
 mother layer of cement. This should not cover the 
 last three or four inches of sand in the highest part. 
 Place a layer of soil over this. Insert a glass tube 
 into the lowest part of the sand layer. Do this before 
 you put on the top layer of cement. This represents 
 a drilled well. Firm the cement closely around the 
 tube and also around the sides of the pan. Pour 
 
WATER SUPPLY 343 
 
 What is their diameter? Are there any artesian or 
 flowing wells? 
 
 Experiment. What is the source of water in shal- 
 low or dug wells! 
 
 Into a shallow pan put a layer of soil or sand. 
 About half way from the center make a hole similar 
 to a dug well and wall it up with pebbles or bits of 
 rock. Continue filling in soil and walling up the well 
 till the pan is well filled. The soil should slope 
 toward the part of the pan in which the well is 
 located. Now pour water over the surface. When 
 the water disappears put on some more. Continue 
 till the soil seems well saturated. Watch the well 
 and describe what takes place. Determine whether 
 or not water comes into the well from all sides. To 
 what extent does the slope affect the amount of 
 water that flows into the well? 
 
 If this were a real well and the soil in the pan 
 were a plot of ground where you were to build a 
 home with a barn and all other buildings, where 
 would you place the house? The other buildings? 
 Where the well? Why? 
 
 Explanation. Your experiment shows the simple 
 principle by which shallow, dug wells are supplied 
 with water. The rain that falls upon the ground 
 percolates or moves slowly downward. If there is 
 a slope the water accumulates in the lowest places. 
 
344 STUDIES IN SCIENCE 
 
 When a well is dug the water in the ground flows 
 into the hole from all sides just as it did in the 
 experiment. The higher the water stands in the sur- 
 rounding soil the higher it stands in the well. The 
 line which marks the upper surface of the water is 
 called the ground water level. During dry weather 
 this level may sink below the bottom of the well 
 and then the well becomes dry. 
 
 Wells should be placed in relation to barns and 
 other buildings so that water from around these will 
 not flow into the wells. It is often safer to dig wells 
 in the higher ground where they must necessarily 
 be made deeper. 
 
 Experiment. What is the source of the water in 
 deep, drilled wells? 
 
 Procure a large pan; a wide granite dish pan will 
 serve. Put a sloping layer of cement in the bottom. 
 To make the cement, mix together Portland cement, 
 sand and water in the proportion 1/3 cement, 2/3 
 sand. On this place a sloping layer of sand, then 
 another layer of cement. This should not cover the 
 last three or four inches of sand in the highest part. 
 Place a layer of soil over this. Insert a glass tube 
 into the lowest part of the sand layer. Do this before 
 you put on the top layer of cement. This represents 
 a drilled well. Firm the cement closely around the 
 tube and also around the sides of the pan. Pour 
 
WATER SUPPLY 345 
 
 water on the sand. Watch the well. How high does 
 the water stand in it? Can any water from the layer 
 of top soil get into it? Why! 
 
 Springs. To what extent do springs furnish water 
 in the region where you live? Describe a spring if 
 there is one near by. Is the water cool or warm? 
 Does it flow constantly? Is the region level or hilly? 
 Are there any rivers or creeks near by? How do 
 you account for springs? 
 
 Explanation. If your experiment worked prop- 
 erly, you have a clear illustration of how water is 
 supplied in drilled wells. The different layers of 
 soil in the pan represent an area on the earth's sur- 
 face where there is a layer of sand between two 
 impervious layers of material such as solid rock or 
 fine clay. The sand layer comes to the surface many 
 miles away from the spot where the well is drilled. 
 Rain falling upon this sinks down into the sand and 
 moves slowly down the slope. Since there is an 
 impervious layer under the sand the water cannot 
 move farther down, so the sand becomes saturated 
 with water and forms a vein. When the well is 
 drilled through the upper layer into this the water in 
 the vein rises through the open bottom of the pipe 
 and stands as high as the water extends into the sand 
 layer. No water from the soil near the well can enter 
 through the iron pipe. It cannot reach the sand 
 
346 STUDIES IN SCIENCE 
 
 layer which supplies the water because of the imper- 
 vious layer on top of the sand. 
 
 Springs are due to precisely the same conditions 
 as those described above except that the water makes 
 its way to the surface and flows out. 
 
 Water and health. Which of the systems that you 
 have studied is likely to supply the purest water? 
 Why! 
 
 Water may have several different kinds of impuri- 
 ties in it: 1. It may have sediment which consists 
 of small particles of sand, clay or bits of decaying 
 matter. Most of this will settle to the bottom of a 
 vessel in which the water stands quiet for some 
 time. Biver water is likely to contain more sediment 
 than lake or well water. 
 
 2. The second kind of impurity is dissolved 
 mineral compounds of various kinds. Perhaps you 
 have drunk water from springs that contained a vast 
 amount of sulphur or other substance. This kind 
 of impurity does not as a rule make water unhealth- 
 ful. In fact, some waters are regarded very healthful 
 because of the minerals dissolved in them. Most 
 well water has considerable lime dissolved in it. 
 
 3. The third kind of impurity consists of living 
 organisms in the water. Certain kinds of green plants 
 called algae sometimes grow on the walls of reser- 
 voirs or even in the water. They are not in them- 
 
WATER SUPPLY 345 
 
 water on the sand. Watch the well. How high does 
 the water stand in it? Can any water from the layer 
 of top soil get into it? Why! 
 
 Springs. To what extent do springs furnish water 
 in the region where you live? Describe a spring if 
 there is one near by. Is the water cool or warm? 
 Does it flow constantly? Is the region level or hilly? 
 Are there any rivers or creeks near by? How do 
 you account for springs? 
 
 Explanation. If your experiment worked prop- 
 erly, you have a clear illustration of how water is 
 supplied in drilled wells. The different layers of 
 soil in the pan represent an area on the earth's sur- 
 face where there is a layer of sand between two 
 impervious layers of material such as solid rock or 
 fine clay. The sand layer comes to the surface many 
 miles away from the spot where the well is drilled. 
 Rain falling upon this sinks down into the sand and 
 moves slowly down the slope. Since there is an 
 impervious layer under the sand the water cannot 
 move farther down, so the sand becomes saturated 
 with water and forms a vein. When the well is 
 drilled through the upper layer into this the water in 
 the vein rises through the open bottom of the pipe 
 and stands as high as the water extends into the sand 
 layer. No water from the soil near the well can enter 
 through the iron pipe. It cannot reach the sand 
 
346 STUDIES IN SCIENCE 
 
 layer which supplies the water because of the imper- 
 vious layer on top of the sand. 
 
 Springs are due to precisely the same conditions 
 as those described above except that the water makes 
 its way to the surface and flows out. 
 
 Water and health. Which of the systems that you 
 have studied is likely to supply the purest water? 
 Why? 
 
 Water may have several different kinds of impuri- 
 ties in it: 1. It may have sediment which consists 
 of small particles of sand, clay or bits of decaying 
 matter. Most of this will settle to the bottom of a 
 vessel in which the water stands quiet for some 
 time. Eiver water is likely to contain more sediment 
 than lake or well water. 
 
 2. The second kind of impurity is dissolved 
 mineral compounds of various kinds. Perhaps you 
 have drunk water from springs that contained a vast 
 amount of sulphur or other substance. This kind 
 of impurity does not as a rule make water unhealth- 
 ful. In fact, some waters are regarded very healthful 
 because of the minerals dissolved in them. Most 
 well water has considerable lime dissolved in it. 
 
 3. The third kind of impurity consists of living 
 organisms in the water. Certain kinds of green plants 
 called algae sometimes grow on the walls of reser- 
 voirs or even in the water. They are not in them- 
 
WATER SUPPLY 347 
 
 selves harmful. The living organisms that are to 
 be feared are bacteria, since they may produce human 
 diseases. Chief among these is the typhoid fever 
 germ. Statistics show that the spread of typhoid 
 fever is largely through drinking water. This means 
 that the germs from some one who is ill with typhoid 
 get into the water supply. If the supply is taken 
 from a river, it sometimes happens that the water 
 is contaminated several miles above the place from 
 which water is taken. You can see how easily this 
 might happen since the water is constantly moving 
 down-stream. 
 
 The same thing may happen when the supply is 
 from a lake. The bacteria may be carried into the 
 lake by drains or streams. If the water supply is 
 taken from too near the shore, some of the bacteria 
 may be distributed over the city in the water. 
 
 Shallow dug wells have bacteria carried into -them 
 with the water that flows near barns, outhouses and 
 other places where there is waste material with germs 
 in it. Typhoid fever is sometimes called a country 
 disease, since there are in proportion more deaths due 
 to this dread disease in the country and small towns 
 than in cities. The reason, of course, is that in recent 
 years more attention has been given in cities to secur- 
 ing pure water. 
 
 How to secure pure water. The drilled well sup- 
 
348 STUDIES IN SCIENCE 
 
 plying water from a great depth is usually free from 
 all disease germs. The water percolates so far 
 through the beds of sand or gravel that any bacteria 
 which may have been in it are killed. The deep 
 well then, where it is possible to secure water in this 
 way, solves the problem of pure water in the country 
 and small town. Deep wells are used as the source 
 of city water supply in many good-sized towns of 
 the Middle West. 
 
 Spring water is usually pure for the same reason 
 that deep well water is. Occasionally, however, 
 spring water is contaminated by flowing through 
 bacteria laden soil as it nears the surface where it 
 flows out. 
 
 The dug well and pure water. The dug well should 
 be placed so that water from feed lots, barns and 
 outhouses may not readily drain into it. The last 
 five or six feet of a deep dug well may be finished 
 with a layer of cement over the brick wall. This 
 prevents the ground water near the surface from 
 entering. The cement wall should extend five or six 
 inches above the surface of the ground and should 
 have a tight cover so that no impurities may enter 
 the well from the top. A deep dug well often reaches 
 a layer of saturated sand, a vein, which supplies pure 
 water. 
 
 Lakes and rivers. Cities that use lake water 
 
WATER SUPPLY 347 
 
 selves harmful. The living organisms that are to 
 be feared are bacteria, since they may produce human 
 diseases. Chief among these is the typhoid fever 
 germ. Statistics show that the spread of typhoid 
 fever is largely through drinking water. This means 
 that the germs from some one who is ill with typhoid 
 get into the water supply. If the supply is taken 
 from a river, it sometimes happens that the water 
 is contaminated several miles above the place from 
 which water is taken. You can see how easily this 
 might happen since the water is constantly moving 
 down-stream. 
 
 The same thing may happen when the supply is 
 from a lake. The bacteria may be carried into the 
 lake by drains or streams. If the water supply is 
 taken from too near the shore, some of the bacteria 
 may be distributed over the city in the water. 
 
 Shallow dug wells have bacteria carried into them 
 with the water that flows near barns, outhouses and 
 other places where there is. waste material with germs 
 in it. Typhoid fever is sometimes called a country 
 disease, since there are in proportion more deaths due 
 to this dread disease in the country and small towns 
 than in cities. The reason, of course, is that in recent 
 years more attention has been given in cities to secur- 
 ing pure water. 
 
 How to secure pure water. The drilled well sup- 
 
348 STUDIES IN SCIENCE 
 
 plying water from a great depth is usually free from 
 all disease germs. The water percolates so far 
 through the beds of sand or gravel that any bacteria 
 which may have been in it are killed. The deep 
 well then, where it is possible to secure water in this 
 way, solves the problem of pure water in the country 
 and small town. Deep wells are used as the source 
 of city water supply in many good-sized towns of 
 the Middle West. 
 
 Spring water is usually pure for the same reason 
 that deep well water is. Occasionally, however, 
 spring water is contaminated by flowing through 
 bacteria laden soil as it nears the surface where it 
 flows out. 
 
 The dug well and pure water. The dug well should 
 be placed so that water from feed lots, barns and 
 outhouses may not readily drain into it. The last 
 five or six feet of a deep dug well may be finished 
 with a layer of cement over the brick wall. This 
 prevents the ground water near the surface from 
 entering. The cement wall should extend five or six 
 inches above the surface of the ground and should 
 have a tight cover so that no impurities may enter 
 the well from the top. A deep dug well often reaches 
 a layer of saturated sand, a vein, which supplies pure 
 water. 
 
 Lakes and rivers. Cities that use lake water 
 
WATER SUPPLY 349 
 
 usually get their supply from deep water near the 
 center of the lake. This is accomplished by making 
 tunnels in the bottom of the lake extending out sev- 
 eral miles. In some cases the water is filtered through 
 beds of sand. When contamination is feared, chem- 
 icals are used in the water to kill the bacteria. 
 
 Eiver water is filtered in most places. The bene- 
 ficial results that come from attention to purifying 
 the water supply can not longer be questioned. 
 
 Sewage, How to dispose of sewage is a problem 
 that always goes along with the question of pure 
 water. If you studied a drinking fountain or faucet, 
 you found that the water from the basin or sink 
 disappeared in a waste-pipe. If you could trace this 
 pipe, you would find it connected with a sewer which 
 opens into a large street sewer. Do you know where 
 the sewers of your town discharge their contents? 
 In many places the sewage is discharged into streams 
 or lakes. From what we have already said you can 
 see that there are many objections to this. Probablj 
 the time will come when this method, except perhaps 
 in the largest cities, will be abandoned. Many small 
 cities are installing septic tanks. The tank is a large 
 receptacle of two or three compartments which 
 receives the sewage. It is made of cement so it is 
 absolutely water tight. Bacteria act upon the. mate- 
 rial changing it to gases and liquids until most of it 
 
350 STUDIES IN SCIENCE 
 
 is disposed of. The small amount of solid matter 
 known as sludge is occasionally removed from the 
 tanks and used as a fertilizer. 
 
 The need of water. The human body is composed 
 of different organs all of which are built up of tis- 
 sues. There are then several different kinds of tissue 
 in the body. 
 
 Muscle tissue composes the flesh and makes move- 
 ments possible. 
 
 Skin tissue, also called epithelium, makes the out- 
 side covering of the body as well as the lining of the 
 mouth and other inner parts. 
 
 Connective tissue is a membrane that helps to hold 
 together the different parts of the body, as the bun- 
 dles of muscle fibers. 
 
 Nerve tissue makes up the brain and nerves. 
 Fat is a tissue found in various organs. It usually 
 stores up material for future use. 
 
 Gland tissue composes certain organs which make 
 secretions for use in the body as the saliva in the 
 mouth and the digestive fluids in the stomach. 
 
 Bone and cartilage tissue are the solid, supporting 
 parts of the body. 
 
 Now all of these tissues are made up of cells so 
 small that you would need a microscope to see them. 
 Each cell is made of a substance called protoplasm, 
 and this is composed in large part of water, so that 
 
WATE& SUPPLY 
 
 usually get their supply from deep water near the 
 center of the lake. This is accomplished by making 
 tunnels in the bottom of the lake extending out sev- 
 eral miles. In some cases the water is filtered through 
 beds of sand. When contamination is feared, chem- 
 icals are used in the water to kill the bacteria. 
 
 River water is filtered in most places. The bene- 
 ficial results that come from attention to purifying 
 the water supply can not longer be questioned. 
 
 Sewage. How to dispose of sewage is a problem 
 that always goes along with the question of pure 
 water. If you studied a drinking fountain or faucet, 
 you found that the water from the basin or sink 
 disappeared in a waste-pipe. If you could trace this 
 pipe, you would find it connected with a sewer which 
 opens into a large street sewer. Do you know where 
 the sewers of your town discharge their contents! 
 In many places the sewage is discharged into streams 
 or lakes. From what we have already said you can 
 see that there are many objections to this. Probablj 
 the time will come when this method, except perhaps 
 in the largest cities, will be abandoned. Many small 
 cities are installing septic tanks. The tank is a large 
 receptacle of two or three compartments which 
 receives the sewage. It is made of cement so it is 
 absolutely water tight. Bacteria act upon the mate- 
 .rial changing it to gases and liquids until most of it 
 
350 STUDIES IN SCIENCE 
 
 is disposed of. The small amount of solid matter 
 known as sludge is occasionally removed from the 
 tanks and used as a fertilizer. 
 
 The need of water. The human body is composed 
 of different organs all of which are built up of tis- 
 sues. There are then several different kinds of tissue 
 in the body. 
 
 Muscle tissue composes the flesh and makes move- 
 ments possible. 
 
 Skin tissue, also called epithelium, makes the out- 
 side covering of the body as well as the lining of the 
 mouth and other inner parts. 
 
 Connective tissue is a membrane that helps to hold 
 together the different parts of the body, as the bun- 
 dles of muscle fibers. 
 
 Nerve tissue makes up the brain and nerves. 
 
 Fat is a tissue found in various organs. It usually 
 stores up material for future use. 
 
 Gland tissue composes certain organs which make 
 secretions for use in the body as the saliva in the 
 mouth and the digestive fluids in the stomach. 
 
 Bone and cartilage tissue are the solid, supporting 
 parts of the body. 
 
 Now all of these tissues are made up of cells so 
 small that you would need a microscope to see them. 
 Each cell is made of a substance called protoplasm, 
 and this is composed in large part of water, so that 
 
WATER SUPPLY 351 
 
 the very material of which the body is composed is 
 dependent upon water. About three-fourths of the 
 muscles are water, nine-tenths of the blood and nearly 
 one-half of the bones and cartilage. 
 
 Besides forming a part of the cells and tissues, 
 water is needed to soften all solid foods that you eat, 
 for they must be dissolved and liquefied before they 
 can be taken into the blood. Without sufficient water 
 in the alimentary canal the food moves along with 
 difficulty and indigestion is likely to follow. 
 
 Oxidation is a process of "burning" which occurs 
 in the body when the oxygen we breathe combines 
 with the food we eat. The result of oxidation is heat 
 and energy for the body. 
 
 In the process of oxidation in the cells of the body 
 waste products are produced. These must be dis- 
 solved in the watery part of the blood and carried 
 to the organs that throw them out of the body as 
 waste matter. Hence the blood must have a constant 
 supply of water. The chief avenues by which water 
 with waste material is given out of the body are 
 through the skin by perspiration, through the lungs, 
 and by way of kidneys. The amount given off through 
 the skin by the average healthy person should be two 
 pints each day, from the lungs one pint, and through 
 the kidneys three pints. 
 
 An important function of the water taken into the 
 
I 
 
 352 STUDIES IN SCIENCE 
 
 body is to flush out the system. It takes out the waste 
 materials which otherwise develop poisons. 
 
 The facts given above suggest that if you wish to 
 keep well you must drink plenty of water. An adult 
 should drink about two quarts of water a day. A 
 habit of drinking a glass of water upon rising and 
 one just before retiring is most valuable. Many of 
 the best physicians claim that no harm comes from 
 drinking as much as you desire while eating. 
 
 If there is any question as to whether water is pure 
 it should be sterilized. This is done by bringing water 
 to the boiling point, allowing it to boil a few minutes 
 and then letting it cool When cool boil it a second 
 time, put in jars or bottles, keep in the ice box or 
 other cool place. The second boiling kills any of 
 bacteria that may have escaped the first time. 
 
 Water and care of skin. Water is needed to keep 
 the skin in healthy condition. The small openings 
 from the sweat glands must be kept open in order 
 that there may be a free flow of perspiration all the 
 time. These may become clogged with bits of solid 
 matter that are left after the sweat evaporates. Then 
 the oil glands connected with the roots of the hairs 
 pour out on the skin a small amount of oil. This holds 
 bits of dust and may clog the sweat glands. Bathing 
 is necessary to keep the pores open and active. How 
 often one needs to bathe depends upon the individual, 
 
WATER SUPPLY 
 
 the very material of which the body is composed is 
 dependent upon water. About three-fourths of the 
 muscles are water, nine-tenths of the blood and nearly 
 one-half of the bones and cartilage. 
 
 Besides forming a part of the cells and tissues, 
 water is needed to soften all solid foods that you eat, 
 for they must be dissolved and liquefied before they 
 can be taken into the blood. Without sufficient water 
 in the alimentary canal the food moves along with 
 difficulty and indigestion is likely to follow. 
 
 Oxidation is a process of " burning " which occurs 
 in the body when the oxygen we breathe combines 
 with the food we eat. The result of oxidation is heat 
 and energy for the body. 
 
 In the process of oxidation in the cells of the body 
 waste products are produced. These must be dis- 
 solved in the watery part of the blood and carried 
 to the organs that throw them out of the body as 
 waste matter. Hence the blood must have a constant 
 supply of water. The chief avenues by which water 
 with waste material is given out of the body are 
 through the skin by perspiration, through the lungs, 
 and by way of kidneys. The amount given off through 
 the skin by the average healthy person should be two 
 pints each day, from the lungs one pint, and through 
 the kidneys three pints. 
 
 An important function of the water taken into the 
 
352 STUDIES IN SCIENCE 
 
 body is to flush out the system. It takes out the waste 
 materials which otherwise develop poisons. 
 
 The facts given above suggest that if you wish to 
 keep well you must drink plenty of water. An adult 
 should drink about two quarts of water a day. A 
 habit of drinking a glass of water upon rising and 
 one just before retiring is most valuable. Many of 
 the best physicians claim that no harm comes from 
 drinking as much as you desire while eating. 
 
 If there is any question as to whether water is pure 
 it should be sterilized. This is done by bringing water 
 to the boiling point, allowing it to boil a few minutes 
 and then letting it cool When cool boil it a second 
 time, put in jars or. bottles, keep in the ice box or 
 other cool place. The second boiling kills any of 
 bacteria that may have escaped the first time. 
 
 Water and care of skin. Water is needed to keep 
 the skin in healthy condition. The small openings 
 from the sweat glands must be kept open in order 
 that there may be a free flow of perspiration all the 
 time. These may become clogged with bits of solid 
 matter that are left after the sweat evaporates. Then 
 the oil glands connected with the roots of the hairs 
 pour out on the skin a small amount of oil. This holds 
 bits of dust and may clog the sweat glands. Bathing 
 is necessary to keep the pores open and active. How 
 often one needs to bathe depends upon the individual, 
 
WATER SUPPLY 353 
 
 but everyone should bathe often enough to keep the 
 skin perfectly clean. 
 
 Cleanliness is not the only reason for bathing fre- 
 quently. A bath stimulates the skin and in a way the 
 whole body. Some people find that a cold bath in 
 the morning invigorates them for the entire day. Deli- 
 cate persons sometimes find that the cold bath is too 
 stimulating to the heart. A cold bath should leave 
 one with a warm glow all over the body. This is 
 brought about in part by vigorous rubbing after leav- 
 ing the bath. Just after rising is the best time for a 
 cold bath, or when one is sweating and the body is 
 very warm, though one should use care not to stay 
 in the cold bath too long; one, two or three minutes 
 is usually sufficient. 
 
 A hot bath with soap is necessary to thoroughly 
 cleanse the skin. Hot baths should not be taken in 
 cold weather if one goes out-of-doors soon afterward. 
 The application of heat to the skin causes the pores 
 to open and the blood to flow to the surface. While 
 in this condition the body can offer little resistance to 
 the cold, so you can see why it is a dangerous thing 
 to go out-of-doors after taking a hot bath before the 
 skin has had time to recover its normal condition. 
 Just before going to bed is the best time for a hot bath. 
 
CHAPTER XXI 
 
 FORMS OF WATER 
 
 Material. Several tin cups, a small glass bottle; a 
 flask with a side delivery tube, or a rubber stopper 
 with a tube inserted in it; a measuring cup or grad- 
 uate; shallow pans, and a thermometer. 
 
 In the last chapter you found out a number of facts 
 about water as a liquid. But water exists in other 
 forms that are quite as interesting. 
 
 Experiment. Some facts about ice. 
 
 (a) Fill a small glass bottle with water and put 
 in a stopper. Set this in a dish and put it out-of-doors 
 over night when the weather is very cold. 
 
 (b) Fill a tin cup level full of water, set in a dish 
 and place out-of-doors under similar conditions. 
 
 Examine both bottle and cup the next morning. 
 What do you find 1 How do you account for the broken 
 bottle ? What evidence have you that the bottle broke 
 before all the water was frozen? What has happened 
 to the tin cup? Is it level full of ice! Which occupies 
 more space, water or ice? 
 
 Explanation. Ice, of course, is water in a solid form. 
 There is a definite point of temperature at which 
 
 354 
 
FORMS OF WATER 355 
 
 water begins to solidify. When it cools down to with- 
 in a few degrees of freezing it begins to expand, so 
 it must occupy more space. The point at which cool- 
 ing water begins to expand is 39 F. or 4 C. That 
 is why the ice bulges up in the tin cup. The force 
 of the expanding water broke the bottle. The fact 
 that you found some water frozen in the dish tells you 
 that all the water had not soJidified when the bottle 
 broke. Sometimes the force of the expanding water 
 pushes the stopper out of the bottle instead of break- 
 ing the glass. 
 
 Since water expands as it freezes, which do you 
 think is heavier, ice or water? 
 
 Experiment. Comparative weight of ice and water. 
 Put a chunk of ice at least two inches thick into a 
 deep pan of water. Does it sink or float! How much 
 of it sinks down into the water! If it were heavier 
 than water, what would it do! What would it do if 
 it were just the same weight as water! If ice were 
 heavier than water, what would happen when it forms 
 on lakes and streams! 
 
 Make a list of all the uses of ice. How is ice kept 
 for use during hot weather! If possible, visit an ice 
 house and see for yourself how it is stored and kept. 
 
 Explanation. You can readily see that to keep ice 
 during the summer months the temperature of the 
 ice house must not go higher than the melting point 
 
356 STUDIES IN SCIENCE 
 
 of ice. To keep it at this low temperature the house 
 is constructed in a way to keep out the heat. That is, 
 non-conductors are used to prevent heat from enter- 
 ing the house. 
 
 Experiments. Water vapor, (a) Put some water 
 into a tin cup or pan and measure the exact depth with 
 your ruler. Set the pan in a warm place on the rad- 
 iator, near the register, or on the stove. After a few 
 hours measure the water. Leave it in the warm place 
 for twenty-four hours and then examine it again. 
 What has become of the water? 
 
 (b) Take a flask having a long delivery tube and 
 pour in water until it is about half-full. Put in a 
 stopper. Heat the water, watching it carefully and 
 noting everything that happens. When the water is 
 boiling briskly what is taking place at the delivery 
 tube ? Look closely at the mouth of the tube and com- 
 pare what you find there with what is seen a little 
 farther out. Look in the space above the water in the 
 flask. Can you see anything! What must be in this 
 space? What is your conclusion as to whether water 
 vapor is visible or invisible? 
 
 (c) Hold a dry, cold tin cup for several minutes 
 at the mouth of the tube so that the vapor will enter 
 the cup. What happens? 
 
 Explanation. The water which was in the tin cup 
 disappeared because the heat changed it from a liquid 
 
FORMS OF WATER 357 
 
 into a vapor. The vapor went off into the air and you 
 did not see it. When any liquid changes into a vapor 
 we say that it evaporates. 
 
 The same thing took place in the flask, but because 
 more heat was applied to it the evaporation took place 
 more rapidly. Some of it changed into vapor near 
 the bottom of the flask and formed large bubbles which 
 came to the surface of the water and broke. This 
 process we call boiling. 
 
 The space above the boiling water and at the mouth 
 of the delivery tube seemed empty because water vapor 
 is invisible. What then is the steam that you saw a 
 little farther out from the tube? Your second experi- 
 ment probably helped you to solve that problem. When 
 you allowed the vapor to enter the tin cup it was 
 changed back into water. The steam that you saw 
 was vapor changing into water. At first the water 
 drops are so tiny that they float in the air making 
 the cloud of steam. When water boils and changes 
 rapidly into vapor we sometimes call the process vap- 
 orization instead of evaporation. The process by 
 which vapor is changed back into water is called 
 condensation. 
 
 Experiments. What conditions influence the evap- 
 oration of liquids? 
 
 (a) Measure or weigh an exact amount of water 
 and put it into a shallow pan. Put the same amount 
 
358 STUDIES IN SCIENCE 
 
 into a pint cup and into a pickle bottle. Set the three 
 side by side. The next day measure or weigh the 
 amount left in each. From which has the greatest 
 amount of water evaporated! The least! How do 
 you account for the difference! 
 
 (b) Put equal amounts of water into two tin cups 
 or tumblers of exactly the same shape and size. Put 
 one in a warm, the other in a cool place. After twenty- 
 four hours measure the water in each and account for 
 the difference. 
 
 (c) Place equal amounts of water in two tin cups. 
 Set them side by side where there is a draft of air. 
 If it is not freezing weather set them out-of-doors. 
 Cover one cup closely with a saucer or another cup.. 
 Leave the other open. Measure the water the. next 
 day and explain the difference. 
 
 Explanation. Your experiments show the following 
 truths : 
 
 1. Water evaporates more rapidly from a large 
 exposed surface than from a small one. 
 
 2. The higher the temperature the more rapid the 
 evaporation. 
 
 3. Evaporation is more rapid when air moves over 
 the surface of the water. 
 
 You may call these the laws of evaporation. They 
 are just as true of other liquids as of water. All 
 liquids, however, do not evaporate at the same rate. 
 
FORMS~OF~ WATER] 359 
 
 You can prove this by putting the same amount each 
 of water, milk and alcohol into cups and allowing 
 them to stand for a number of hours, then noting 
 what is left of each. 
 
 Make a list of all the applications and illustrations 
 of the laws of evaporation that you can think of. 
 
 Experiment. What is the effect of evaporation upon 
 surrounding bodies? 
 
 (a) Dip your finger into water and then rub it on 
 the back of your hand. Hold your hand up in the 
 air waving it gently. How does the wet spot feel? 
 Touch your hand in the same way with alcohol. What 
 happened to the water and alcohol! 
 
 (b) Dip the bulb of a thermometer into water or 
 alcohol. Wave it gently back and forth till the liquid 
 has all evaporated. Does the mercury rise or fall! 
 What is your answer to the question at the beginning 
 of this experiment! Why do you feel chilly when 
 you sit in damp clothing! Why does sprinkling the 
 street on a hot summer day cool the air! 
 
 Explanation. When a liquid is changed into a 
 vapor heat is used in producing the change. The water 
 and alcohol used or absorbed some of the heat from 
 your hand in evaporating or changing to a vapor and 
 your hand felt cool. The heat of your body is used 
 to evaporate the water from damp clothing. In the 
 same way the thermometer was cooled by the evapora- 
 
360 STUDIES IN SCIENCE 
 
 tion of the liquid and the mercury went down. To 
 state it briefly, you may say: Evaporation has a cool- 
 ing effect upon surrounding bodies. 
 
 Artificial ice. The manufacture of artificial ice is 
 dependent upon the law you have just discovered. 
 The ice plant has a number of parts, but the part in 
 which the ice is made is a huge tank filled with brine 
 through which a coil of pipes extends. Sitting in the 
 brine are rectangular cans filled with pure water and 
 
 Fig. 66. Interior of tank room in an ice factory. The brine tank 
 and the ammonia coils are under the floor. 
 
 tightly closed. At just the right moment a valve is 
 opened allowing liquid ammonia to enter the pipes. 
 The ammonia at once changes to vapor or gas so 
 rapidly that it absorbs a vast amount of heat from 
 the brine. The brine in turn absorbs heat from the 
 water in the cans. This process continues until the 
 water is frozen. 
 
FORMS OF WATER 361 
 
 The regulation of heat in the human body. The last 
 experiment will help yon to understand how the heat 
 of your own body is kept regular. You probably know 
 that a person who is in good health has a normal tem- 
 perature of about 98 F. The heat of the body is pro- 
 duced by oxidation in the cells. The heat is regulated 
 in two ways. 
 
 1. By the perspiration, which is poured out upon 
 the surface of the skin. The heat of the body evap- 
 orates this moisture and thus the body is cooled. The 
 warmer the temperature the more rapid is the flow 
 of perspiration and the more heat is used in its evap- 
 oration, hence the body temperature is kept from 
 rising when one perspires. Some moisture is con- 
 stantly being given off through the skin even though 
 it is not noticeable. 
 
 2. The body heat is also regulated by the loss of 
 heat due to the fact that the air surrounding the 
 body is usually cooler than the body. The skin 
 radiates heat and the blood near the surface becomes 
 cool and flows toward the interior of the body, while 
 warmer blood takes its place. The more rapidly the 
 warm blood flows through the skin the more heat 
 will be lost in a given time. 
 
 Heat of vaporization. The heat that is used in 
 vaporizing liquids is called the heat of vaporization. 
 This heat, does not affect temperature. 
 
362 STUDIES IN SCIENCE 
 
 Experiment. Fill a tin cup or glass flask half full 
 of cold water. Set it over an alcohol lamp. Hold a 
 thermometer in the water, do not let it touch the 
 bottom, and watch the mercury. How high does it 
 rise? What temperature is indicated when the water 
 boils! Keep the thermometer in the boiling water 
 several minutes or until you are sure that the mer- 
 cury is not changing its position. Why does not the 
 heat that is passing into the water continue to make 
 it hotter? 
 
 The heat at first was used in changing the tem- 
 perature. When the water began to boil all the heat 
 was used in changing the water into vapor. An 
 interesting fact about this heat of vaporization is 
 that when the vapor changes back to water or con- 
 denses it gives out as much heat as was used in 
 changing it into vapor. This explains how steam 
 from a boiler heats a radiator. The vapor or steam 
 enters the radiator, cools and changes back to water. 
 In this process it gives out all the heat that was 
 used in vaporizing it, and thus heats the radiator. 
 
 Water vapor in air. Is there any water vapor in 
 the air of your school room or home? How do you 
 know? Think of the frost that gathers on the win- 
 dows on a cold night or the moisture that gathers 
 on the outside of a pitcher on a warm summer day. 
 
 Is there water vapor in the air out-of-doors? Where 
 
FORMS OP WATER 363 
 
 does it come from? How are clouds formed? What 
 causes rain? Snow? 
 
 Evaporation is constantly taking place from all 
 bodies and streams of water as well as from the soil. 
 When air is warm it can hold a great deal of vapor. 
 When a mass of air is cooled the vapor begins to 
 condense and form clouds, just as it did from the 
 tube of the flask. If it is cooled still more, the tiny 
 drops unite and form larger ones. Presently they 
 become so large that they can no longer float in the 
 air. They fall and we have a shower of rain. 
 
 Sometimes the vapor becomes so cold that it freezes 
 or forms crystals before it is condensed into water. 
 Then it falls in the form of snow. When there is a 
 light, fine snow catch some of the crystals on a piece 
 of dark cloth or your coat sleeve and study their 
 shape. How many different forms do you find? 
 Snow flakes are composed of great masses of the 
 six-pointed star crystals. 
 
CHAPTER XXII 
 
 HEAT AND HEATING 
 
 Material. The heating plants of the school and 
 home; candles; alcohol lamp or Bunsen burner; other 
 simple pieces of apparatus suggested in connection 
 with experiments. 
 
 Heating of the school building. How is your school 
 room heated 1 ? Look around until you find the source 
 of the heat. You may find a stove, a hot air register, 
 or a steam radiator. 
 
 Experiment. Study of air currents in connection 
 with the source of heat. Make a very fine fringe of 
 tissue paper about eight or nine inches long and an 
 inch or two wide. Fasten this to a long stick by 
 means of a rubber band or paste. A lighted candle 
 or piece of smoking punk will give more definite 
 results. Hold the fringed paper or candle close to 
 the register. What happens! Try it in various posi- 
 tions. Hold it close to the ceiling in the vicinity of 
 the register. Try it in various parts of the room. 
 What causes it to move? What direction are the air 
 currents moving with reference to the register! 
 
 If there is another register in the room, make the 
 same tests. Is the air coming in or going out of this 
 
 364 
 
HEAT AND HEATING 365 
 
 one ? Decide which is the hot and which is the cold 
 air register. If you have a stove or steam radiator 
 in the room, try the same experiments with them. 
 Hold the fringed paper or candle above them, at the 
 sides, near the top, near the floor. Hold it in the 
 vicinity of windows and doors. Open a door about 
 twelve inches; hold the candle first near the top of 
 the opening. Slowly move it downward. How do 
 you account for what takes place? Try the same 
 experiment at home; first with a door opening into 
 another room; second with one opening out-of-doors. 
 
 Explanation. Your experiments have shown you 
 that there are movements of air in the room. The 
 warm air is moving in one direction, the cooler air 
 is moving in the opposite direction. The warm air 
 moves toward the upper part of the room, spreads 
 out in all directions, and then as it cools slowly 
 moves downward. 
 
 Experiments. Do you find movements of air around 
 any heated body? 
 
 Light a piece of a candle about four or five inches 
 tall. Cut a strip of blotting paper about half an 
 inch wide, or use punk. Light it, then blow out the 
 flame and hold it so that the smoke may move with 
 the air currents around the burning candle. Does 
 the smoke move toward or away from the flame? 
 What is the movement a^Qye the flame? Where is 
 
366 
 
 STUDIES IN SCIENCE 
 
 the air about the candle the hottest! Does the cool 
 air move toward or away from the heat of the candle ? 
 Explanation. Currents of air due to unequal heat- 
 ing are called convection currents. Why does the 
 air move! Before you try to solve this problem, 
 make a study of the source of heat. If you trace 
 to its source the hot air that comes into the room 
 through the register, you will find it starts from a 
 furnace or a heated room in the basement, and is 
 
 carried upward 
 through a pipe 
 in the wall that 
 finally opens 
 into the regis- 
 ter. 
 
 The hot air 
 furnace. Make 
 a careful study 
 of the furnace. 
 Write the names 
 of all the parts 
 and try to de- 
 termine their 
 uses. If you 
 have a furnace 
 at home, study it and report what you find. 
 
 How large is the fire pot! What is the distance 
 
 Fig. 67. Convection currents from a hot 
 air furnace. (After Barber.) 
 
HEAT AND HEATING 367 
 
 from the outside of the jacket to the inside of the 
 furnace! What provision is made for air to enter 
 the jacket! How many cold air ducts are there? 
 Where do they enter the jacket? How many hot 
 air ducts are there? To what part of the jacket 
 are they attached? Investigate carefully to see 
 whether there is any chance for air from the base- 
 ment to get into the jacket. Find the air duct that 
 leaves the furnace and goes to your room. If you 
 are studying your home furnace, find the ducts 
 leading to the various rooms. Trace the cool air 
 ducts to the source of fresh air. Where do you find 
 them? Do they get their supply of cool air from 
 the outside or the inside of the building! Where 
 are the cold air registers in your home? Trace the 
 convection current from the jacket to your room 
 and back to the furnace. What provision is made in 
 your home to purify the air before it returns to 
 the furnace? 
 
 In a large school building you may find that the 
 heated air comes from a room in the basement 
 instead of from a jacket. In this kind of a heating 
 plant you will find openings from out-of-doors into 
 the basement. The pure cold air passes over a num- 
 ber of hot steam pipes; then by means of fans it is 
 forced into a large room. From this room the hot 
 air ducts carry it to the various rooms of the build- 
 
368 STUDIES IN SCIENCE 
 
 ing. With such a system you will find that the cool, 
 impure air passes out of the building through ducts 
 arranged for this purpose. You can see these open- 
 ings like small chimneys on the top of the building. 
 
 In homes heated by hot air furnaces, the cold air 
 registers are frequently placed in the front hall, 
 sometimes in the dining or the living rooms near a 
 window. How is fresh air supplied when this is 
 the easel 
 
 Jacketed stove. If your school room is heated by 
 a jacketed stove, study its parts as suggested for 
 the furnace. Find the duct for the entrance of cool 
 air to the jacket, the one for warm air to leave the 
 jacket. 
 
 How wide is the air space between the jacket and 
 fire bowl? What provision do you find for the escape 
 of impure air? Test with a thermometer different 
 parts of the room and decide whether or not a jack- 
 eted stove heats the entire room evenly. 
 
 If you have an ordinary heating stove, trace the 
 convection currents from this to all parts of the 
 room. Also test the temperature in different parts. 
 
 Experiments. What causes convection currents of 
 air? 
 
 1. Stand a thermometer on the floor of the room 
 for several minutes and take the reading. Now place 
 it high up in the room, let it remain a while and take 
 
HEAT AND HEATING 369 
 
 the reading. Which position shows the highest tem- 
 perature ? 
 
 2. Into a small portion of hot water put a few 
 drops of red ink. Fill a tumbler half full of very 
 cold water. With a common dropper or fountain 
 pen filler put some of the hot red water into the 
 bottom of the glass of cold water. What does it do? 
 
 3. Hold a small piece of wood or cork in the 
 bottom of a glass of water. Remove your fingers. 
 What happens? 
 
 Why did the piece of wood come to the top of 
 the water? Why did the warm water come to the 
 top and float on the cold water? Why is the warmest 
 air at the top of the room? The next experiment 
 will help to answer these questions. 
 
 4. Tie a piece of sheet rubber very securely over 
 the top of a flask. Now heat the flask. Why does 
 the rubber bulge upward? What is in the flask? 
 You can show the same principle by another experi- 
 ment. Hold the mouth of an open flask under water. 
 With an alcohol or gas lamp heat the flask. Why 
 do bubbles of air come out into the water? 
 
 Explanation. You no doubt see that the wood 
 floats on the water, the warm water floats on the 
 cold, and the warm air floats on the cool air because 
 in each case the body that floats is lighter than the 
 other one. Your experiments with the flask full of 
 
370 STUDIES IN SCIENCE 
 
 air tell you that when air is heated it expands and 
 occupies a larger space. In the first case it pushed 
 the sheet rubber upward; in the second it came out 
 of the flask into the water. If it expands or spreads 
 out, any definite portion of it must, of course, become 
 lighter. 
 
 When the air in the jacket of the furnace or stove 
 is heated it expands, becomes lighter and the cold 
 air below floats or pushes it upward, through the 
 pipes or ducts and into the room. In the room the 
 same thing occurs. The warm air is pushed upward; 
 it cools and slowly drops down. There are then 
 constant currents all over the room. This continues 
 as long as some air is warm and light and some cool 
 and heavy. The heavy air always moves toward the 
 light air, floating or buoying it upward. The greater 
 the difference in temperature the more rapid is the 
 movement. 
 
 Convection currents in a chimney. What is the 
 purpose of the draft at the lower front part of a 
 stove or furnace? What causes the cold air to enter! 
 Trace the convection current from the room through 
 the stove and out at the chimney. Why does the 
 opening of the check draft at the back of the furnace 
 keep the fire from burning so rapidly? Why does 
 closing the damper in the pipe have the same effect? 
 
 Explanation. When the fire begins to burn and 
 
HEAT AND HEATING 371 
 
 heat the air in the stove, the cold air below pushes 
 in and the heated air with the smoke and gases from 
 the burning fuel are pushed up the chimney. There 
 must be a fresh supply of air in the stove or there 
 can be no fire, so this movement of convection cur- 
 rents up the chimney helps to keep the fire burning. 
 When you close the draft below you shut out a part 
 of the air supply, so the fire cannot burn so rapidly. 
 At the same time you lessen the movement up the 
 chimney. When you open the check draft the cold 
 air rushes in and cools the air in the pipe and chim- 
 ney, thus causing the convection current to move 
 more slowly. 
 
 If the lower part of the furnace or stove becomes 
 clogged with ashes, this cuts off the supply of fresh 
 air to the fuel and retards the burning. 
 
 Convection currents and wind. Have you ever 
 stood near a bonfire and watched the strong current 
 carry light bits of materials upward? And have you 
 felt the cold air rushing around you toward the fire? 
 If you can explain the reason for this strong move- 
 ment of air toward the fire, then you understand 
 pretty well the cause of all winds on the earth's 
 surface from a light breeze to a raging tornado. If 
 any area on the earth's surface becomes heated more 
 than the surrounding areas, what will be the effect 
 upon the air? Will the air move away from or toward 
 
372 STUDIES IN SCIENCE 
 
 the heated area! The greater the difference in tem- 
 perature between the two areas, the more rapidly will 
 the wind blow. Since the difference of temperature 
 really causes differences in weight and pressure of 
 the air, we usually call the area of light air a low 
 pressure region, and the area of heavy air a high 
 pressure one. The wind always blows toward the 
 light or low pressure region. 
 
 Fuels. Make a list of all the different kinds of 
 fuel that you know. What is used in your home for 
 heating purposes, for cooking? By reference to your 
 geography locate the chief anthracite or hard-coal 
 fields; the bituminous or soft coal fields; regions 
 where wood is still used. Make a comparative study 
 of the prices of different kinds of fuel. 
 
 Experiments. How fuels burn. Look into a fur- 
 nace or stove and watch the burning of the fuel. 
 What do you see happening 1 ? 
 
 Take a small splinter from a pine board. It should 
 be eight or nine inches long and not less than half 
 an inch wide. A pointed piece split from a lath is 
 good for this experiment. Hold the end of it in a 
 candle flame till it begins to burn. Watch it burn 
 a few moments, then blow out the flame. What con- 
 tinues to come from the wood? Put a lighted match 
 in the smoke. What happens? Has the stick entirely 
 ceased burning T7hen the flame is extinguished? Blow 
 
HEAT AND HEATING 373 
 
 gently upon the glowing portion. Does it burn more 
 or less brightly? Which burns more closely to the 
 wood, the flame or the glow? What changes take 
 place in the color of the wood as it burns? What is 
 left after the black portion is burned? 
 
 Explanation. At first the wood burned with a 
 flame. When you extinguished the flame by blow- 
 ing upon it, you found that the stick still smoked, 
 and by applying a match you could start the flame 
 again. The smoke is made up of gases from the wood 
 that burn with a flame. The black portion that is 
 left after the gases are burned is charcoal. Char- 
 coal is nearly all carbon. The solid carbon burns 
 with a glow and gives out much heat. The white 
 part that is left after the charcoal burns is called 
 ash or ashes and is composed of minerals that will 
 not burn. If you apply these observations to the 
 coal or wood, in the stove or furnace, you find exactly 
 the same thing happening. The gases burn with a 
 flame, the solid carbon, charcoal in wood, coke in 
 coal, burn with a glow. 
 
 Experiments. What is needed besides fuel to pro- 
 duce burning? 
 
 1. Light a fresh splinter of wood and when it is 
 burning brightly thrust it into a tumbler. Hold 
 both tumbler and splinter sideways. Does it burn 
 as long as when you hold it out in the air? 
 
374 STUDIES IN SCIENCE 
 
 2. Light a candle that is about two inches high, 
 set it on the table and turn a tumbler over it. Why 
 does the flame go out! 
 
 These simple experiments show that you can not 
 burn any material without air. In fact, burning is 
 a chemical process. "When you held the splinter of 
 wood in the flame, it became heated and a portion 
 of it was changed into gas or smoke. When there 
 was enough of this heated gas, the oxygen of the air 
 began to unite with it. This union is called combus- 
 tion, or, in everyday terms, burning. The parts of 
 the wood and the oxygen unite and form new sub- 
 stances that go off into the air of the room. When 
 the gas is all burned out of the wood, the solid 
 carbon is left and the oxygen continues to unite with 
 it. This union is accompanied by a glow instead of 
 a flame. Oxygen will not unite with the minerals, 
 so when the burning ceases the ash is left. When- 
 ever anything is burning then, it means that oxygen 
 is uniting with it and is forming a new substance. 
 One of the substances formed is carbon dioxide, of 
 which you will learn more in the next chapter. 
 
 Like all the other elements of the air, oxygen is 
 invisible. Nevertheless, you can find out something 
 about it by an experiment. 
 
 Experiment. How to make oxygen. Mix together 
 equal portions of crushed potassium chlorate and 
 
HEAT AND HEATING 
 
 375 
 
 manganese dioxide. Put two or three spoonfuls into 
 a test tube. Place a stopper in the open end with a 
 tube passing through it. Fill a few jars or bottles 
 with water and invert them in a pan of water. Now 
 heat the substance for a few minutes, and place the 
 end of the rubber tube into one of the inverted bot- 
 tles. Note what takes place. When all the water 
 has been driven out, insert the tube into another 
 bottle. Continue this until all the bottles are filled 
 with oxygen. 
 
 Explanation. You have been generating oxygen. 
 Potassium chlorate is a compound made of three 
 
 Fig. 68. Apparatus for making oxygen. 
 
 different elements united into one substance. These 
 are oxygen, potassium, and chlorine. When you 
 applied heat the compound was decomposed or broken 
 up. The oxygen was set free and escaped through 
 
376 STUDIES IN SCIENCE 
 
 the tube. The manganese dioxide was put in to help 
 set the oxygen free at a low temperature. That is, 
 without it you would have to make the potassium 
 chlorate much hotter to release the oxygen. The 
 oxygen passed through the tube up into the bottle 
 of water. As it is lighter than water it went to the 
 top, and as it filled the bottle the water was forced 
 out. 
 
 How oxygen behaves. Light a splinter of wood, 
 allow it to burn a minute. Note the size and color 
 of the flame. Now, invert one of the bottles contain- 
 ing oxygen and insert the burning splinter into it. 
 What change takes place in the burning? Light 
 another splinter and allow it to burn a moment. 
 Then blow out the flame. Insert the glowing splinter 
 into a bottle of oxygen. What happens? Twist a 
 piece of wire around a small bit of charcoal. Set 
 the charcoal on fire, then lower it into a bottle of 
 oxygen. Do the same with a candle. 
 
 All these experiments tell you that burning or 
 combustion takes place much more rapidly in oxygen 
 than in air. What really happens is that the oxygen 
 unites with the elements of the wood producing at 
 the same time flame and heat. The chief element 
 in wood is carbon, and the chief compound formed 
 by the union of oxygen and wood is carbon dioxide. 
 
 Experiment. Conduction of heat. Put the end of 
 
HEAT AND HEATING 377 
 
 an iron rod or poker into a fire or the flame of an 
 alcohol lamp. Remove it after several minutes. How 
 far from the point where it was surrounded by the 
 fire can you detect heat? What must have taken 
 place in the iron? Think of other illustrations which 
 show that heat seems to travel slowly through a body. 
 Think of materials that do not allow heat to move 
 readily through them in this way. If you should 
 place a rod of wood in the fire instead of iron, what 
 would happen? What is the value of wooden handles 
 on cooking utensils? Why is woolen cloth or fur 
 warmer than cotton or linen? 
 
 Explanation. A substance like iron that permits 
 heat to move rapidly through it from one little par- 
 ticle to another is called a conductor of heat. Most 
 metals are good conductors. Wood is a non-con- 
 ductor. It may be hot enough to burn and yet be 
 cool a few inches from the flame. 
 
 Certain kinds of cloth are excellent non-conduc- 
 tors of heat. Since your body produces its own heat, 
 your clothing keeps you warm because it prevents 
 the heat from passing off into the air. Wool and 
 fur are better non-conductors than cotton. Linen is 
 cooler than any of the others because it is a better 
 conductor. Air is one of the best non-conductors. 
 It is really the air among the fibers of wool and fur 
 that makes them such excellent non-conductors. 
 
378 
 
 STUDIES IN SCIENCE 
 
 The fireless cooker. The fireless cooker is a prac- 
 tical application of the principle of non-conduction. 
 You may make one of these cookers with very little 
 expense. Procure a large tin coffee bucket and 
 another one three or four inches less in diameter. 
 Both should have close fitting lids. Cover the small 
 pail all over including the lid with two layers of 
 asbestos paper. Line the large pail with the same 
 material. Put a packing three or four inches deep 
 of excelsior in the bottom of the large pail and set 
 the small pail upon this. Now fill in the space 
 between the two pails with excelsior, pushing it down 
 
 firmly. Newspa- 
 pers torn to shreds 
 may be used in- 
 stead. Foods such 
 as rice, breakfast 
 foods, beans and 
 meats, may be 
 cooked by first 
 heating them to 
 the boiling point, 
 or, in the case of 
 meat and beans, 
 cooking for about 
 fifteen or twenty 
 minutes, then plac- 
 
 Cork 
 
 Fig. 69. Section of a fireless cooker, 
 s. Soapstone; k. Kettle. 
 
HEAT AND HEATING 379 
 
 ing the warm kettle or pan in the cooker. Cover 
 quickly and allow to stand from three to five hours 
 or all night. The non-conducting substances, asbestos 
 and excelsior, retain the heat and the food slowly 
 cooks. Two boxes may be used instead of tin pails. 
 
 Experiment. Radiant heat. Heat the end of an 
 iron rod or poker very hot. Now hold your hand 
 near the heated portion, first beneath, then on the 
 sides, then above, and determine whether or not you 
 can feel heat coming from it in all directions. The 
 heat that is given off in straight lines from any heated 
 body is called radiant heat. Every heated body gives 
 out radiant heat equally in all directions. An ordi- 
 nary heating stove or a steam radiator heats the room 
 in two ways : 1. It heats the air around it, which you 
 have found causes convection currents that carry 
 the heat through the room. 2. It sends out radiant 
 heat in all directions. For this reason objects in 
 the room nearest the source of heat become much 
 warmer than those farther away. You may have 
 observed that steam and hot water radiators are 
 placed in the coldest part of the room so that the 
 heated air will move rapidly to all other parts. 
 
 The heat that comes from the sun is radiant heat. 
 The earth absorbs it and becomes warm, then it in 
 turn, especially at night and in winter, cools by 
 radiating its heat into the air. 
 
380 
 
 STUDIES IN SCIENCE 
 
 Measuring temperature. What instrument do you 
 use to determine the temperature of a room or any 
 body? Examine a thermometer. Name everything 
 that you find. What is the highest number of the 
 scale? The lowest? How many degrees apart are 
 the lines of the scale? What degree is marked 
 " Freezing "1 What is the name of the thermometer? 
 You may find instead of the name the letter F or C. 
 The former stands for Fahrenheit; the latter for 
 Centigrade. The Fahrenheit scale has 180 degrees 
 between the freezing point and the boil- 
 ing point; the Centigrade scale only 100 
 degrees. 
 
 Put the bulb into a dish of melting ice 
 or snow and watch the mercury. Describe 
 what happens. If it is a Fahrenheit ther- 
 mometer and has a scale numbered as high 
 as 212 ; put the ice cold water into a tin 
 cup and hold a thermometer in it. Now 
 heat the water slowly until it boils. Do 
 not let the thermometer rest on the bottom 
 of the cup. Describe what happens. Why 
 does the mercury change its position? 
 
 Experiment. Why does the mercury 
 stop at a certain point in the melting ice, 
 and at another definite point in boiling 
 water? 
 
 Fig. 70. A 
 Centigrade 
 and a Fahr- 
 enheit Ther- 
 mometer. 
 
HEAT AND HEATING 381 
 
 Fill a flask with cold water, place in the flask a 
 stopper with a small glass tube twelve or fifteen 
 inches long passing through it. Push the stopper 
 down until the water stands a short distance up in the 
 tube. Now slowly heat the flask. What happens? 
 When the water has almost reached the top of the 
 tube, set the flask in a cold place and watch for 
 results. How did heat affect the water? How did 
 cold affect it? 
 
 Try the same experiment with some other liquids 
 as alcohol, vinegar, or skimmed milk, and compare 
 results. 
 
 Explanation. Your experiments show that water 
 and other liquids expand when heated and contract 
 when cooled. Most thermometers have the tube filled 
 with mercury; some have alcohol. These liquids 
 expand with heat and contract with the cold. Water 
 could be used to make a thermometer, but since it 
 freezes at a much higher temperature than mer- 
 cury or alcohol, you can see that it would not be of 
 much use. 
 
 You found in testing your thermometer that the 
 melting point of ice or snow is zero on the Centi- 
 grade and thirty-two on the Fahrenheit. Water 
 freezes at the same temperature that ice melts. When 
 a pan of ice is melting the temperature remains at 
 32 F. or C. until all the ice is melted. Zero on 
 
382 STUDIES IN SCIENCE 
 
 the Fahrenheit scale marks the temperature at which 
 a mixture of salt and ice freezes. 
 
 You found that water boiled at something below 
 212 F. or 100 C., and as long as you kept the ther- 
 mometer in the boiling water it did not go any 
 higher. At sea level the boiling point of water is 
 exactly 212 F. and 100 C. That shows that no 
 matter how much heat you put into water after it 
 begins to boil, it does not get any hotter. What does 
 this heat do! 
 
 The refrigerator. Examine a refrigerator. How 
 many distinct parts has it? Of what material is the 
 outside made! The inside? How wide a space is 
 there between the outside and the inside wall? What 
 is the value of this space? Where is the ice placed, 
 above or at the side of the food? How many open- 
 ings do you find between the food compartment and 
 the ice box? Hold a piece of smoking punk or paper- 
 lighter both below and above these openings and 
 determine the direction of the air currents. In what 
 direction is the cold air moving from the ice? The 
 warm air from the food? What causes the convec- 
 tion current? Test the temperature of the food com- 
 partment ; of the ice box. Compare with outside 
 temperature. In making the temperature test leave 
 the thermometer several minutes in each compart- 
 ment of the refrigerator with the doors all closed, 
 
HEAT AND HEATING 383 
 
 then read it quickly before you remove it from the 
 compartment. 
 
 Explanation. The refrigerator illustrates several 
 of the principles you have been studying. The space 
 between the inner and outer wall is filled with some 
 kind of non-conducting material that prevents some 
 heat from entering the refrigerator. The air in the 
 space is itself a poor conductor of heat. The ther- 
 mometer told you that the air leaving the ice box 
 is cooler than that in the food compartment. It moves 
 downward at the central opening just under the ice, 
 while the warmer air moves upward through the 
 side openings. This warm air passes over the ice, 
 is again cooled, and again drops down into the food 
 compartment. The heat in the warm air is used to 
 melt the ice. This is the chief reason that it cools 
 so quickly. 
 
 Your refrigerator may have an opening at each 
 side instead of one in the middle. In that case the 
 cold air goes down one side and the warmer air up 
 the other. Some refrigerators have the ice box at 
 the side instead of at the top. The openings are 
 arranged so that the cold air moves downward on 
 the side toward the ice and upward on the other side. 
 
 Making ice cream. If you have ever made ice 
 cream you know that ice and salt are placed in the 
 freezer around the can that holds the cream. The 
 
384 STUDIES IN SCIENCE 
 
 ice begins to melt and the salt dissolves and soon 
 the cream is frozen. Ice in the process of melting 
 or changing to water absorbs heat just as water 
 changing to vapor does. In the freezer the melting ice 
 uses up heat from the cream, but it probably would 
 not cool it enough to freeze if it were not for the salt, 
 which causes the ice to melt more rapidly. The 
 temperature of a mixture of salt and ice is much 
 lower than that of melting ice alone, as you have 
 already discovered from your study of the Fahren- 
 heit thermometer. The heat absorbed by the mix- 
 ture soon cools the cream down to the freezing point. 
 
CHAPTER XXIII 
 
 ATE 
 
 What air is. You can not study the heating of 
 the home without at the same time giving some atten- 
 tion to air and ventilation. You have already found 
 that heating buildings by any system depends largely 
 upon air currents. 
 
 What is air? It is not easy to answer this ques- 
 tion. In the first place, air is invisible. You cannot 
 see it but you can feel it rushing against you when 
 the wind blows, or when you run or ride rapidly. 
 It fills every space on the earth that is not occupied 
 by something else. If you pour water out of a 
 pitcher, air immediately rushes in and fills up the 
 space. When you say a cup, a box, or a bottle is 
 empty, you really mean that it has nothing in it but 
 air. Air fills the small spaces in the soil when they 
 are not full of water. Even the water in streams, 
 lakes, and the ocean has air mixed with it. If it 
 were not for this, fish and other water animals could 
 not exist. Air surrounds the entire earth like a great 
 envelope, extending outward at least 100 miles, pos- 
 
 385 
 
386 STUDIES IN SCIENCE 
 
 sibly more. We usually speak of this envelope of 
 air as the atmosphere. 
 
 Air is a mixture of several gases. You know 
 already what some of them are. You remember that 
 the part of the air that unites with wood and other 
 materials in burning is oxygen. This is the most 
 important gas in the air. All animals and plants as 
 well as fires are dependent upon it for existence. 
 About twenty per cent of pure air is oxygen. 
 
 You have also found that there is water vapor 
 in the air. It contains three other gases. Nitrogen 
 constitutes nearly seventy-eight per cent of the entire 
 bulk of air. Then there is some argon and a small 
 amount of carbon dioxide. Beside the gases air 
 always contains a great number of floating dust par- 
 ticles. 
 
 The proportion of the gases in the air varies from 
 time to time, and the amount of water vapor varies 
 greatly. There is always a much larger per cent 
 preceding rainstorms. 
 
 The air that you exhale has more carbon dioxide 
 and less oxygen than the air you inhale. Exhaled air 
 contains about 4 per cent carbon dioxide and 16 per 
 cent oxygen. 
 
 The different substances in pure air, with the ap- 
 proximate amount of each, is shown in the following 
 table : 
 
AIR 387 
 
 Per cent, 
 of volume 
 
 Nitrogen 77.42 
 
 Oxygen 20.77 
 
 Carbon dioxide 0.03 
 
 Argon and other gases 0.93 
 
 Water vapor 0.85 
 
 100.00 
 
 Facts about air. There are some other facts con- 
 cerning air that you can find out by experiment. 
 You will need a tumbler, a tall wide-mouthed bottle, 
 a tube about fifteen inches long with a stopper in 
 one end; a tube five or six feet long; another of small 
 diameter about thirty inches long. 
 
 Experiment 1. Fill the tumbler with water. Hold 
 your hand over the mouth and invert the tumbler 
 in a pan of water with the mouth just under the 
 surface. 
 
 Experiment 2. Try the same experiment with the 
 tall bottle and the long tube. What holds the water 
 up in the vessels? 
 
 Experiment 3. Fill the 15-inch tube and invert 
 as you did the tumbler and bottle. While you are 
 holding it remove the stopper from the upper end. 
 What happens? Why did the water flow out? 
 
 Explanation. The last experiment will help you 
 to answer the question raised by the other two. When 
 you removed the stopper the air above the tube 
 
388 STUDIES IN SCIENCE 
 
 pushed the water down into the pan. The air is 
 pushing with the same force upon the surface of the 
 water in the pan. As long as the tube was closed 
 at the top the air could not exert any direct force 
 upon the water, so the pressure of the air upon the 
 surface of the water in the pan held the column of 
 water up in the tube. If this is true, then air must 
 have weight. If you had an air-pump and a bottle 
 with a stopcock, you could prove by experiment that 
 this is true. Air does not weigh very much. A cubic 
 foot of air weighs about 534 grains. But when a 
 column of air several hundred feet high presses down 
 upon the earth, or upon bodies on the earth, even 
 this relatively light weight gives it considerable force 
 or pressure. Scientists have found by experiment 
 that the pressure of the air near the level of. the sea 
 is about 15 pounds per square inch. 
 
 Experiment 4. Do you think you could find a tube 
 so long that the air pressure could not hold the water 
 to the top of it? You can answer this question by 
 using mercury instead of water. Fill the small tube 
 full of mercury and invert it in a dish of mercury. 
 What happens? Why did some of the mercury flow 
 out? Why did it stop after a certain amount had 
 flowed out? With a meter stick or yard ruler meas- 
 ure the height of the column of mercury in the 
 tube. Since mercury is 13% times as heavy as water, 
 
AIR 
 
 389 
 
 how high a column of water would the air hold up? 
 How high is the column of air that is balancing the 
 column of mercury! Fasten the tube of mercury 
 to the rod of a burette stand or some other support 
 and allow it to stand in the room for a number of 
 days. Measure the column twice 
 every day. Can you explain why it 
 varies ! What name may you give to 
 this simple instrument that enables 
 you to measure air pressure! 
 
 Explanation. Some of the mer- 
 cury flowed out of the tube into 
 the dish because the air pressure 
 was not sufficient to hold it all up. 
 When the weight of the column of 
 air and of the mercury were just 
 the same the mercury ceased to flow 
 out. You can think of the air and 
 mercury columns as a pair of bal- 
 ances with the weight on each side 
 exactly equal. The column of air 
 has exactly the same cross-section 
 area as that of the mercury, but it 
 is as high as the air extends above the earth. 
 Fig. 65. 
 
 Uses of the barometer. If something causes the 
 air to become lighter, the mercury goes down. If 
 
 Air sup- 
 ports a column of 
 mercury 30 inches; a 
 column of water 34 
 feet. 
 
 See 
 
390 
 
 STUDIES IN SCIENCE 
 
 the air becomes heavier, the mercury rises or is 
 pushed up. You have really made a simple baro- 
 meter with which you may measure the 
 pressure of the air. If there is a barome- 
 ter in the building, study it and compare 
 with your simple one. You will find that 
 it is made on exactly the same principle. 
 It has, however, a fixed scale that enables 
 you to read the height of the column very 
 accurately. 
 
 You probably wonder why the air pres- 
 sure varies from day to day. The chief 
 cause of variation is due to different 
 amounts of water vapor. Water vapor is 
 lighter than the other gases of the air. 
 When there is a large percentage of it 
 present, the air is light. When there is 
 little moisture, the air is heavy. A low 
 barometer then indicates more moisture 
 and the likelihood of storms ; while a high 
 barometer indicates a dry atmosphere and 
 fair weather. 
 
 Since air pressure is due to the weight 
 of the air, where will air on the earth 
 exert the greatest pressure! You can 
 think this out by placing all your books 
 in a pile on your desk. Which one of the 
 
 Fig. 72. A 
 standard mer- 
 curial barom- 
 eter. 
 
AIR 
 
 391 
 
 books has the greatest pressure upon it I In pre- 
 cisely the same way the lowest part of the air has 
 the most pressure, because of the weight of all the 
 rest of the air above it. If you should take a baro- 
 meter to the top of a high mountain, would the mer- 
 cury go up or down? Why? If you lived one thou- 
 sand feet above sea level, and you should take a baro- 
 meter down to the sea, would the mercury go up or 
 down? Why? Scientists know exactly how much 
 the barometer falls with each foot of ascent at a 
 given temperature, so a barometer may be used to 
 determine how far 
 above sea level any 
 point is located. 
 
 Air pressure and 
 pumps. Place one end 
 of a glass tube open at 
 both ends into a glass 
 of water. Slowly suck 
 the air from the tube. 
 What happens? What 
 
 Fig. 73. A common suction pump 
 showing piston, valves, etc. 
 
 forces the water into the tube? You no doubt see 
 that as you remove the air from the tube the down- 
 ward pressure on the water in the glass pushes the 
 water upward in the tube. This illustrates in a very 
 simple way what happens when you pump water with 
 a common suction pump. 
 
392 STUDIES IN SCIENCE 
 
 Study the parts of an ordinary pump. To what 
 is the handle attached? What does the rod do as 
 you work the handle? If possible, take the pump 
 apart and find what is fastened to the rod -at the 
 lower end. 
 
 Making a pump. If you are skillful, you can make 
 a miniature pump that will work exactly as the real 
 one does. 
 
 Procure a straight lamp chimney, two pieces of 
 cork, a glass tube, some pieces of thin leather and 
 some wire. Make a hole in one piece of cork and 
 fit the piece of glass tubing into this hole so that 
 the tubing will come just to the surface of the cork. 
 Over the hole place a thin piece of leather, fasten it 
 at one end with a small tack or pin. This cork 
 should fit closely into the lower end of the chimney. 
 Make a similar hole in the second cork and fasten 
 a piece of leather in the same way over the opening 
 at the lower end. Fasten a piece of wire into the 
 upper part of the cork. To this fasten a heavier wire. 
 This cork should be trimmed off so that it will move 
 easily up and down in the chimney, or it may be 
 wrapped with thin muslin so that it will fit the chim- 
 ney snugly. 
 
 You now have all the parts of a simple suction 
 pump. The chimney is the pump barrel or cylinder. 
 The cork that moves up and down is the piston and 
 
AIR 393 
 
 the wire with which you move it is the piston rod. 
 The tube at the lower end is the suction pipe. The 
 pieces of leather covering the openings serve as valves 
 that open or close. 
 
 Place the glass tube of the pump in a dish of 
 water. Pull the piston upward. What happens? 
 Now move the piston downward and watch. What 
 effect did the lifting of the piston in the first place 
 have upon the air in the cylinder? 
 
 A portion of the air was lifted up with the cylin- 
 der; hence the air pressure upon the water in the 
 pan was greater than that in the cylinder and pushed 
 the water upward through the lower valve. Watch 
 carefully everything that happens when you move 
 the piston downward. Why does the water move 
 upward through the upper valve and why does the 
 lower valve remain closed? 
 
 The pressure now is due to the force with which 
 you are pushing the piston downward. This force 
 of the water pushes upon the lower valve and holds 
 it down, but the same force causes the water to push 
 upward against the lower part of the piston, which 
 opens the upper valve arid gives the water a chance 
 to rush through and fill the cylinder. This is exactly 
 what happens when you pump water from a well. 
 You can see the piston rod which is attached to the 
 handle moving up and down in the cylinder. The 
 
394 STUDIES IN SCIENCE 
 
 valves are at the lower part. The pipe extends down 
 into the water of the well. 
 
 There are some other kinds of pumps but all of 
 them are dependent upon air pressure to do their 
 work. 
 
 The vacuum cleaner. The vacuum cleaner used in 
 the home is a good illustration of air doing work. 
 Study a vacuum cleaner. What are the main parts! 
 How does it succeed in taking the dust out of 
 rugs, etc.! 
 
 You find three chief parts to any vacuum cleaner 
 whether it is large or small, whether it is run by 
 hand or some other power. 
 
 1. A tube or barrel. 
 
 2. A piston that works in the tube. 
 
 3. A nozzle, with a small opening, by which the 
 suction as it passes over the surface of objects is 
 increased. 
 
 When you move the piston the air in the tube is 
 pushed upward and escapes through a small hole in 
 the upper part of the tube. The tube below the 
 piston is almost emptied of air, so the heavier out- 
 side air rushes in carrying dust and other bits of 
 dirt with it. The nozzle simply defines a definite 
 space from which the air rushes in and from which 
 all dust and dirt are soon cleared. 
 
 Other uses of air. Think of other ways in which 
 
AIR 395 
 
 air is controlled by man so as to aid in doing work. 
 Among these is the windmill which is constructed 
 in a way to make air pump water. If you have a 
 bicycle, you pump the tire full of air. Tires of auto- 
 mobiles are filled with compressed air. Compressed 
 air is used in some places to run machinery. 
 
 Air and health. All life is dependent upon air. It 
 is of the greatest importance to have plenty of pure 
 air in our homes and schools. Pure air contains 20 
 per cent of oxygen, and does not have many dust 
 particles floating around in it. The dust particles 
 in air are of two kinds, dead dust and living dust. 
 The former consists of bits of soil, ash, lint from 
 clothing, and the like. This in itself is not really 
 harmful unless there is a vast amount of it present. 
 In that case it irritates the mucous membrane of the 
 nose, throat and lungs, and thus weakens their re- 
 sistance against disease germs. 
 
 Live dust consists of living organisms so small 
 and light that they easily float about in the air by 
 themselves, or more often upon the dead dust parti- 
 cles. They consist of spores of mold and other lower 
 plant forms, and bacteria of various kinds, some 
 harmless but others that produce human diseases. 
 
 Air in houses where people are living and work- 
 ing and where fires are burning is likely to become 
 very impure unless care is taken to see that fresh 
 air has a chance to come in. 
 
396 STUDIES IN SCIENCE 
 
 What provision for ventilation is made in con- 
 nection with the heating of your home or school 
 room? Is the warm air that enters the room through 
 the register pure? You can answer this question 
 by going back to the furnace and tracing the cold 
 air duct to its source. Does the air come from out- 
 of-doors or from some room in the house? In many 
 homes you find the cold air register in the hall. 
 When this is the case great care should be taken 
 to see that the air in the hall is kept as pure as pos- 
 sible. This can be done by keeping the hall window 
 slightly open. When the cold air register is in the 
 living or dining room, these rooms should be flushed 
 with fresh air several times during the day by throw- 
 ing open windows and doors. 
 
 Homes heated by hot water, steam or stoves are 
 usually ventilated by means of doors and windows. 
 A few buildings have special air shafts through 
 which the impure air may be carried out of the rooms. 
 In ventilating any room you must consider two things : 
 1. A place for the entrance of pure air. 2. A place 
 for the exit of impure air. This means that there 
 will be currents of air in the room. In fact, no room 
 can be ventilated unless the air is in constant motion. 
 If an opening is provided for the escape of impure 
 air, plenty of fresh air will come in around doors and 
 windows. An open grate or fireplace, though very 
 
AIR 397 
 
 wasteful of heat, provides one of the best means of 
 ventilating homes. The burned gases with air from 
 the room pass up the chimney. Fresh, outside air 
 pushes into the room through every crack and crevice. 
 A stove, though not so good as a grate, serves some- 
 what the same purpose. 
 
 Experiment. What happens when you breathe? 
 
 You probably know that your breathing organs con- 
 sist of the nostrils, trachea or windpipe, and lungs. 
 Place your hands on the upper part of your chest 
 with the tips of the second fingers touching each 
 other. Now inhale, filling your lungs. Then exhale. 
 Note what takes place in each case. Place your hands 
 at your sides just above the waist line with the 
 finger tips touching as before. Inhale and exhale, 
 watching the movements. Watch the shoulders of 
 some of your classmates, noting the breathing move- 
 ments. 
 
 Respiration. These observations show that when 
 you inhale the chest moves outward and upward, the 
 ribs outward and the shoulders upward. The dia- 
 phragm, which is a muscular partition between the 
 chest cavity and the abdominal cavity, moves down- 
 ward. All these movements make the chest cavity 
 larger, and, since the air that is in the lungs spreads 
 out to fill the increased space, the air pressure in the 
 lungs is less than that outside, so the air rushes in till 
 
398 
 
 STUDIES IN SCIENCE 
 
 the lungs are filled with air of the same pressure as 
 that outside. When you exhale, the ribs move inward, 
 the chest and shoulders downward, so that the cavity 
 
 bi 
 
 Fig. 74. L, Front view of the larynx; T, Trachea; B, Bronchial 
 tubes; bt, Bronchioles. 
 
 is made smaller and the air is pressed or pushed out 
 through the trachea and the nostrils. 
 
 In the iungs the air that is inhaled mixes with 
 
AIR 399 
 
 the air that is already there and in this way a fresh 
 supply of oxygen is brought in. The oxygen, how- 
 ever, to be of use must not remain in the lungs. It 
 passes through the thin walls of little air sacs in the 
 lungs, then through the walls of the small blood 
 tubes into the blood. 
 
 If you could see the structure of a lung, you would 
 find that the trachea divides into two branches called 
 bronchi, one is a bronchus. These divide and sub- 
 divide into smaller and smaller tubes until finally 
 each one ends in a tiny air sac made of thin mem- 
 brane. It is from these little sacs that the oxygen 
 passes into the blood. See Fig. 74. 
 
 The blood is composed of a thin watery fluid called 
 plasma, and a great number of tiny floating bodies 
 in this called corpuscles. Most of the corpuscles are 
 reddish in color, a few larger ones are white. The 
 white corpuscles are the purifiers of the body. 
 They carry off and destroy disease germs and in 
 other ways keep the body in good condition. The 
 red corpuscles absorb oxygen from the air in the air 
 sacs of the lungs and carry it to all parts of the body 
 where it is needed. It is needed wherever there is work 
 of any kind going on, or where heat is produced. 
 To do its work, the oxygen leaves the red corpuscles 
 of the blood and enters the cells of the tissues. Here 
 it unites with the carbon that the cells have absorbed 
 
400 STUDIES IN SCIENCE 
 
 from the food. The result of this union is that energy 
 is produced and heat is generated. You see that 
 heat is produced in precisely the same way as when 
 carbon from wood or coal unites with oxygen in a 
 stove or furnace, only in the body there is no accom- 
 panying flame or light, so we call the process oxida- 
 tion instead of combustion. The union of the oxygen 
 and carbon produces a compound called carbon 
 dioxide, which is a waste product. This is taken into 
 the lymph, then into the plasma of the blood and 
 carried back to the lungs where it passes into the air 
 sacs and is carried out with the breath. 
 
 Circulation. The relation of the blood and oxygen 
 in the body is most interesting. All the blood from 
 the lungs, with its load of oxygen, is collected into 
 four large tubes or blood vessels called the pulmon- 
 ary veins, which enter the left auricle of the heart. 
 The heart has four compartments or chambers known 
 as the right and left auricles and the right and left 
 ventricles. The blood that enters the left auricle is 
 what is ordinarily called pure blood; that is, it has 
 a large amount of oxygen in the red corpuscles. From 
 the left auricle the blood flows downward into the 
 left ventricle. This ventricle contracts. That is, the 
 walls grow thicker, come close together, and squeeze 
 the blood out. It is prevented from going back into 
 the auricle by valves between the two chambers which 
 
AIR 401 
 
 are closed by the force of the blood flowing against 
 them as the ventricle contracts. These valves act on 
 the same principle as the valve in the ordinary pump. 
 The blood is pushed into a large thick-walled artery 
 called the aorta. From here it goes all over the 
 body in tubes which branch out from the aorta. All 
 these tubes are called arteries. 
 
 Put your fingers lightly on the sides of your throat. 
 You can feel the pulsation of the two arteries which 
 go to the head. At the wrist you can feel one of the 
 branches that extends down the arm. The blood 
 from the heart does not flow into the aorta in a steady 
 stream, but in one impulse after another. The ven- 
 tricle contracts and forces the blood out, then it 
 relaxes and there is a pause. The blood would flow 
 back into the heart at this time if there were not 
 valves in the aorta to prevent it. This contraction 
 and relaxation of the heart is the beat that you can 
 feel. It also causes the pulse of the arteries, for the 
 walls are elastic and expand and relax with the 
 movement of the blood from the heart. 
 
 The arteries grow smaller and smaller toward the 
 extremities of the body. Finally they break up into 
 very small tubes called capillaries. These are so 
 numerous that you can not pierce your finger or any 
 other part of the body with the finest needle without 
 breaking several of them. It is in the capillaries 
 
402 STUDIES IN SCIENCE 
 
 that the oxygen passes out of the corpuscles into 
 the cells. It is here, too, that the food which is car- 
 ried in the blood flows out to feed the cells. 
 
 The capillaries unite and form small veins; these 
 unite again and again, growing larger and larger 
 until in the inner portion of the body there are very 
 large veins. You can see the veins and their branches 
 near the surface in your hands and arms. At last 
 all the veins in the upper portion of the body unite 
 into one large vein near the heart, and all in the 
 lower part unite into another large vein. The upper 
 one is called the descending vena cava, the lower 
 one the ascending vena cava. These empty the blood 
 into the right auricle of the heart. From here the 
 blood goes into the right ventricle. The right ven- 
 tricle contracts at the same time the left one does 
 and sends the blood through the large pulmonary 
 artery to the lungs. This blood, since it comes from 
 all over the body, contains a large amount of waste 
 products, especially carbon dioxide, which is given 
 up to the air in the lungs and carried out with the 
 breath. 
 
 Hygiene of breathing. From your observation of 
 breathing movements it must be evident that if you 
 fill all the air spaces in your lungs you must enlarge 
 the chest cavity sufficiently to allow every portion 
 of the lungs to expand. If clothing is worn too tight 
 
AIR 403 
 
 about the waist, the movements of the ribs and dia- 
 phragm may be impeded and healthful breathing 
 prevented. Out-door exercise causes rapid breath- 
 ing and fills the lungs with pure air. If you do not 
 take much out-door exercise it is a good plan to 
 practice deep breathing at least twice each day. In 
 the morning when you arise stand close to an open 
 window or door and inhale as deeply as you can, 
 then exhale promptly. Do this at least ten times. 
 Do the same thing in the evening before you retire, 
 when all your tight clothing has been removed. 
 Another excellent habit to form is to breathe deeply 
 as you walk along to school. Inhale while you take 
 eight or ten steps. Then exhale either quickly or 
 slowly. Repeat this ten or twelve times and you 
 will feel the invigorating effects. 
 
 It is quite as important to have plenty of pure air 
 during the night as during the day. This can be 
 secured by keeping the windows in the sleeping room 
 open all night, all the year around. Many people 
 are building outside sleeping porches in order to 
 sleep in pure air. 
 
 Diseases of the breathing organs. The diseases 
 that commonly affect the breathing organs are colds, 
 grippe, tuberculosis, and pneumonia. All of these 
 are caused by disease germs or bacteria. Persons 
 who have these diseases may scatter the germs by 
 
404 STUDIES' IN SCIENCE 
 
 ordinary breathing, but especially by coughing, sneez- 
 ing and spitting. The germs fly around in the air 
 and are inhaled by well persons. If a person is in 
 excellent health, the white blood corpuscles may at 
 once kill off the germs and he will feel no ill effects. 
 On the other hand, the bacteria may get a foothold, 
 begin to grow and multiply and bring on disease, at 
 once or in a short time. 
 
 If all people who have these diseases were very 
 careful not to scatter the germs, there would soon 
 be none of them to spread. When you have a cold 
 you should keep away from other people as much as 
 possible. When you cough or sneeze you should 
 hold a handkerchief over your mouth and nose. In 
 no case should you spit upon the sidewalk or about 
 the house. Tuberculosis is probably spread more by 
 the habit of spitting than in any other way. 
 
 Clean air means clean homes, clean streets, clean 
 alleys, clean clothing, and clean bodies. Since air is 
 constantly moving, bits of dust with germs are con- 
 stantly being carried around for people to inhale. 
 Out-of-doors the air changes so constantly that there 
 is little danger. But indoors the air may become 
 so laden with germs that every breath carries some 
 into the body. 
 
 To keep dust out of the home and school, then, 
 is one of the ways to aid in preventing disease. Rugs 
 
AIR 405 
 
 on the floors that may be taken out-of-doors fre- 
 quently and cleaned, vacuum cleaners that prevent 
 dust from being scattered, oiled cloths for dusting, 
 all help to keep the air pure. 
 
 Moisture in the air. Another thing that we should 
 give attention to is the amount of water vapor in the 
 air, as the heated air of our homes is usually too dry 
 for health. More moisture should be supplied. With 
 steam or hot-water systems, vessels of water should 
 be placed on or under the radiator so that moisture 
 may constantly evaporate from them. What provi- 
 sion does a hot air furnace make for a constant sup- 
 ply of moisture in the air? Look at the side of the 
 furnace for a small water pan. This opens into the 
 jacket. Water in this pan evaporates and the vapor 
 is carried with the warm air into the rooms. 
 
CHAPTER XXIV 
 
 WEATHER 
 
 Materials. A thermometer, an almanac, daily 
 weather maps, pages in your notebook to keep weather 
 and sun records. Weather maps may be obtained 
 by teachers for use in schools from the Weather 
 Bureau at Washington or from the nearest weather 
 station in the state. 
 
 Study. If you try to decide what the term weather 
 means you will find that it includes many things 
 that you have studied in the last three chapters. 
 It means certain conditions of the atmosphere 
 with reference to temperature, moisture and wind. 
 Have you ever thought how closely the weather 
 touches the lives of all people? Farmers, gardeners, 
 and fruit growers are largely dependent upon the 
 weather for success or failure in raising their crops. 
 Weather conditions more than anything else caused 
 primitive man to erect shelters from which have 
 finally evolved our well-arranged, comfortable homes. 
 Clothing, too, to a large extent, originated because 
 man needed protection from the weather. Even now 
 the weather has much to do with the kind of clothing 
 
 406 
 
WEATHER 
 
 407 
 
 that is used during the different seasons. In fact, it 
 will not be hard for you to make a long list of indus- 
 tries and customs that exist because of weather. 
 
 Man cannot control the weather, but by informing 
 himself about the laws that govern winds and storms, 
 and by keeping in touch with the information sent 
 out by the Weather Bureau, he can usually plan his 
 activities in a way to prevent the weather from 
 injuring his crops or other work. 
 
 A good way to find out facts about the weather 
 is to keep a weather record for a period of days or 
 weeks. Place in your notebook or on a large piece 
 of paper the following outline arid keep the record 
 for a month or longer. If you have no barometer 
 leave out the column for pressure. 
 
 WEATHER RECORD 
 
 
 
 Tem- 
 
 Wind 
 
 Wind 
 
 
 
 
 Precipita- 
 
 
 Date 
 
 Hour 
 
 per- 
 
 Direc- 
 
 Veloc- 
 
 Pressure 
 
 Sky 
 
 tion or 
 
 Remarks 
 
 
 
 ature 
 
 tion 
 
 ity 
 
 
 
 rainfall 
 
 
 Dec. 
 
 9 a. m. 
 
 warm 
 
 t 
 
 Light 
 
 29.5 in. 
 
 cumulus 
 
 
 Foggy 
 
 
 
 60* 
 
 
 
 
 clouds 
 
 
 this a. m. 
 
 Note to teacher: Weather observations and records should be- 
 gin in the fall not later than November and be continued at least 
 a week at a time until you are ready to take up the regular study 
 after the chapters on heat, water and air. The record may be kept 
 without interfering with the other studies. 
 
408 STUDIES IN SCIENCE 
 
 These observations may be taken without instru- 
 ments. However, if the school has a thermometer 
 the temperature should be reported in degrees. If 
 there is no thermometer then the terms warm, hot, 
 very hot, chilly, cold, or very cold may be used. 
 
 The direction of the wind may be indicated by an 
 arrow. An arrow pointing toward the top of the 
 page indicates that the wind is traveling north. Is a 
 wind named from the direction it is going or the 
 direction from which it is coming! Velocity means 
 the distance the wind travels per hour. The follow- 
 ing words may be used to indicate velocity. These 
 terms are suggested by the U. S. Weather Bureau. 
 Calm, when there is no perceptible wind; light, when 
 there is just enough wind to move the branches of 
 the trees ; brisk, when only branches sway ; high, when 
 whole trees sway. 
 
 Under sky, report whether it is clear, partly cloudy, 
 or overcast, and the kind of clouds. Precipitation 
 means falling weather of any sort rain, snow, hail, 
 etc. Under remarks, report any item of interest that 
 does not appear under the other headings. Thus, 
 for December 3, a heavy frost last night, or for 
 December 16, a slight snow fell this afternoon. 
 
 At the end of the month make a short summary 
 derived from your observations. How many fair 
 days! How many cloudy? How many in which 
 
WEATHER 
 
 409 
 
 there was precipitation? What was the general 
 direction of the wind when the temperature was 
 warmest? When the temperature was coldest? From 
 what direction did the rain come? From what direc- 
 tion did the snow come? What was the direction 
 of the wind during the cloudy weather, etc.? 
 
 Temperature. Your record will show some inter- 
 esting facts concerning temperature, especially if 
 your observation extends over a period of several 
 months. Usually the temperature is lower in the 
 morning than in the evening. It is highest early in 
 the afternoon. One day may be very cold; the next 
 from thirty to forty degrees warmer. Sudden changes 
 in temperature are dependent upon wind direction 
 and velocity, but the more constant changes through- 
 out the day and from month to month are due to the 
 relative positions of the earth and sun. 
 
 Arrange the following outline in your notebook. 
 Make observations twice each week for a period of 
 two or three months. The best time to begin is in the 
 latter part of November or early in December. 
 
 SUN OBSERVATIONS 
 
 Date 
 
 Sunrise 
 
 Altitude of 
 Sun at Noon 
 
 Sunset 
 
 Time 
 
 Position 
 
 Time 
 
 Position 
 
 
 > 
 
 
 
 
 
410 STUDIES IN SCIENCE 
 
 To get the time of sunrise and sunset consult an 
 almanac. This is more accurate than getting it by 
 observation. Use great care in getting the position 
 of the sun. In the first place try to find a spot from 
 which you can see the sky down to the horizon. In 
 the morning at sunrise or soon afterward stand fac- 
 ing due east. Is the sun north or south of that point! 
 Now turn facing due south. How many degrees are 
 there on the horizon between due east and due south! 
 
 Every circle no matter how large or how small has 
 exactly 360 degrees in it. Since from the point due 
 east to due south is one-fourth the distance around 
 the circle of the horizon, it is, of course, 90 degrees 
 between these two points. 
 
 Now face the sun and decide whether or not it is 
 half way between east and south. If not, how many 
 degrees south of east is it! Estimate as accurately 
 as you can the number of degrees. Fix the position 
 in relation to some object as a tree, telephone post, 
 or building. Note carefully by means of this object 
 whether or not the sun remains in the same position 
 week after week. If it does not, determine which 
 way it is moving. 
 
 Make the same kind of observations to determine 
 the varying positions of the sun at sunset. 
 
 At noon stand out-of-doors where you can see the 
 sun and sky. The point directly over your head is 
 
WEATHER 411 
 
 called the zenith. Now face the south. Trace with 
 your eye the curved line of the sky from your zenith 
 to the point in the southern horizon directly in front 
 of you. How many degrees is it I 
 
 Now determine the position of the sun on this line. 
 How far above the horizon does it seem to be? Is it 
 half way to the zenith? Fix its position with refer- 
 ence to some object and determine from week to week 
 whether it is getting lower or higher. The distance 
 the sun is above the horizon is called its altitude. 
 
 You can make a simple instrument with which to 
 measure the exact altitude of the sun at noon. This 
 instrument is called a clinometer. To make a clinom- 
 eter use a square of cardboard or pasteboard. On 
 this draw a quarter of a circle to represent the line 
 from the zenith to the horizon. Mark this off into 
 degrees from zero to ninety. Mark off the ninety into 
 eighteen equal parts. Each part is five degrees. Now 
 divide these into one-degree spaces. Tack the paste- 
 board onto a board and drive a nail a short distance 
 into it at the square corner. Fasten the board a few 
 feet from the ground on the east or west side of the 
 house at the south end, so that the sun will shine upon 
 it at noon. The shadow cast by the nail will fall upon 
 the scale indicating the altitude of the sun. In mak- 
 ing the clinometer you should know on which side of 
 the house it is to be placed. If it is on the east side. 
 
412 
 
 STUDIES IN SCIENCE 
 
 put the zero at the upper right-hand corner of the 
 scale; if on the west, begin the scale at the upper left- 
 hand corner. 
 
 Discussion. 'Your observations show that before 
 December 22 the sun is moving farther southward 
 both morning and evening. It also shows that its 
 altitude is lower. After this date it moves north- 
 ward and at noon its altitude is higher. 
 
 Fig. 75. The amount of heat received depends upon the angle at 
 which the sun's rays strike the surface of the earth. The same num- 
 ber of rays fall on a smaller area at A than at B. 
 
 It is this movement of the sun that brings the sea- 
 sonal weather changes. When the sun is far to the 
 south its rays strike the earth with a greater slant 
 than when it is farther north and higher at noon. 
 This means that slant rays do not have as much power 
 to heat the earth as those that are more nearly 
 vertical. 
 
 A study of Fig. 75 will explain the reason for this. 
 
WEATHER 413 
 
 The two sets of parallel lines represent the same num- 
 ber of heat rays from the sun striking the earth. With 
 your ruler measure the difference in space covered by 
 each set. Since A covers a much less space it can, of 
 course, heat the portion that it strikes much more than 
 if it were spread out to cover a space as large as B. 
 Hence the slanting rays of winter cannot heat the 
 earth as much as the more vertical rays of summer are 
 able to do. The same is true during each day. The 
 slanting rays of morning and evening do not have the 
 same power to heat as the more vertical rays of noon. 
 
 Nooh 
 
 g. 76. Diagram, showing the difference in the angles at which 
 the sun's rays strike the earth at sunrise, noon, and sunset. 
 
 You already know that the rays of heat from the 
 sun called radiant heat are absorbed by the earth. 
 The air near the earth is warmed, not directly from 
 the sun but from the earth, partly because it touches 
 the warm earth and partly because heat from the 
 earth radiates into the air. When the heat rays of 
 the sun strike certain objects on the earth the heat 
 instead of being absorbed is reflected back into the 
 air. From this vou can easilv see that the air near 
 
414 STUDIES IN SCIENCE 
 
 the earth is much warmer than the air higher up. 
 Some tests have been made that show the temperature 
 from 12 to 15 degrees colder at a height of one mile 
 above the earth and from 70 to 80 degrees colder 
 five miles from the ground. 
 
 Clouds. If you have never formed the habit of 
 observing the clouds you will find their study won- 
 derfully interesting. The sky, like the sea, has endless 
 variations which are due mostly to cloud forma- 
 tions. As you already know, clouds are masses of 
 condensed water vapor floating in the air. Some- 
 times these masses are very low, not more than one- 
 fourth of a mile above the earth. Sometimes they 
 are six or seven miles high. They vary in appear- 
 ance with their height, size, density and amount of 
 rain in them. The names given to the most common 
 cloud forms are cirrus, cumulus, stratus, and nimbus. 
 Cirrus are light, feathery clouds that are high in the 
 sky. Sometimes they are mere white streaks across 
 the blue. These clouds rarely indicate an approach- 
 ing storm. However, when they look like plumes 
 with torn and frayed edges and are moving rapidly 
 and gathering into larger masses, rain or snow is 
 usually indicated. 
 
 Cumulus is the great mass of clouds so familiar in 
 the summer time. Like great mountains with rounded 
 tops, sometimes they are glistening white all over, 
 
WEATHER 
 
 415 
 
 Fig. 77. Forms of clouds: I. Cirro-cumulus, often called a mack- 
 erel sky. II. Stratus, seen most frequently near the horizon before 
 or after sunset. Cumulus clouds sometimes form in straight lines 
 and are called cumulo-stratus. III. Cirrus; high, fringy clouds that 
 seldom predict a storm. IV. Cumulus; when large often changing 
 to nimbus, producing a sudden storm. 
 
416 STUDIES IN SCIENCE 
 
 sometimes white on one side and dark on the other. 
 Often they float around during the morning, then 
 break up and disappear. When they do this they 
 are called dry weather clouds. Sometimes they col- 
 lect together growing larger and darker. When this 
 is the case they usually bring a thunder shower. When 
 they reach this stage they are called cumulo-nimbus. 
 
 Stratus are the clouds that appear as layers across 
 the sky. Light ones are often visible at sunset and 
 sunrise. They are also seen at other times during 
 the day. Any cloud that 'has no special form but 
 spreads out like a sheet or in layers is a stratus cloud. 
 
 Nimbus is a cloud from which precipitation is occur- 
 ring; hence any of the- other forms change to nimbus 
 as soon as they begin to fall in the form of rain or 
 snow. 
 
 Sometimes you will see rather high in the sky a 
 wavy mass of white clouds which look like white 
 curly wool. This is a combination of cirrus and 
 cumulus known as cirro-cumulus. It is also spoken 
 of as a mackerel sky. You will find other apparent 
 combinations as strato-cumulus and cirro-stratus; 
 high, white, leathery clouds in layers. 
 
 By watching the clouds every opportunity you have 
 you will soon learn to recognize the different forms 
 and be able to tell somewhat accurately what clouds 
 are likely to bring rainfall. 
 
WEATHER 417 
 
 Winds. Your study of convection currents tells 
 you how wind is produced. It is nothing but a move- 
 ment of air due to unequal pressure. The unequal 
 pressure is caused chiefly by a difference in tempera- 
 ture. Heat makes the air expand and become light, 
 The heavy air rushes toward the light area and the 
 result is wind. All the winds on the earth's surface 
 are caused in this way. You can see why there are 
 constant winds blowing toward the heat equator from 
 the north on one side and from the south on the other. 
 The movement of the earth on its axis changes the 
 course of these constant winds so that north of the 
 equator they blow from the northeast instead of from 
 due north, and south of the equator they blow from 
 the southeast. These are known as trade winds. 
 
 Just as in a room the warm air from a radiator 
 or stove is pushed upward, moves outward at the 
 ceiling, becomes cooler and drops downward in parts 
 of the room most remote from the stove, so on the 
 earth at the equator the heated air moves upward, 
 and when it reaches a certain height it spreads out, 
 cools, and drops down to the earth again. We live 
 in the part of America north of the region where the 
 air drops downward. It spreads out toward both the 
 north and south. We are in the northern belt. The 
 deflection due to the turning of the earth upon its axis 
 causes the air to move eastward, so we have what 
 
418 STUDIES IN SCIENCE 
 
 are known as the westerly winds. They do not blow 
 steadily eastward as you know. They are influenced 
 by mountains and valleys and by local differences in 
 temperature and pressure. We have constantly mov- 
 ing across the United States from west to east what 
 are called "lows" and "highs." A low is an area 
 of low air pressure, a high of heavy air, or high 
 pressure. 
 
 In a low the air is moving from all sides toward 
 the center. In a high it is moving from the center 
 outward on all sides. The kind of weather we have 
 depends largely upon whether a low or a high is 
 passing over or near us. This movement is shown 
 on a weather map. 
 
 Weather map. Study a weather map. Make a list 
 of everything you find on it. Study the explanation 
 given in fine print in the lower corner. This will 
 enable you to interpret all the terms and symbols 
 used. Trace a low as it moves eastward for several 
 days and decide whether it brings fair or stormy 
 weather. Trace several isotherms into a low to see 
 in which part of the low the highest temperature is 
 found. The isotherms are the dotted lines and con- 
 nect places having equal temperature. In the same 
 way trace the isobars. These are the solid lines. 
 They connect places having equal pressure. 
 
WEATHER 
 
 419 
 
 Weather maps are made under the direction of the 
 Weather Bureau at Washington, D. C. The first 
 weather observations for the public were begun in 
 
 |r 
 
 1 
 
 . ' l'-;,ill!! 
 
420 STUDIES IN SCIENCE 
 
 1871. The Weather Bureau became a definite part 
 of the Department of Agriculture in 1891. The daily 
 map gives definite facts concerning temperature, pres- 
 sure, wind direction, velocity and rainfall all over 
 the United States. When you learn to read one of 
 these maps you can tell what kind of weather people 
 are having in any part of the country. More than 
 that, you can tell by the position of the lows and the 
 direction they are moving what kind of weather you 
 are likely to have during the next twenty-four hours. 
 The weather forecast found on the map and printed 
 in newspapers is made from a study of the weather 
 jnap by men who are employed by the Weather 
 Bureau. 
 
 Information for the making of maps is obtained 
 from weather stations which are found in all parts 
 of the country. At these stations observations are 
 taken at 8 A. M. and again at 8 P. M. every day. 
 These are telegraphed to the Weather Bureau and 
 experts prepare the maps and send them out. Each 
 state has a weather bureau center which prepares 
 maps for its own region. 
 
 The value of warnings sent out by the Weather 
 Bureau to agriculturists and seamen is beyond esti- 
 mation. It is fair to state that property worth at 
 least $30,000,000 is saved annually in the United 
 States by the work of the Weather Bureau. 
 
SPRING STUDIES 
 
 CHAPTER XXV 
 
 POULTRY AND POULTRY PROJECTS 
 
 Material. Poultry of the neighborhood, feathers 
 and eggs. 
 
 Study. Make a list of all the different kinds of 
 poultry in your community. Which kind is raised in 
 greatest numbers! Do many people keep just one 
 breed? How many keep several breeds'? If you have 
 poultry at home, find out the number of each kind, 
 and estimate their present market value ti Among 
 your hens how many are more than one year old? 
 How many pullets? How many cocks? How many 
 eggs do you get daily? Try to discover by observa- 
 tion which are laying more, the pullets or the older 
 hens. 
 
 Study of a chicken. Chickens, and all other poul- 
 try, are birds, and as members of that great group 
 of animals they have certain characteristics. 
 
 Organs of locomotion. Note the feet. Are they 
 placed near the front or the back part of the body? 
 How many toes are there? Compare with one 
 another as to length. How many are actually used in 
 walking? What is found at the end of each toe? Do 
 
 421 
 
422 STUDIES IN SCIENCE 
 
 hens wajk on their toes or on the soles of their feet? 
 What protective covering has the foot! Why are 
 scales a better covering for the feet and toes than 
 feathers ? Look for chickens that have feathers on 
 their feet. Try to find out how the toes hold the 
 chicken on the perch. What other use is made of 
 the feet than walking? 
 
 Watch a hen fly and note the movement 
 of the wings. Spread out a wing and study the ar- 
 rangement of the feathers. When the wing moves 
 downward does the air pass between the large feath- 
 ers? In what direction does the chicken move with 
 the downward stroke of the wing? 
 
 At your first opportunity look at the bones of a 
 chicken's wing and compare with those of your arm. 
 
 Watch the flight of wild birds. What use is made 
 of the tail? 
 
 Procuring food. Watch a hen feeding. What is 
 the chief organ that she uses? Describe the beak or 
 bill and state what characteristics it has that fit it 
 for its purpose. Is it hard or soft; sharp or blunt? 
 To what extent does it differ in different breeds of 
 chickens? Name the different kinds of food you 
 have seen hens eating, and the different ways of 
 using the beak. Is the food chewed or swallowed at 
 once? 
 
 Sense organs. Name all the sense organs you can 
 

 POULTRY AND POULTRY PROJECTS 
 
 423 
 
 find on the head of a chicken. Note the position, 
 shape and color of the eyes. Can the hen see the 
 same object with both eyes at the same time? Look 
 for eyelids. If you have a tame hen that you can 
 hold in your arm, touch the head near the eye and 
 note what happens. Find the ears. Describe them. 
 What evidence have you that hens 
 and other birds hear well? Notice 
 the position of the nostrils, the 
 small openings on the upper part 
 of the bill. 
 
 Feathers. Make a collection of 
 all the different kinds of feathers 
 that are found on one chicken. 
 You should have one or more from 
 the tail, the back, breast, neck, 
 legs, and one from each of the dif- 
 ferent parts of the wing. These 
 will include the stiff outer wing 
 feathers, the primaries ; the row 
 of large feathers next to these, the 
 secondaries; and the finer, over- 
 laping feathers, the coverts. 
 
 Examine one of the tail feathers. How many 
 distinct parts do you find? What are the names of 
 the parts? (See Fig. 79.) Pull the barbs of the web 
 apart to determine how they are fastened together. 
 
 A 
 
 Fig. 79. Parts of 
 a feather. A, Quill; 
 B, Fluff; C, The web 
 composed of barbs. 
 
424 STUDIES IN SCIENCE 
 
 Compare the different feathers as to the amount of 
 web and fluff. Which have more fluff, the feathers of 
 the back or breast? Which of all the feathers have 
 the least fluff? Which the greatest amount? What 
 part of each feather is exposed to the weather? Look 
 closely to see how much of each web is exposed. What 
 is the value of this great overlapping? What is the 
 use of the undercoat of fluff? Place the tips of your 
 fingers close to the body in the fluffy part of the 
 feathers. Now place them on the outer part of the 
 web. Explain the difference in temperature. Eecall 
 what you learned about conductors and non-conduc- 
 tors of heat and decide in which class feathers 
 belong. 
 
 How does the hen succeed in keeping her feathers 
 smooth and in a condition to shed water? Watch one 
 oiling and preening her feathers. Where is the oil 
 gland situated? 
 
 Make a chart showing the different kinds of 
 feathers. 
 
 Other types of poultry. If you have an opportun- 
 ity make a comparative study of geese, ducks and 
 turkeys. Note the special adaptations of the bills, 
 feet and feathers of ducks and geese for life in or 
 near water. 
 
 Discussion. Some of the questions that have aris- 
 en with your study cannot be answered by observa- 
 
POULTRY AND POULTRY PROJECTS 425 
 
 tion. The characteristics that you have discovered 
 are in the main common to all birds and that gives 
 them an added interest. 
 
 Perhaps you are not certain that the chicken 
 walks on its toes. The segment that we often call 
 the lower part of the leg is really the foot. The 
 " drumstick " corresponds to your leg below the knee, 
 and the second joint to your thigh. When a bird is on 
 the roost the toes curve round the perch and the 
 weight of the body bends the joints and tightens the 
 sinews so that the bird sleeps without danger of fall- 
 ing. In fact, a perching bird has to rise up, straight- 
 ening its legs somewhat, before it can release its toes 
 from the perch. 
 
 The flight of birds is based upon a principle of 
 physics. The large primary feathers, when the wing 
 is spread, overlap to such a degree that no air passes 
 between them. The bird strikes downward with the 
 wing and the force exerted sends it forward and up- 
 ward just as a boat is sent forward when you strike 
 the water with the oar. The curved wing enables the 
 bird to press harder upon the air than if it were 
 straight. You noticed that the barbs on the front 
 edge of a large wing feather lie close and almost par- 
 allel to the quill. This prevents them from being 
 torn apart by the wind. With the up stroke the wing 
 is turned slightly sidewise and offers less resistance 
 
426 STUDIES IN SCIENCE 
 
 to the air. So while the down stroke pushes the 
 bird upward and forward, the up stroke does not 
 push the bird downward. The tail is spread in 
 flight and serves as a rudder to guide the bird. 
 
 The bill of a chicken is well adapted to procuring 
 food. It is sharp and strong and is used to break up 
 hard particles as well as to pick up the food. As 
 chickens have no teeth the food is swallowed whole. 
 First it passes into the crop where it is moistened, 
 then into the stomach where it is further moistened 
 with digestive fluids, and then into the gizzard where 
 it is ground up by small pebbles and other hard 
 substances. The bill is also used as a weapon of de- 
 'fense, to preen and oil the feathers, and to turn the 
 eggs during incubation. 
 
 The eyes of a chicken are closed by the lower lid 
 instead of the upper. There is a thin semi-transpar- 
 ent membrane, sometimes called the third eyelid, 
 present in the eyes of all birds. It spreads over the 
 eye like a veil and is a protection against strong 
 light and other injuries. 
 
 The ears are small irregular openings on the sides 
 of the head. Usually they are pretty well covered 
 with feathers. Although the external ear is so in- 
 conspicuous, birds possess a very keen sense of hear- 
 ing. 
 
 Breeds of chickens. If there are representatives of 
 
POULTRY AND POULTRY PROJECTS 427 
 
 different breeds of chickens in your neighborhood, 
 visit them, study their characteristics, and prepare 
 to report in class. Collect from poultry journals and 
 farm papers pictures of different breeds and make a 
 chart or booklet. 
 Poultry raisers group the breeds into four great 
 
 Fig. 80. The dual-purpose-type. 
 
 classes : egg breeds, meat breeds, dual-purpose, and 
 fancy breeds. 
 
 Egg breeds were originally European birds and 
 are known as the Mediterranean class. They are 
 small active chickens. The hens are noted for the 
 great number of eggs they lay and for the fact that 
 they rarely want to "sit." The most common va- 
 
428 STUDIES IN SCIENCE 
 
 rieties are Leghorns, Minorca, Black Spanish and Blue 
 Andalusian. 
 
 The meat breeds are known as the Asiatic class, be- 
 cause the original stock probably came from Asia. 
 There are three common varieties, the Brahmas, 
 Cochins and Langshans. They are very large, 
 heavy chickens and produce a large amount of meat. 
 They are not good layers and are of little value in 
 raising chicks. 
 
 The general purpose breeds are more popular in 
 most places than the others. They belong to the Amer- 
 ican class, because they have been produced by Ameri- 
 can breeders. They are medium in size and are com- 
 paratively good layers, hence they are useful in pro- 
 ducing both meat and eggs. They are also better 
 adapted than other breeds to raise and care for the 
 young chicks. The common varieties are the Ply- 
 mouth Eocks, Wyandottes, Rhode Island Reds, 
 Orpingtons, and Dominiques. 
 
 Compare the different breeds with each other as to 
 size, color, shape, and value. The fifth breed named 
 above is of little practical value. Occasionally some 
 one raises bantams or other fancy breeds for the 
 novelty of it. 
 
 Care of poultry. In caring for your poultry you 
 must consider: 1. Housing, 2. Feeding, 3. Arrange- 
 ments for producing chicks. 
 
POULTRY AND POULTRY PROJECTS 
 
 429 
 
 Housing. What different kinds of poultry houses 
 are there in your community? What points would 
 you consider in making a poultry house? 
 
 Size and shape of the house. The size and shape 
 are of some importance. The building should not be 
 too wide. Sixteen feet is wide enough. Many are 
 but twelve feet. The house should be large enough 
 so that each bird may have a floor space of from 
 five to six feet. A house twelve by twenty-four feet 
 
 Fig. 81. A good poultry house. 
 
 is about the right size for fifty hens, or perhaps six- 
 teen by sixteen gives better floor space for arranging 
 nests and roosts. 
 
 Connected with the poultry house there should 
 be a run where the chickens may get out into the 
 open air except in the most severe weather. 
 
 Light and air. It is very essential to have plenty 
 of sunlight in the house. The way to manage this 
 
430 STUDIES IN SCIENCE 
 
 is to have the building face the south with a number 
 of windows. A house sixteen feet long should have 
 two windows each containing eight square feet. Good 
 ventilation is as important as plenty of sunlight. A 
 way must be provided for exchange of air. Some 
 poultry houses are so open that while there is plenty 
 of fresh air, there are too many drafts. Many plans 
 have been tried for securing ventilation without 
 drafts. Probably the best method yet found is the 
 cloth window pane. This may be made of muslin or 
 cheese cloth and may be placed in one of the south 
 windows instead of glass. It may be so arranged that 
 during severe weather the glass window may partly 
 close the opening. 
 
 Dryness. Too much moisture is detrimental to the 
 health of poultry. This means that the building 
 should be placed on well drained ground. Some 
 poultrymen elevate the floor several inches with a 
 layer of gravel. On top of this is a cement floor. Ce- 
 ment makes an excellent floor. It is easy to clean 
 and at the same time keeps out rats. 
 
 Roosts. Eoosts should be comfortable, and 
 arranged so that cleaning may be easily done. There 
 are many different devices. Perhaps the most satis- 
 factory is to make the roosts out of two by two 
 lumber with the upper edges rounded. Place them 
 about two and one-half to three and one-half feet 
 
POULTRY AND POULTRY PROJECTS 431 
 
 from the floor. Under them place a platform to catch 
 the droppings. 
 
 Nests. Proper placing of the nests is a problem 
 of importance. Perhaps the most practical method is 
 to place the nests under the platform described 
 above. In this way the same floor space is used 
 for nests and roosts. Many poultry raisers prefer 
 to have platform, nests, and roosts movable, so that 
 they may be taken out, cleansed and disinfected. 
 
 Describe the nests you have seen. What size were 
 they? Were they placed in a strong light or in a 
 dim light? There are a number of different kinds 
 of nests. A nest should be from twelve to fourteen 
 inches square and from six io eight inches deep. It 
 should be shaded in some way from the strong light. 
 Hens seem to prefer a rather dark place for their 
 nests. 
 
 Feeding. Make a list of the different kinds of 
 poultry foods used in your district. .What grains 
 are fed? Are they used dry or moist? Whole or 
 ground? Chickens, like all other animals, need a 
 certain amount of starchy foods, or carbohydrates, 
 proteids, and fats. Laying hens require a large 
 amount of proteid food because the white of egg is 
 almost pure proteid. Every poultryman decides for 
 himself the exact amount of the different feeds to 
 give. Grain of some kind, part whole and part 
 
432 STUDIES IN SCIENCE 
 
 ground, is used by all. The whole grains should be 
 scattered in a layer of straw on the ground or floor 
 so that the chickens will be compelled to exercise in 
 order to get them. Meat scraps and sour milk 
 supply the proteid. Green food of some sort is quite 
 essential. This may be supplied by vegetables, such 
 as cabbage, 'beets, turnips, etc., and by grass, clover, 
 alfalfa and sprouted oats. Fine gravel or crushed 
 oyster shells should always be supplied, as these aid 
 the digestive process. Chickens require plenty of 
 clean water as well as food. The drinking pan should 
 be emptied and fresh water put in every day. 
 
 Chicks. How early in the spring do poultry rais- 
 ers set hens? Start incubator! If possible, visit a 
 a home where an incubator is used. Describe it. 
 How is the heat supplied? Can you trace the convec- 
 tion current from its source to the eggs? How warm 
 must the incubator be kept? The heat is usually 
 supplied by ,a small oil lamp or gas heater. When 
 the chicks are taken from the incubator how are they 
 kept warm? Different methods are employed, but 
 usually they are placed in a brooder, which is a 
 small box with strips of cloth among which the 
 chicks may cuddle down to keep w T arm. There are 
 many different kinds of brooders, some of which are 
 furnished with artificial heat. 
 
 The feeding of young chicks is of great importance. 
 
POULTRY AND POULTRY PROJECTS 433 
 
 For forty-eight hours after hatching the chick does 
 not require any food. The yolk of the egg furnishes 
 it food during this period. The first food may be 
 hard boiled eggs chopped fine, shell and all, mixed 
 with stale bread, cracked wheat or corn; or the first 
 meal may be stale bread crumbs moistened in milk. 
 After a few days the chick may be fed a mixture of 
 bran, corn-meal, shorts, and scraps of meat. Most 
 people prefer to use the food dry. Some poultrymen 
 cook all the food for the first few weeks. With dry 
 food plenty of milk should be used. Sour milk is 
 quite as good or better than sweet. 
 
 Value of poultry. Name all the different prod- 
 ucts produced by poul- 
 try. How important 
 are these products ? 
 What is the average 
 price of eggs? Of 
 spring chickens or 
 broilers per pound? 
 Of one-year old hens? 
 What is the price of 
 feathers? Poultry 
 products are becoming Fig> 82 A good type of hen 
 more and more important each year. The demand for 
 choice chickens and fresh eggs is constantly increasing 
 and the prices are high enough to make poultry 
 
434 STUDIES IN SCIENCE 
 
 raising a successful business. When is the price of 
 eggs highest? How may eggs be packed to ship by 
 parcel post? 
 
 Poultry projects. You should begin to think about 
 raising poultry on your own account if you live in the 
 country or in a town where you may have space 
 enough for a small house and run. Choose a breed 
 that you think will give best returns. You can start 
 with one hen and a setting of eggs, or you can buy 
 a number of young chicks that are a day or two old. 
 If your parents raise poultry you may get enough 
 from them for your start. Many poultrymen sell 
 and ship large numbers of young chicks. Keep a 
 very careful record of your project. 
 
 Record. 
 
 1. Expenditures. 
 
 a. Number and market value of chickens you start with. 
 
 b. Cost of necessary equipment. 
 
 c. Cost of feed. 
 
 d. Approximate cost of labor. 
 
 2. Receipts. 
 
 a. Number of eggs. 
 
 b. Value at market price. 
 
 c. Number of chicks raised. 
 
 d. Value of those sold. 
 
 e. Value of those kept for breeding purposes. 
 
 f. Value of those used at home. 
 
 3. Net profits. 
 
 4. Notes that will be of value for future reference. 
 
 If you live in a place where ducks or geese are 
 
POULTRY AND POULTRY PROJECTS 435 
 
 raised, you may be interested in starting a project 
 with these instead of with chickens. 
 
 A poultry club in the school will add to the value 
 of the projects. If this is undertaken, plans should 
 be made for an exhibit with a display of eggs and 
 chickens or other poultry. If practicable a poultry 
 house may be equipped on the school grounds and 
 poultry raised on a cooperative plan. Some of the 
 children may take the responsibility of caring for 
 the stock during vacation. 
 
CHAPTER XXVI 
 
 BIRDS 
 
 Material. Birds of the community, charts, pic- 
 tures, books and notebooks; when possible a pair of 
 field or opera glasses. 
 
 Study. You should become acquainted with every 
 bird in the vicinity of your home and school. 
 There is but one way to accomplish this and that is 
 to study birds at first hand, out-of-doors. Getting 
 acquainted means not only learning to identify birds, 
 but finding out everything you can about their lives 
 and habits. 
 
 If you are not familiar with many birds, you 
 cannot begin your observation at a better time than 
 late winter or very early spring. At this time the 
 number of different birds is not great and you can 
 easily learn to know them all before the spring mi- 
 gration brings in a large number of new species. 
 
 In order to make an intelligent study, you should 
 know the names of the different parts of a bird. Study 
 Fig. 83 until you are able to name all the parts when 
 you look at a live bird. When you go out on a field 
 trip, form the habit of taking a small notebook with 
 
 436 
 
BIRDS 437 
 
 you. Eeserve two pages for each bird. The fol- 
 lowing outline will be found helpful in keeping a 
 record : 
 
 1. Date: 
 
 2. Weather conditions: 
 
 3. Name: 
 
 4. Where is the bird: 
 
 5. Size: compare with wren, English sparrow, robin, crow. 
 
 6. Colors: 
 
 Head Crown Nape Bill 
 
 Back rump wings tail 
 
 Throat breast belly sides feet 
 
 7. Movements and habits. Note special characteristics of flight, 
 movements upon the ground, feeding habits and food, nesting habits, 
 time of nesting, material used, location of nest, share of the work 
 done by the male, by the female, care of the young. 
 
 Do not think that you must make a complete 
 record with your first observation, but add to it from 
 time to time as you become better acquainted with 
 the bird. One of the interesting things about bird 
 study is that no matter how long you may have 
 known a bird, you are constantly finding out new 
 facts about it. 
 
 Suggestions for field study. 1. Move slowly and 
 quietly. 2. If you have companions avoid talking to 
 them, or speak in a very low tone. 3. Study one 
 bird till you are sure of its colors; do not try to study 
 two or three at the same time. 4. Listen attentively 
 to the notes and songs so that in time you will be 
 able to identify birds by sound, as well as by sight. 
 
438 
 
 STUDIES IN SCIENCE 
 
 5. Learn to imitate as many of the notes as you can, 
 
 6. As far as possible keep the sun at your back in 
 order to see the colors more distinctly. 7. Plan to 
 make some studies in the early morning. An hour 
 before breakfast will often give better results than 
 two or three hours in the middle of the day. Next to 
 the early morning hours the late afternoon is the best 
 time to see birds. 
 
 'Crown 
 
 Fig. 83. Parts of a bird. 
 
 Bird Groups. Birds may be grouped into four 
 classes with reference to the period of time and the 
 season during which they remain in your locality. 
 
 1. Permanent residents are the species that are 
 found in the same region the year around. 
 
 2. Winter residents spend the winter in one local- 
 
BIRDS 439 
 
 ity and go farther north to nest and rear their 
 young. 
 
 3. Summer residents nest in one region but go 
 farther south to spend the winter. 
 
 4. Migratory visitors are birds that nest in the 
 far North, winter in the South, and stop at places 
 between for a few days or weeks during their spring 
 and fall journeys. You may discover for yourself the 
 many birds that belong to each of these different 
 groups. 
 
 Birds may also be grouped with reference to their 
 structure and appearance. Orinthologists have used 
 structural characteristics to classify birds into 
 orders, families, genera and species. 
 
 If you look in any good bird book you find besides 
 the common name, a scientific name. This is made up 
 of two words designating the genus and the species. 
 If, for example, you look at the description of a 
 flicker, you find in italics after the common name 
 colaptes auratus, which is the scientific name. Then 
 if you look farther you find that the flicker and all 
 other woodpeckers are placed in a group by them- 
 selves because they all have similar characteristics. 
 These constitiute the woodpecker family. A number 
 of families that have similar characteristics are put 
 together into a larger group called an order. 
 
 It is worth while finding out some of the family 
 
440 
 
 STUDIES IN SCIENCE 
 
 characteristics of the birds with which you become 
 acquainted. The parts of a bird that are commonly 
 considered in placing birds into family groups are 
 the bill and feet. The nesting and feeding habits and 
 the musical powers are in many cases also consid- 
 ered. 
 Descriptions. Select a number of good bird pic- 
 
 Fig. 84. Adaptations in the bills of birds. 
 
 tures. Compare the bills and feet to determine how 
 they differ. Put together those that have similar bills 
 and you will probably have some representative fam- 
 ily group. 
 Families. Describe the bills of song sparrows, 
 
BIRDS 
 
 441 
 
 the vesper sparrow, the goldfinch, the cardinal, the 
 rose-breasted grosbeak. 
 
 You find in every case a stout, rather short, con- 
 ical bill. These birds belong to the sparrow or 
 finch family. The hard stout bills are adapted for 
 
 Fig. 85. Adaptations in .the feet of birds. 
 
 - ' .!.>.'. l:i.~ 
 
 the crushing of seeds. These are the great seed 
 eaters among the birds. Many of them are also 
 noted for destroying insects, especially hard-shelled 
 insects. The rose-breasted grosbeak is one of the few 
 birds that is especially fond of the potato beetle. 
 
442 STUDIES IN SCIENCE 
 
 The bills of the members of the swallow family are 
 short and sharp and very wide at the base. These 
 birds spend most of their time on the wing catching 
 insects in the air. Their wide mouths are admirably 
 adapted to this kind of life. They have very long 
 wings and rather small, weak feet. When they alight 
 they choose a telephone wire or a small twig which 
 their small toes can grasp with ease. 
 
 If you look closely at pictures of wood warblers you 
 find the bills long, slender, and pointed; just the kind 
 to snap up insects from the leaves or bark of trees 
 and shrubs. The warblers are all small birds and 
 most of them are brightly colored. 
 
 The mockingbird family has long, rather slender, 
 slightly curved bills. Their bodies are slender and 
 their tails long. They are noted for their wonder- 
 ful musical power. Besides the true mockingbird, the 
 brown thrasher and catbird are the most common 
 members of this family. 
 
 Wrens are closely related to the mockingbirds, but 
 are placed in a family by themselves. Their bills are 
 similar to those of the mockingbirds. They, too, are 
 great musicians. 
 
 The creeper family is represented by but one species 
 here in America, That is the small brown bird that 
 you see creeping up the trunks of trees. The bill is 
 very slender, curved, and sharp pointed; With this 
 
BIRDS 443 
 
 needlelike bill the bird is able to get insect eggs and 
 tiny larvae from the smallest cracks and crevices of 
 the bark. 
 
 The thrush family includes two of our most familiar 
 birds, the robin and bluebird. The bills are long, 
 rather slender, and pointed. They are adapted for 
 eating either insects or fruit. All the thrushes except 
 the two common birds named have spotted breasts. 
 You may have observed that the young of both 
 robins and bluebirds have the characteristic spotted 
 thrush breast. The thrushes rank high among bird 
 musicians. 
 
 If you have examined the bills of the kingbird, pee 
 wee, or phoebe, you note that they are slightly curved 
 at the tip and wide at the base. These birds belong 
 to the fly catcher family. This family is noted for 
 catching insects on the wing. The bird usually sits on 
 a dead branch of a tree watching for insects. As one 
 flies by the bird darts out and skillfully catches it, 
 usually returning to the same perch again and again. 
 
 The blackbird family comprises a large number 
 of birds that differ considerably in their habits and 
 structure. Their bills are rather long, deep, and 
 pointed, adapted to picking up a variety of foods, 
 insects, seeds, and fruits. Some of them have very 
 little musical ability, while others are good songsters. 
 Besides all the different kinds of blackbirds, the 
 
444 STUDIES IN SCIENCE 
 
 meadow larks, orioles, and bobolinks belong to this 
 family. 
 
 All the families we have described thus far belong 
 to one great order called pass'eres or perching birds. 
 The arrangement of the toes is the same in all of 
 these birds; that is, three toes point forward and one 
 backward. 
 
 The members of the woodpecker family have strong, 
 slightly blunt, chisel-like bills which enable the birds 
 to peck holes in trees. The foot has two toes that 
 point forward and two that point backward. This 
 arrangement, with the sharp claws, adapts the foot to 
 tree climbing. The tail also aids in climbing. You 
 notice that it is short and that the feathers are pointed 
 and stiff. They help to prop the bird against the tree 
 while it is creeping upward. The tongue of the wood- 
 pecker is quite remarkable. It is very long and ends 
 in a hard tip with sharp barbs along the side. This 
 enables the bird to draw from their hiding places 
 the borers that feed under the bark of trees. 
 
 Hawks, eagles, and owls belong to an order known 
 as raptores or birds of prey. All of these birds have 
 strong hooked bills adapted for tearing flesh, very 
 strong feet and claws used for catching and carrying 
 prey, and long strong wings that enable them to fly 
 great distances. 
 
 Shore birds. If you live near water, lakes, ponds, 
 
BIRDS 445 
 
 or rivers you will have an opportunity to become ac- 
 quainted with shore birds and swimmers. 
 
 The shore birds are represented by the snipes, sand- 
 pipers and stilts. They have very long slender bills 
 which enable them to probe around in mud and sand 
 in search of insects and other choice morsels to eat. 
 The legs are long and are bare above the heel joint. 
 This makes it possible for them to wade in shallow 
 water without getting the feathers wet. The neck 
 also is long. 
 
 Ducks and geese are common representatives of the 
 family of swimmers. The bill is flat and broad with 
 a sieve along the edges of the mandibles. When the 
 birds get their mouths full of water, thin mud, 
 and particles of food, the sieve allows the water and 
 mud to flow out and leaves the food. The toes of 
 these birds are webbed so that they may be used as 
 paddles in swimming. The body is boat shaped, a 
 characteristic which also aids in swimming. Besides 
 ducks and geese, swans belong to this family. 
 
 Value of birds. Make a list of all the ways in which 
 birds are of value to us. It is no easy matter to esti- 
 mate accurately the good that birds do in the world. 
 They destroy countless numbers of insect pests. 
 It is probably fair to say that without the 
 aid of birds many of our farm crops would be part- 
 ially if not wholly destroyed every season. It is not 
 
446 STUDIES IN SCIENCE 
 
 farm crops alone that birds protect, but also gardens, 
 orchards, and forests. 
 
 You have only to watch a pair of wrens, thrashers, 
 robins or grosbeaks during the nesting season, work- 
 ing incessantly from dawn to dark collecting insects 
 from the yard and garden, to appreciate what great 
 benefactors they are. The seed-eating birds, the 
 finches and sparrows, aid us in devouring quantities 
 of weed seeds every year. The birds of prey, hawks, 
 and owls, are of great importance because of the 
 number of small rodents, mice, rats, gophers, ground 
 squirrels and the like, that they destroy. 
 
 Aside from their economic value birds are of impor- 
 tance because of their influence upon our lives. No 
 other phase of nature can bring more genuine pleasure 
 than bird study. To know birds, to appreciate their 
 beauty of song and color, to love them for themselves 
 and for their interesting ways and habits, will bring 
 you joy not only now, but all the days of your life. 
 
 Enemies of birds. Make a list of the enemies of 
 birds. 
 
 1. Destruction of nesting places. The clearing of 
 woodlands is progressing to such an extent that in 
 many localities the birds are disappearing because 
 they no longer have places in which to build their 
 nests and rear their young. The breaking up of 
 prairie lands and the draining of swamps in the 
 
BIRDS 447 
 
 Middle West have already driven large numbers of 
 birds from that region. 
 
 2. Destruction of drinking and bathing places by 
 the draining of ponds, open ditches and small streams. 
 
 3. Cats. Professor Forbush, of Massachusetts, esti- 
 mates that a single cat is responsible for the death of 
 about fifty song birds a year. 
 
 4. The robbing of nests by boys who have a mania 
 for collecting eggs. 
 
 5. The destruction of birds for millinery purposes. 
 
 6. English sparrows. These foreign birds drive 
 away from our homes many of our most beneficial and 
 beautiful song birds. 
 
 7. Red squirrels. These are becoming so numerous 
 in some towns that they are destroying scores of 
 bird nests every season. 
 
 Protection and care. You can do much, not only to 
 protect birds from their enemies, but to actually in- 
 crease the numbers in your community. One of the 
 first things is to provide nesting places. Every coun- 
 try community should have a bird refuge in connec- 
 tion with each farm. A few shrubs or low trees along 
 the highway or in clumps in fence corners will keep 
 in the neighborhood scores of useful birds that will 
 pay for their nesting site by destroying myriads of 
 noxious insects. 
 
 Boxes or bird houses may be provided for birds that 
 
448 STUDIES IN SCIENCE 
 
 nest in cavities. Use old weather beaten lumber, or, 
 if new material is used, paint the houses a dull gray or 
 brown. For wrens and chickadees make the hole for 
 the entrance about one inch in diameter. This will 
 prevent English sparrows from entering. Larger birds 
 that nest in boxes are the bluebird, tree swallow, 
 purple martin, nuthatch, flicker, titmouse, phoebe, and 
 screech owl. 
 
 Tin cans, old tea and coffee pots, and gourds may 
 be used instead of boxes. You can attract some birds 
 by furnishing building material for them. Place 
 twine or yarn on bushes for orioles, a pan of mud for 
 robins, and hairs, dry grass, rootlets and threads for 
 other birds. Birds need water both for drinking and 
 bathing. Pretty bird basins or baths may be pur- 
 chased, but you can easily arrange your own at small 
 cost. 
 
 A little basin of cement with sloping bottom and 
 fringed with rocks and ferns may be placed in a 
 hollow in the back yard. Common granite iron pans 
 from two to four inches deep may be used. Place 
 a layer of clean sand or fine gravel in the bottom or a 
 flat stone for small birds to stand upon. If the pan is 
 set upon a block or stump a few feet from the ground, 
 cats are not so likely to disturb the birds while in the 
 bath. 
 
 Help get rid of. all the stray cats in the neighbor- 
 
BIRDS 
 
 449 
 
 Lood. If you have cats of your own, feed them with 
 la meat diet so they will not attack the birds because 
 of hunger. Do all you can to train them to leave 
 birds alone, or keep them indoors during the nesting 
 [season. 
 
 Birds may be kept near your home all winter by 
 [supplying food for them. Nuthatches, chickadees, 
 hairy and downy woodpeckers, brown creepers as well 
 as jays, will feed upon beef suet tied firmly in the 
 crotch of a tree or suspended from a branch. Meat 
 rinds or shank bones may also be used. Native 
 sparrows, juncoes, gold finches and other seed eating 
 birds may be attracted by a feeding tray made out of 
 boards and fastened to some support four or five feet 
 high. This tray should be kept supplied with chaff 
 from the haymow, sunflower seeds, millet, and other 
 seeds. During the early spring days when insect food 
 is scarce, robins and bluebirds enjoy crumbs from the 
 table. 
 
 Consult the Shrub List, page 460, to find what 
 shrubs have berries that attract birds both in summer 
 and winter. Besides the shrubs, the following trees 
 furnish attractive food for birds: white and red mul- 
 berry, mountain ash, hawthornes, June berry, wild 
 cherry and flowering dogwood. 
 
 Do not wear birds on your hat, even if the millin- 
 er insists that they are made of chicken feathers. The 
 
450 STUDIES IN SCIENCE 
 
 principle remains the same whether they are real or 
 artificial. 
 
 With the help of your teacher, look up the laws of 
 your own state for the protection of birds and do all 
 you can to see that they are enforced. 
 
 \ 
 
 BIRD LISTS 
 
 1. Birds that feed upon insects injurious to field crops: Meadow 
 lark, bobwhite, dickcissel, indigo bunting, killdeer, Maryland yel- 
 low throat, redwing blackbird, bobolink, brown thrasher, bronze 
 grackle, cowbird, horned lark, song sparrow, field sparrow, other 
 native sparrows, plover. 
 
 2. Birds that feed upon insects injurious to garden and fruit 
 crops: House wren, catbird, rose-breasted grosbeak, robin, blue- 
 bird, oriole, chickadee, downy and hairy woodpecker, chipping 
 sparrow, yellow warbler, nuthatch, brown creeper, mocking-bird. 
 
 3. Birds that destroy flying insects about the home: Chimney 
 swift, barn swallow, tree swallow, purple martin, kingbird, night 
 hawk, phoebe. 
 
 4. Birds that are especially beneficial to forest and shade trees: 
 All the warblers, scarlet tanager, summer tanager, the cuckoo, vireo, 
 thrush, pewee, titmouse, whip-poor-will, chuck-wilFs-widow, chewink, 
 white-eyed vireo, all woodpeckers, nuthatch. 
 
 ?. Birds that feed upon weed seeds: Goldfinch, white-throated 
 sparrow, white-crowned sparrow, tree sparrow, junco, mourning 
 dove. 
 
 6. Birds that destroy mice, ground squirrels and injurious 
 rodents: Red-tailed hawk, red -shouldered hawk, marsh hawk, rough- 
 legged hawk, screech owl, short-eared owl, barred owl, snowy owl, 
 barn owl, horned owl. 
 
CHAPTER XXVII 
 
 LANDSCAPE GAEDENING 
 
 If you look at any well arranged home or school 
 grounds you find five distinct kinds of plants used 
 to make them attractive. First there is grass in the 
 lawn or open stretches, then there are trees, shrubs, 
 vines and flowering plants. The artistic arrange- 
 ment of these different groups of plants in relation 
 to each other and to buildings, walls, and walks or 
 drives constitutes what we call landscape gardening. 
 The men and women who make a business of plan- 
 ning and planting such grounds are known as land 
 scape gardeners or landscape architects. 
 
 While you can not attempt to do the work of the 
 landscape gardener, you can learn some of the under- 
 lying principles, and, in cooperation with your 
 parents and teachers, undertake a few projects to 
 make your home and school grounds more beautiful. 
 This need not interfere with your vegetable projects. 
 You may very well undertake the care of a vegetable 
 plot and a home improvement plan at the same time. 
 
 451 
 
452 STUDIES IN SCIENCE 
 
 THE LAWK 
 
 In any plan for improvement of grounds the lawn 
 should receive first consideration. It is the canvas of 
 the landscape picture "upon which the artist paints 
 with tree and bush and flower as the painter does 
 upon his canvas with brush and pigment.'' 
 
 In all the states north of latitude 38 to 40, Ken- 
 tucky blue-grass is the favorite lawn grass. For spe- 
 cial conditions, such as very shady spots, dry sunny 
 slopes, or for low wet lands, other grasses are 
 mixed with this. In fact, other seeds are frequently 
 mixed with blue-grass in starting an ordinary lawn. 
 Some people use other grasses and some use white 
 clover. Barron in his book entitled "Lawns" sug- 
 gests the following mixture for any lawn that has 
 a clay soil: 
 
 Kentucky blue-grass 50% 
 
 English rye 20% 
 
 Fancy red top 
 
 The rye grows rapidly and covers the surface with 
 green in a short time. After a few years if the blue- 
 grass does well* it takes complete possession of the 
 space. In the South, Bermuda is the chief lawn 
 grass. 
 
 Other mixtures suggested by the same writer are: 
 
LANDSCAPE GARDENING 453 
 
 For terraces or slopes 
 
 Creeping bent or Rhode Island bent 40% 
 
 Crested dog's tail 25% 
 
 Canada blue-grass 25% 
 
 Kentucky blue-grass 10% 
 
 For shaded places 
 
 Kentucky blue-grass 40% 
 
 Wood meadow grass 40% 
 
 Various leaved fescue 10% 
 
 Crested dog's tail ; 10% 
 
 Some localities are so shady that it is impossible 
 to get a stand of grass. In that case other plants 
 may be used to cover the ground and give a pleas- 
 ing effect. Myrtle is excellent for this purpose. So 
 is common ground ivy. 
 
 Blue-grass. Material. A grass plot in home or 
 school yard; a small piece of sod taken from some 
 corner where it will not be missed; specimens, of seed 
 heads; seeds. 
 
 The suggested topics for blue-grass may be used 
 for any other lawn grass. 
 
 Problem. What are the characteristics that make 
 blue-grass a good lawn grass? Note the habit of 
 growth of the grass. Try to separate the individual 
 plants from each other. How close together are they? 
 Try to pull up one grass plant. What happens ? 
 Why does it break off instead of coming up by the 
 roots? What direction do the leaves take in their 
 
454 STUDIES IN SCIENCE 
 
 growth! How are they fastened to the stem? Eemove 
 a leaf and examine it. Compare the lengths of sheath 
 and blade. Determine whether the blade is flat or 
 folded toward the mid-rib. Examine a number before 
 you decide. 
 
 Rootstock and roots. Examine the piece of sod. 
 How many distinct structures do you find penetrating 
 the ground! Describe each. Wash all the soil out 
 of a small piece in order to see the parts clearly. 
 What is the greatest number of rootstocks that you 
 find growing from a single plant! What is the direc- 
 tion of growth! What is there at the free end! Of 
 what advantage to the plant is the rootstock! 
 
 Seeds. Study the seed-head. How tall is it! How 
 does it branch! Where are the seeds! Eemove all 
 the seeds from one head and measure. Describe the 
 seeds as to size and color. Compare with those of 
 other grasses. Make a collection of all the different 
 heads of grass seeds available and mount them on a 
 stiff cardboard. 
 
 Experiment. Effect of depth of planting on germ- 
 ination and growth. In a box of soil plant several 
 rows of seeds at depths varying from a mere cover- 
 ing to two inches. Determine which germinate and 
 grow best. If possible make the experiment out-of- 
 doors also. What is the price of blue-grass seed! 
 How large a space will a pound sow! How many 
 
LANDSCAPE GARDENING 455 
 
 pounds in one bushel? How much will it cost to sow 
 an acre? 
 
 The home lawn. Examine your home lawn. ' 
 Which way does it slope? Has it any terraces? Is 
 it in good condition? If not, what can you do to im- 
 prove it? Look for dead leaves and other trash, bare 
 spots, weed patches, uneven spots. What rules are 
 followed regarding mowing? 
 
 Discussion. From your observation you find that 
 blue-grass grows in a very crowded condition. This 
 is one of the characteristics that makes it an excel- 
 lent lawn grass. 
 
 The underground parts are quite as important. 
 You found the great mass of fine fibrous roots that 
 help to make a firm turf or sod and the thicker root- 
 stock which is an underground stem. If you exam- 
 ined it closely you found that it has nodes with scale 
 leaves, and a growing bud at the end. The rootstock 
 grows horizontally and enables the grass to spread 
 evenly over the ground. It is a great advantage to 
 the plants during severely cold or dry weather. All 
 the parts above ground may be killed, but the root- 
 stock with its buds remains uninjured and sends up 
 new plants as soon as the proper conditions of 
 moisture and warmth are restored. 
 
 Blue-grass sends up its flowering head in the early 
 summer, and the seeds ripen within a few weeks. 
 
456 STUDIES IN SCIENCE 
 
 This kind of a head with many branches is called a 
 panicle. 
 
 * Starting a lawn. If you wish to start a new lawn, 
 the first requirement is a deep seed-bed of rich 
 mellow soil. Level the surface, leaving a slight slope 
 from the house to the road or street if desired. You 
 may start a lawn in two ways, by the use of sods or 
 by seeds. The latter is less expensive and is the 
 one commonly used. The seed may be sown in the 
 fall any time before the ground freezes, or in the 
 spring. Spring seeding should be done as early as 
 possible so that the plants will get a fair start before 
 dry, hot weather. 
 
 Choose a day to sow when the wind is not blowing 
 briskly, scatter the seeds evenly and thickly, about 
 one pound to 100 square yards. Rake the soil lightly. 
 If possible run a roller over it. If it does well it will 
 be ready to mow in six weeks or two months. 
 
 Caring for the lawn. If you find bare spots in 
 your lawn rake out all the trash, put in some fresh 
 soil, then seed thickly. If there are weeds dig them 
 out and sow grass seeds in their place. If the lawn is 
 uneven the use of a heavy roller will greatly improve 
 it. Eolling at least once in the spring is good for 
 any lawn whether uneven or not. 
 
 The lawn should be mowed often enough to keep a 
 smooth velvety grass covering. In dry weather care 
 
LANDSCAPE GARDENING 457 
 
 should be taken not to mow too close to the ground 
 as there is danger of injuring the roots. In fact, it 
 is best to have the mower set high at all times. 
 Evening is a better time for mowing than morning. 
 Do you see why? The grass has the cool night in 
 which to recover from the shock of the cutting. In 
 dry weather it is best to allow the clippings to lie 
 instead of catching them or raking them up. 
 
 If you water your lawn you will find that a 
 thorough drenching once or twice a week will keep 
 it in better condition than a light sprinkle every 
 day. 
 
 Home projects. No home project that you can 
 undertake will give you more real pleasure and satis- 
 faction than caring for the lawn. You will have 
 some enemies to contend with. The most common 
 and the hardest to combat are weeds. Eemoving 
 them root and all is the surest way to get rid of them. 
 Do not allow a single one to go to seed. (See Weeds, 
 p. 77.) 
 
 1. SHKUBS 
 
 Material. Shrubs of the neighborhood, park, 
 nurseries, and woodlands, catalog containing price 
 lists. 
 
 Study. Make a list of all the shrubs in your district 
 whose names you know. Choose several for special 
 
458 STUDIES IN SCIENCE 
 
 study. What is their habit of growth? How do they 
 differ from trees? What is the height and color 
 of the stem? Are the twigs stiff and erect or droop- 
 ing? Examine the twigs for buds and scars. Which 
 shrubs have retained their fruit or berries over 
 winter? Have you seen any birds feeding upon 
 them? Keep a simple shrub calendar showing dates 
 of the opening of leaf and flower buds. How are 
 shrubs usually propagated? (See Cuttings, p. 263.) 
 
 Make a list of native shrubs in nearby woods. 
 How many of these do you find on home or school 
 grounds ? 
 
 Notice the homes in your district and decide which 
 ones have the shrubs arranged most artistically. 
 How many of the rules for shrub planting do you 
 know ? 
 
 Discussion. Shrubs, more than any other plants, 
 may be used to give a beautiful, natural setting to a 
 home. They differ from trees in that they send up 
 a number of stems from the root instead of one main 
 trunk. They never grow as tall as trees and many of 
 the most beautiful ones have drooping branches. In 
 cool climates they have the same habit as trees in 
 preparing for the winter season; that is, they start 
 their buds in the latter part of the summer, cease their 
 work, and the deciduous ones drop their leaves. 
 
 Projects. If you are planning to set out shrubs 
 
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460 
 
 STUDIES IN SCIENCE 
 
 on home or school grounds you must know not only 
 the best shrubs to use, but how and where to place 
 them. To begin with you should observe the follow- 
 ing general rules: 1. Leave an open lawn with the 
 shrubbery grouped at the sides or near the build- 
 ings. 2. Plant to give mass effect; do not scatter 
 the shrubs. 3. Avoid straight lines except in the 
 making of hedges. 4. Put together colors that will 
 harmonize, or plan for a succession of flowers. 
 
 With the consent of your parents draw up a plan 
 for the planting of your home grounds. The work 
 need not be completed in one year. Start it now and 
 continue year after year till it is finished. It .is very 
 important to have a well arranged plan before you 
 begin. 
 
 SHRUB TABLE 
 
 The date of flowering is given for regions in about 40 north 
 latitude. N. after a name indicates that the shrub is native to this 
 country. Shrubs that are starred are especially attractive to birds. 
 
 Name 
 
 Date of 
 flowering 
 
 Color of 
 flower 
 
 Color of 
 fruit 
 
 Low from 2 to 4 ft. 
 * Japanese barberry 
 
 June 
 
 Pale yellow 
 
 Scarlet 
 
 Berberis Thunbergii 
 Indian currant N 
 
 June 
 
 White 
 
 Red 
 
 Symphoricarpus vulgaris 
 Sweet scented sumac N 
 Rhus aromatica 
 Dwarf spirea 
 Spirea Japonica 
 
 July 
 March-April 
 
 Yellow 
 White 
 
 Dark red 
 
LANDSCAPE GARDENING 
 
 461 
 
 Name 
 
 Date of 
 flowering 
 
 Color of 
 flower 
 
 Color of 
 fruit 
 
 Early spirea 
 
 March-April 
 
 White 
 
 
 Spirea arguta 
 Low hydrangea N 
 
 July 
 
 White 
 
 
 Hydrangea arborescens 
 New Jersey tea N 
 
 June 
 
 White 
 
 Black 
 
 Ceanothus Americanus 
 Spice bush N 
 
 May 
 
 Dark purple 
 
 
 Calycanthus floridus 
 Low deutzia . . . 
 
 June 
 
 White 
 
 
 Deutzia gracilis 
 'Honeysuckle 
 
 May 
 
 White 
 
 Red 
 
 Diervilla lonicera 
 
 July-August 
 
 Greenish 
 
 Red 
 
 Rhus copalina 
 
 Medium from 5 to 7 ft. 
 *High bush cranberry N. . . . 
 Viburnum opulus 
 *Arrowwood N 
 
 May-June 
 June 
 
 White 
 White 
 
 Bright red 
 
 Viburnum acerfolium 
 Golden bell 
 Forsythia intermedia 
 *Honeysuckle 
 
 March-April 
 May-June 
 
 Yellow 
 White-yellow 
 
 
 Lonicera Morrowii 
 Spirea 
 
 May 
 
 White 
 
 
 Spirea Van Houttei 
 Snow berry N 
 
 June-July 
 
 Pink 
 
 White 
 
 Symphoricarpus racemosus . 
 White kerria 
 
 Mav 
 
 White 
 
 Rlarfr 
 
 Rhodotypos kerriodes 
 Weigelia 
 
 Mav-June 
 
 Rose 
 
 
 Weigelia rosea 
 *Flo\vering currant N 
 Ribes aureum 
 Dogwood N 
 
 April-May 
 May-June 
 
 Yellow 
 White 
 
 Black 
 
 Whitish 
 
 Cornus stolonifera 
 
 
 
 
462 
 
 .STUDIES IN SCIENCE 
 
 Name 
 
 Date of 
 flowering 
 
 Color of 
 flower 
 
 Color of 
 fruit 
 
 Hydrangea * 
 
 July-August 
 
 White-rose 
 
 Bronze 
 
 Paniculata grandiflora 
 False Indigo N. , ... 
 
 May-June 
 
 Blue 
 
 
 Amorpho fruticosa 
 Privet 
 
 June 
 
 White 
 
 Black 
 
 Ligustum amurense 
 Privet 
 
 June 
 
 White 
 
 Blue 
 
 Ligustum regels 
 
 High from 7 to 12 ft 
 *Elder N 
 
 July- August 
 
 White 
 
 Black 
 
 Sambucus canadensis 
 *Honeysuckle 
 
 May-June 
 
 Pink 
 
 Red 
 
 Lonicera tartaria 
 *Sumac N . 
 
 June-Julv 
 
 Red 
 
 Red 
 
 Rhus typhina 
 Button bush N , . .. 
 
 May 
 
 White 
 
 
 : Cephalanthus occidental is 
 Japan quince 
 
 April-Mav 
 
 Red 
 
 
 Pyrus japonica 
 Mock orange, Svringa 
 
 June 
 
 White 
 
 
 Philadelphus coronarius 
 Lilac 
 
 April-Mav 
 
 Lavender 
 
 
 Syrihga vulgaris 
 Sweetbrier rose N 
 
 June 
 
 Pink 
 
 Red 
 
 Rosa rubiginosa 
 Prairie rose N 
 
 June 
 
 Pink 
 
 
 Rosa setigera 
 
 
 
 ... ? , ... , 
 
 rf fcr.,.f.< 
 
 'jfco.'l^ 
 
 You have such. a large number of shrubs from which 
 to choose that you may find it difficult to decide which 
 ones to use. As far as possible, select those that are 
 native to your locality. While you may get some of 
 them directly from the woods, they usually give better 
 
LANDSCAPE GARDENING 463 
 
 results if obtained from a nursery where they have 
 been grown under conditions similar to those of your 
 home grounds. From your study of cuttings you 
 know that if you are willing to wait a year or two for 
 results, you may start many of you own shrubs. 
 
 Border planting. In order to carry out the sug- 
 gested rules, plan for an irregular border with curved 
 lines along the sides of the yard. Do not make the 
 border wide enough to encroach far upon the open 
 lawn. Place the plants close enough together so that, 
 after a few years, the individuals will be obscured in 
 the mass effect. Put the tall shrubs in the back- 
 ground with the medium and low in front. Consult 
 the Shrub Table, page 460. If the yard is narrow, it is 
 better not to use very tall plants but arrange group- 
 ings of the medium and low. A clump in the corner 
 running back to a few near the fence or boundary at 
 the middle of the yard, with another clump extend- 
 ing toward the building, gives a very pretty effect 
 for a small yard. 
 
 SUGGESTED GROUPINGS FOB BORDERS 
 (1, 2, and 3 are suitable for large yards only.) 
 
 1. Sumac, typhina, Dogwood, and Indian currant 
 
 2. Elder and Forsythia 
 
 3. Japan quince, honeysuckle, and white kerria 
 
 4. High bush cranberry, snowberry, and Japanese barberry 
 
 5. Spirea Van Houttei and dwarf spirea 
 
 6. Spirea Van Houttei and Japanese barberry 
 
464 STUDIES IN SCIENCE 
 
 7. In clumps by themselves: 
 Hydrangea 
 Indian currant 
 Honeysuckle 
 Snowberry 
 Sumac, Copalina 
 Spice bush 
 
 Foundation planting. The chief purpose in plac- 
 ing shrubs and other plants close to the house is to 
 unite the building and the grounds so that they will 
 seem to belong together. The plan of the house 
 should be studied before you can decide where to 
 place the plants. There is always danger of using 
 too many shrubs. Mass them in the angles of 
 porches, bay windows, and steps. Allow the clumps 
 at the corners to extend a short distance along 
 walks or form irregular screens to obscure outbuild- 
 ings. Plan for some breaks so that the foundation of 
 the house will here and there be directly united with 
 the grass of the lawn. Place the highest shrubs near 
 the buildings with the lower groups next to the lawn, 
 Choose those whose branches droop lightly and grace- 
 fully over the grass. 
 
 SUGGESTED GROUPS FOR FOUNDATION 
 
 1. Spirea Van Houttei and Japanese barberry 
 
 2. Honeysuckle, Morrowii, and Deutzia gracilis 
 
 3. Forsythia intermedia and low hydrangea 
 
 4. Indian currant and Deutzia gracilis 
 
 5. White kerria and dwarf spirea 
 
LANDSCAPE GARDENING 465 
 
 Buying and planting. If you buy shrubs from a 
 nursery, you will find that the younger, smaller 
 plants are less expensive and give quite as satisfac- 
 tory results as larger ones. 
 
 In colder portions of the country, shrubs may be 
 set out either in the spring or fall. If the soil is 
 moist, they will do well in the fall. Spring planting 
 should be done as early as the ground can be worked. 
 It should always be done before the shrubs have put 
 out their leaves. 
 
 Eules to follow in planting: 
 
 1. After the plants are removed from the nursery 
 grounds, keep the roots well covered and moist till 
 you are ready to set them out. 
 
 2. Dig a round hole, large enough so that the roots 
 may be spread out, and deep enough so that the plant 
 may be set a little farther below the surface than 
 it was before being removed from the ground. 
 
 3. Be sure that the soil in the lower part of the 
 hole is rich and mellow. It is sometimes a good plan 
 to put a few spadefuls of rich soil in the bottom of 
 the hole. 
 
 4. Place the plant in the hole with roots spread 
 out. Put in a few spadefuls of earth, then firm it well 
 about the roots. This is usually done by trampling 
 with the feet. Put in some more earth and firm again. 
 Continue this until the hole is filled. The last three 
 
466 STUDIES IN SCIENCE 
 
 or four inches of earth need not be firmed. The loose 
 soil will help to conserve the moisture. 
 
 5. If the soil is dry it is a good plan to pour a pail 
 of water into the hole; at least it should be 
 thoroughly watered. If the soil is moist, watering is 
 not necessary. 
 
 Care of shrubs. Stir the soil to a depth of several 
 inches two or three times during the first two years. 
 After that once a year is sufficient. Shrubs require 
 little care. They should be allowed to grow naturally, 
 hence they need little pruning. Severe pruning in 
 the spring should be avoided. If, after a number of 
 years, the shrubs are too thick or full, it is better to 
 remove one or two bodily from the clump or cut out 
 the old large branches so you will not spoil the 
 shape of the shrubs. For a number of years it is 
 necessary only to see that all dead wood is removed. 
 
 Hedges. While the irregular border gives an op- 
 portunity for greater variety and more artistic 
 arrangement of plants, yet some people like to have 
 their grounds enclosed with a shrub hedge or fence. 
 Much work is required to keep such a hedge in good 
 condition, for after a few years it must be trimmed 
 at least once each season, usually two or three 
 times. A hedge may be used between the back yard 
 and vegetable garden, even if the border planting 
 is used in front. 
 
LANDSCAPE GARDENING 467 
 
 Plants for hedges. Deciduous: Japanese bar- 
 berry, Berberis Thunbergii, common barberry, Amoor 
 Eiver privet, California privet. This last winter kills 
 in northern and north central states. 
 
 Evergeen: Arbor vitae, Norway spruce. 
 
 Shrubs and birds. While you are making your 
 home and school surroundings more beautiful by the 
 use of shrubs and vines, you may. at the same time 
 provide a home for wild birds. Many birds love a 
 shrub thicket in which to nest. By choosing shrubs 
 that produce edible berries you may have birds com- 
 ing to feed, not only during the summer, but far into 
 the winter months. In the Shrub Table, page 460, the 
 ones that are starred are especially attractive to birds. 
 
 2. VINES 
 
 Vines, as well as shrubs, may be used to add 
 beauty to the home and its surroundings. Make a 
 study of the vines that you know. Determine how they 
 climb. How many different methods of climbing do 
 you find? Of what advantage to plants is the climb- 
 ing habit? Classify vines as to their length of life. 
 
 If you look closely at vines you find that some 
 climb by twining their stems around supports. The 
 morning-glory is a good example of a twiner. Others 
 climb by little tendrils or roots which hold fast to 
 the support, as the sweet-pea or Boston Ivy. Some 
 
468 STUDIES IN SCIENCE 
 
 plants with tendrils also twine, as the wild grape. 
 There are a few climbers, chiefly roses, that simply 
 scramble over the supports. 
 
 Some vines are annuals, some perenials. Peren- 
 nials are, for most purposes, more satisfactory than 
 annuals. Annuals are grown largely for their 
 flowers, while perennials are used for permanent 
 screens or to decorate pillars, porches, and even the 
 walls of buildings. 
 
 Vines may be used to advantage on any home or 
 school grounds. You may use them to cover 
 unsightly buildings, as old woodsheds, coal houses, 
 etc. They may trail over the back fence and make a 
 background for a flower border. They add both 
 beauty and comfort when used as porch screens. In 
 a large yard a rose arbor repays in pleasure all 
 the work and effort required to make it a success. 
 
 Some of the most satisfactory perennials are: 
 
 Virginia Creeper or Woodbine, Ampelopsis quinquefolia. 
 
 Japanese, or Trumpet creeper, Teconia radicans. 
 
 Bitter sweet, Celastrus scadens. 
 
 Wild grape, Vitis bicolor. 
 
 Wild clematis, Clematis Virginiana and paniculata. 
 
 Wistaria, Wistaria siensis. 
 
 Illinois Rose, Rosa setigera. 
 
 Dutchman's pipe, Aristolochia macrophylla. 
 
 Green brier, Smilax rotundifolia. 
 
 For the South: 
 
 Yellow Jessamine, Geisemium sempervirens. 
 Malayan Jessamine, Trachelospermum Jasminoides. 
 
LANDSCAPE GARDENING 469 
 
 Climbing Asparagus, Asparagus plumosus. 
 
 Kudzu vine, Pueraria Thunbergiana. 
 
 Cherokee rose. 
 
 Muscadine, Vitis rotundifolia. 
 
 Annuals: Sweet pea, tall nasturtium, cypress vine, morning-glory, 
 moonflower, cobea, canary bird vine, Balsam pear, wild cucumber, 
 scarlet runner, velvet or banana bean. 
 
 Very pleasing effects are gained by planting a 
 few annuals with the perennials, and allowing them to 
 clamber up the woody stems of the hardy plants. 
 
 In planting and caring for perennial vines follow 
 rules suggested for shrubs. 
 
 In your treatment of annuals see Planting Table, 
 p. 474. 
 
 3. PERENNIAL FLOWERS 
 
 Look in catalogs for lists of hardy perennials and 
 decide which ones you would like to grow. Nothing 
 can give you more pleasure than a border of peren- 
 nials in your flower garden. Some of them may be 
 started at once from seeds in the garden border, 
 although they probably will not blossom the first 
 year. An easy way to start perennials is to arrange 
 a bed of rich mellow soil in a sheltered place in the 
 garden, and sow the seeds, placing different species 
 in rows by themselves. When the seedlings come up, 
 thin them until they stand about three inches apart. 
 When they are three or four inches high, transplant 
 them to their permanent places in the border. If you 
 
470 STUDIES IN SCIENCE 
 
 have a hotbed or green house, you may start them 
 very early and get quicker results. You may also 
 sow the seeds out-of-doors in the latter part of sum- 
 mer, treating the seedlings as suggested above. In 
 the fall cover them with a layer of leaves or straw. 
 In the spring they will be ready to transplant to 
 their permanent places. 
 
 Perennials may be propagated by roots or under- 
 ground stems, as well as by seeds. The underground 
 parts are dug up and divided, and the roots set 
 out either in the spring or fall. People who have 
 perennials several years old are willing to divide 
 their plants in this way. In some cases it is .an ad- 
 vantage to the plants to dig them up and separate 
 the accumulation of underground parts. 
 
 To make an artistic perennial border you must 
 know the height of the plants and the color of the 
 flowers. Group the plants to give a mass effect. Place 
 tall ones in the rear, with clumps of medium and 
 low in front. Mass species of the same color 
 together. Use low plants for edgings. 
 
 LIST OF PERENNIALS 
 
 Tall, from 5 to 8 feet: Golden glow, Blackeyed Susan (Rudbeckia), 
 Sunflower, Helianthus multiflorus, Rudbeckia purpurea, Rudbeckia 
 maximia, Golden-rod, Bocconia, Hollyhock. 
 
 Medium, from 18 inches to 4 feet: Columbine, Bleeding heart, 
 Peonies, Hardy Gaillardia, Japan Iris, Oriental Poppy, Phlox, Lark- 
 spur, Cardinal Flower, Coreopsis, Sweet William, Shasta Daisy, 
 Crimson-eye Mallow, Pyrethum, Hardy Chrysanthemum. 
 
LANDSCAPE GARDENING 471 
 
 Low, 6 to 12 inches: Hardy candy tuft, Forget-me-not, Orna- 
 mental grasses, Low iris, Lily of the Valley, Meadow rue, Shoot- 
 ing Star. 
 
 4. ANNUAL FLOWEKS 
 
 Material. Seeds, catalogs. 
 
 First look in your seed catalog for the plants that 
 you know, then for others that you think you would 
 like to grow. Consult table for colors. Do not choose 
 many unless you are going to work a large plot of 
 ground. If you are planning to sell flowers, choose 
 those that are most likely to be in demand and that 
 continue to blossom for some time. Sweet peas, pan- 
 sies, asters, gladiolus, dahlia, tube roses all sell well. 
 
 If you are raising your flowers for home use, 
 choose the ones that the family like best. It is, 
 however, always worth while to try at least one 
 new species. 
 
 SUGGESTED GROUPS FOB PROJECTS 
 (Those that are starred are excellent for cut flowers.) 
 
 Name Height Color 
 
 1. Sweet alyssum 9 in. White 
 
 *Cornflower or bachelor 
 
 button 18 in. Blue 
 
 2. Dwarf Nasturtium 12 in. Yellow and Orange 
 
 *Gaillardia 15 to 18 in. Yellow, Orange, Dark Red 
 
 3. Verbena 6 to 9 in. Mixed colors 
 
 *China asters.. ..18 to 24 in. Mixed colors 
 
472 STUDIES IN SCIENCE 
 
 (Those that are starred are excellent for cut flowers.) 
 
 4. *California poppy... 
 
 12 in. 
 
 Yellow 
 
 *Calendula 
 
 15 in. 
 
 Yellow 
 
 5. Pansies 
 
 6 in. 
 
 
 *Larkspur 
 
 15 in. 
 
 Blue 
 
 6. Portulaca 
 
 6 in. 
 
 Mixed colors 
 
 *Sweet scabious 
 
 15 in. 
 
 Mixed colors 
 
 7. Dwarf marigold 
 
 9 in. 
 
 Shades of yellow 
 
 Calliopsis 
 
 15 in. 
 
 Shades of yellow 
 
 8. Dwarf coxcomb 
 
 ... 9 to 12 in. 
 
 Purple-red 
 
 Tall coxcomb 
 
 24 te 30 in. 
 
 Purple-red 
 
 9. Ageratum 
 
 ... 6 to 9 in. 
 
 Blue 
 
 Corn flower 
 
 18 im. 
 
 Blue 
 
 10. Sweet alyssum 
 
 9 in. 
 
 White 
 
 Browallia 
 
 15 in. 
 
 Blue 
 
 
 The following are prettier if planted in beds by themselves: 
 Zinnia, *Dahlia, *Cosmos, Gladiolus, Poppies, Balsam, Pinks, Pe- 
 tunia, Salvia. 
 
 If you are going to succeed with your flower 
 projects, you must know something of the habits 
 of the plants you are to grow, as well as when, where, 
 and how to plant them. Some seeds are hardy 
 enough to grow in cool soil and the plants are able 
 to stand a low temperature, even a slight frost, with- 
 out injury. Others must not be planted until the 
 soil is warm and all danger of frost is past. Still 
 others in northern states must be started indoors and 
 transplanted when the weather is warm. 
 
LANDSCAPE GARDENING 
 
 473 
 
 PLANTING TABLE ANNUAL FLOWERS 
 
 The numbers indicate height. No. 1 from 6 to 9 inches, No. 2, 10 
 to 18 inches, No. 3, 19 to 24 inches, No. 4, 27 to 30 or more inches. 
 
 Name Col 
 
 Date to Plant 
 
 cu Distance Inches 
 
 S 1 " In Row 
 Q Of Rows 
 
 1 Ageratum, blue, white... 
 
 Indoors, Mr. 25 to Apr. 5 
 Garden, May 10 to 15. 
 April 1 to 15 
 
 K 
 
 % 
 
 % 
 
 % 
 
 \ 
 
 I 
 I 
 I 
 
 \ 
 V* 
 
 % 
 % 
 
 8 
 
 % 
 
 l 
 
 % 
 % 
 % 
 
 i 
 i 
 
 it 
 
 Vs 
 
 % 
 
 H 
 
 % 
 
 % 
 % 
 1 
 
 % 
 
 9 
 9(3) 
 9 
 
 12 
 12 
 12 
 9 
 9 
 12 
 9 
 9 
 12 
 
 9 
 9 
 18 
 
 12 
 9 
 Hills 
 
 12 
 to 
 15 
 12 
 2to4 
 9 
 
 9 
 
 12 
 
 12 
 9 
 
 6 
 
 12 
 & 
 
 e 
 
 6to9 
 12 
 12 
 
 1 
 12 
 
 12 
 9 
 12 
 
 15 
 18 
 18 
 12 
 18 
 15 
 12 
 12 
 12tol8 
 
 18 
 12 
 24 
 
 18 
 15 
 2 ft. 
 apart 
 Hedge 
 or 
 Clump 
 18 
 15 
 18 
 
 12 
 18 
 
 24 
 12 
 
 9 
 
 18 
 12 
 
 12 
 9 or 13 
 
 18 
 18 
 
 36 
 
 18 
 
 
 Indoors, Mar. 22 to 29. 
 Garden, May 5 to 12. . . 
 May 8 to 12 ... . 
 
 3 Bachelor's Button, blue.. 
 3 Balsam, mixed, red, 
 white, pink 
 
 May 8 to 12. . 
 
 3 Blue sage, grayish, blue. 
 
 1 California Poppy, yellow 
 2 Calliopsis, orange, yel... 
 2 Calendula, orange, yel... 
 1 Candytuft white 
 
 Indoors, Mar. 25 to 31. 
 Garden, May 8 to 15 
 April 20 to 25 
 April 20 to May 5 
 
 April 20 to May 5. . 
 April 15 to 30 
 March 1 to April 1. 
 May 1 to 10 
 
 2 Carnation mixed 
 
 4 Celosia, purplish, red.... 
 1 Dwarf Celosia, purple, r'd 
 
 1 Chinese pink, red & pink 
 3 Cosmos, mixed 
 
 *Indoors, Mar. 25 to 
 Apr 5 
 
 "Indoors, Mar. 21 to 25 
 *Indoors, March 25 to 
 April 10 
 
 Cypress vine, red, white. 
 2 Four o'clock, mixed 
 3 Gaillardia, mixed 
 
 Garden, May 1 to 15.. 
 May 10 to 15 
 
 April 10 to 20 
 
 April 25 to May 5 
 
 Gourds (vine) white 
 
 May 10 to 15 
 
 4 Kochia, deep red 
 
 Indoors, April 1 to 15. 
 Garden, May 10 to 15. 
 
 April 20 to May 10 
 April 20 to May 10 
 May 8 to 12 
 
 3 Larkspur mixed 
 
 3 Linum, blue 
 
 2 Marigold Tall, brown, red 
 1 Marigold Dwarf, brown, 
 red, yellow 
 
 May 8 to 12 
 
 2 Mignonette, yellowish, 
 brown 
 
 May 8 to 12 
 
 4 Morning Glory vine, 
 white, red, purple, blue 
 2 Nasturtium, orange, yel. 
 
 1 Pansy, purple, white, yel. 
 
 2 Petunia, purple, white, 
 pink 
 
 April 15 to 20 
 
 April 15 to 20 
 Indoors, Feb. 20 to Mr. 1 
 Garden, May 10 to 15. . 
 
 2 Phlox, mixed 
 
 Indoors, Mar. 15 to 20. 
 Ga/den, May 5 to 15. .. 
 Ap 'il 1 to 15 
 
 2 Poppy, mixed 
 
 1 Portulaca, mixed 
 
 Api'il 20 to 30 
 
 3 Salvia, orange, red 
 
 Indoors, Mar. 25 to 31. 
 Garden, May 5 to 15. .. 
 May 10 
 
 3 Scabiosa, mixed 
 
 4 Scarlet runner, red and 
 white 
 
 TVTfl v 1 
 
 2 Snap dragon, mixed 
 
 Indoors, Mar. 21 to 30. 
 Garden, May 10 to 15. . 
 
 *Plant in garden May 10 to 15. 
 
474 
 
 STUDIES IN SCIENCE 
 
 Name Color 
 
 Date to Plant 
 
 ; <u Distance Inches 
 
 S'SJIn Row 
 5i3l Of Rows 
 
 2 Stocks mixed 
 
 May 10 
 
 % 
 4to6 
 
 K 
 K 
 
 % 
 
 l 
 H 
 
 8 
 15 
 12 
 3 
 2 
 
 12 
 12 
 
 12 
 12 
 
 12 
 24 
 18 
 9 
 24 
 
 18 
 18 
 
 18 
 
 Vine 
 18 
 
 4 Sunflower (tall) yellow.. 
 3 Sunflower (dwarf) yel. . 
 1 Sweet alyssum, white. . . 
 4 Sweet peas mixed 
 
 May 10 to 15 
 
 May 10 to 15 
 
 April 1 to 10. . . 
 
 April 1 to 10 
 
 2 Sweet William, red and 
 white 
 
 Feb 15 to May 10 
 
 1 Verbena, mixed 
 
 Indoors, March 9 to 12 
 Garden, May 10 to 15. 
 Indoors, Max. 28 to 31. 
 Garden, May 10 to 15. . 
 
 In Fall or Mar. 1 to 5 . 
 May 8 to 12 
 
 2 Vinca, purple, pink and 
 white 
 
 4 Wild cucumber vine, 
 white 
 
 3 Zinnia, mixed 
 
 
 
 Where to plant. The best place for your annuals 
 is a plot in or near the vegetable garden. Do not 
 make flower beds in the lawn. If you have not begun 
 to plant shrubs around the foundation of the house, 
 you may find a spot where asters, sweet peas, nastur- 
 tiums, and some others will do well, but this is not 
 the best place for them. Pansies and ferns grow well 
 around the foundation of the house. 
 
 Successful planting includes: 
 
 1. A careful preparation of the seed-bed. The soil 
 should be fine and mellow. 
 
 2. In most cases the seeds should be planted in 
 rows, and, if in beds, they should be elevated slightly 
 above the garden level. 
 
 3. Do not plant the seeds very deep. A good gen- 
 eral rule to follow is to plant a seed to the depth 
 of four times its diameter. 
 
 4. Firm the soil well over the seeds. This may be 
 
LANDSCAPE GARDENING 475 
 
 done with the back of the hoe, a board, or by step- 
 ping upon the rows. 
 
 5. The distance between the rows must be gov- 
 erned by the size of the plants. See Planting Table. 
 
 6. If you use annuals for borders in the yard or 
 garden, be careful to plant together colors that 
 harmonize. The height of the plants must also be 
 considered. You can make a very pretty informal 
 border with annuals, if you are not ready to begin the 
 planting of shrubs and perennials. Instead of shrubs 
 use castor beans, kochia, cosmos, tall celosia, and 
 sunflowers. 
 
INDEX 
 
 Air, Composition of, 385, 386, 387 
 
 Diseases in, 403 
 
 Moisture in, 405 
 
 Pressure of, 388, 390 
 Alfalfa, 58 
 Aphids, 208 
 Apple, The, 265 
 
 Picking, Storing and Market- 
 ing, 268 
 
 Study of, 265 
 
 Varieties of, 267 
 Asters, 28 
 
 Bacteria, 239 
 Barometer, Uses of, 389 
 Bath, The, 353 
 Beans, Study of, 169 
 Birds, 436 
 
 Care of, 447 
 
 Enemies of, 446 
 
 Families of, 440-444 
 
 Groups of, 438 
 
 Lists of, 450 
 
 Part of a, 438 
 
 Shore, 444 
 
 Value of, 445 
 Blood, Circulation of, 399-401 
 
 Composition of, 499 
 Blue-grass, 56 
 
 Study of, 453 
 Braconids, 225 
 Bread, Making, 240 
 Breathing, Hygiene o.f, 402 
 
 Burdock, 72 
 Butter, 294 
 Butterfly, The, 204 
 
 Cabbage Worm, 203 
 Candle, The, 325 
 
 Power of, 328 
 Carbohydrates, 130 
 Cattle, 283 
 
 Breeds of, 287, 290 
 
 Care of, 288 
 
 Food of, 288 
 
 Housing, 291 
 
 Value of, 298 
 Cellulose, 123 
 Chickens, 421 
 
 Breeds of, 426 
 Clinometer, 411 
 Chlorophyll, 126, 127 
 Clover, 58 
 
 Clouds, Forms of, 414 
 Clubs, Boys and Girls, 147 
 Cold Frames, 145 
 Combustion, In Air, 375 
 
 In Oxygen, 376 
 Composites, 24, 28 
 Conduction of Heat, 377 
 Convection Currents, In Air, 368, 
 369 
 
 In Chimney, 370 
 
 In Wind, 371 
 Cooking, 132 
 Corn, 32 
 476 
 
INDEX 
 
 477 
 
 Selecting and Storing Seed 
 Corn, 42 
 
 Types of, 44 
 Cotton, 60 
 Cow, Beef, 286, 290 
 
 Dairy, 285, 287 
 
 Parts of a, 284 
 Cow-peas, 38 
 Crab-grass, 70 
 Cucumber, 12, 165 
 Cucumber Beetles, 211 
 Cucurbitacae, 13 
 Cucurbits, 11, 165 
 Cuttings, Hard Wood, 261 
 
 Propagating Plants by, 255 
 
 Soft Wood, 261 
 
 Dandelion, 71 
 Digestion, 133 
 Disinfectants, 251 
 Disk Flowers, 27 
 Drainage, 105, 106, 107, 108 
 Drupe, A, 270 
 
 Eating, Hygiene of, 135 
 Evaporation of Liquids, 357, 358 
 Eye, The, 336 
 
 Care of, 337 
 
 Parts of, 336 
 
 Farm Crops, 32 
 Fats, 131 
 Feathers, 423 
 Fertilizers, 118 
 Fireless Cooker, 377 
 Flowering Plants, 22 
 
 List of Annuals, 471 
 
 List of Perennials, 470 
 
 Outline of Study of, 23 
 
 Parts of, 22 
 
 Planting Table for, 473 
 
 Wild, 28 
 Foods, 130 
 
 Care of, 137 
 
 Classes of, 130 
 Forestry, 196 
 Forests, 196 
 Foxtail, 70 
 Fruit, 265 
 Fruit Trees, 265, 272 
 
 Care of, 280 
 
 Fuels, How They Burn, 372 
 Fungi, 228 
 
 Bracket, 232 
 Furnace, Hot Air, 366 
 
 Garden, The, 139 
 
 Pests of, 202 
 Glaciers, Work of, 101 
 Golden-rod, 28 
 Gourd, 13 
 Grafting, 274 
 
 Cleft, 277 
 Grasses, 52, 56 
 
 Kinds of, 452 
 
 Health, 130 
 
 Air in Relation to, 395 
 
 Bacteria and, 250, 252 
 
 Foods and, 130 
 
 Milk in Relation to, 297 
 
 Water in Relation to, 346 
 Heat, 364 
 
 Conduction of, 377 
 
 Radiant, 379 
 
 Regulation of in Body, 361 
 Heating, 364 
 Hedges, 466 
 Hogs, 309 
 
 Breeds of, 313 
 
478 
 
 INDEX 
 
 Care of, 314 
 
 Diseases of, 316 
 
 Food of, 315 
 Home Projects, 139 
 
 Beans and Peas, 169 
 
 Calf, 298 
 
 Colt, 309 
 
 Corn, 176 
 
 Cucumbers and Other Cucur- 
 bits, 165" 
 
 Fruits, 282 
 
 Lamb, 323 
 
 Lawn, 457 
 
 Oats, 183 
 
 Onions, 160 
 
 Pig, 317 
 
 Potatoes, 155 
 
 Poultry, 433 
 
 Root Crops, 152 > 
 
 Shrubs, 460 
 
 Tomatoes, 148 
 
 Wheat, 187 
 Horses, 299 
 
 Care of, 305 
 
 Training, 308 
 
 Types of, 299 
 
 Uses of, 301 
 Hotbed, Making a, ,141 
 House-fly, 218 
 Humus, 96, 101 
 
 Ice, 354 
 
 Artificial, 360 
 Ice Cream, Making, 383 
 Ichneumons, 225 
 Insects, 201 
 
 Beneficial, 223 
 
 List of Common Pests, 221 
 
 Poison Sprays for, 222 
 Irrigation, 108 
 
 Ladybird Beetles, 224 
 Lamp, The Gas, 332 
 
 The Kerosene, 329 
 Landscape Gardening, 451, 463 
 
 Rules of, 460 
 Lawn, The, 452, 456 
 Leaves, 86, 91 
 
 Parts of a, 87 
 Legumes, 52, 56 
 Light, 325 
 
 Electric, 334 
 
 In Early Times, 328 
 Lighting, 325 
 Lungs, Structure of, 399 
 
 Meadow Grasses, 53 
 
 Melon, 13 
 
 Milk, Care of, 295 
 
 Composition of, 291 
 
 Separation of, 292 
 
 Testing, 296 
 Mold, 233, 235 
 Mosquitoes, 214 ^ 
 
 Malaria Transmitted by, 217 
 Mushroom, 228, 230 
 
 Native Woods, 195 
 
 Oats, 183 
 Onions, 160 
 
 Oxidation in Body, 351 
 Oxygen, Behavior of, 376 
 How to Make, 374 
 
 Parasite, 236 
 Pasture Grass, 53 
 Peach, The, 271 
 Perennials, 27 
 Petunia, 7 
 Pigweed, 68, 70 
 
 
INDEX 
 
 479 
 
 Plants, 110 
 
 Food of, 112 
 
 Propagating by Cuttings, 255 
 
 Transpiration of, 116 
 
 Transplanting, 259 
 
 Work of, 120 
 Pome, A, 270 
 Potatoes, 16 
 
 Sweet, 19 
 Poultry, 421 
 
 Breeds of, 426 
 
 Care of, 432 
 
 Feeding, 431 
 
 Housing of, 428 
 Proteids, 131 
 Pruning, 281 
 Puffballs, 229, 230 
 Pumpkins, 13 
 Pumps, 391 
 
 Making a, 392 
 
 -adiant Heat, 379 
 Ray Flowers, 27 
 Refrigerator, The, 382 
 Respiration, 397 
 Rotation of Crops, 117 
 
 Seed-bed, Preparing the, 146 
 Seed, The Making of a, 30 
 Separation of Milk, 292 
 Sewage, Disposal of, 349 
 Sheep, 318 
 
 Care of, 321 
 
 Types of, 320 
 Shrubs, 457 
 
 Care of, 466 
 
 Rules in Planting, 460 
 
 Table of, 460 
 Skin, Care of, 352 
 Smartweed, 70 
 
 Soils, 95 
 
 Composition of, 96 
 
 Origin of, 98 
 
 Water in, 103 
 Soy-beans, 58 
 Smuts, 235 
 Spraying, 282 
 Springs, 345 
 Squash, 11 
 Squash-bug, 207, 209 
 Sun, Observations of, 409-413 
 Sunflower, 25 
 Swine, 309 
 
 Breeds of, 313 
 
 Care of, 314 
 
 Teeth, The, 136 
 Temperature, 409 
 Thermometer, The, 379 
 Thistle, 72 
 Tillage, 116 
 Timothy, 57 
 Tissue, Kinds of, 350 
 Toadstool, 228, 230 
 Tomato, 8 
 
 Canning the, 150 
 Tomato-worm, 206 
 Transplanting, 259 
 Trees, 84, 189 
 
 Care of, 199, 280 
 
 Food of, 194 
 
 Fruit, 265, 272 
 
 Outline for Study of, 89 
 
 Parts of a, 84 
 
 Types of, 90 
 
 Uses of, 197 
 Twig, 88, 273 
 
 Parts of a, 88, 192 
 
 Vacuum Cleaner, The, 393 
 Vapor, Water, 356 
 
480 
 
 INDEX 
 
 Vegetables, 8 
 Ventilation, 395, 396 
 Vines, 467 
 
 List of, 468 
 Vivarium, A, 201 
 
 Water, 103 
 
 Capillary, 104, 113 
 Evaporation of, 357, 358, 362, 
 
 363 
 
 Ground, 103, 104 
 How to Secure Pure, 347 
 Need of, 350 
 Source of Supply in School, 
 
 339 
 
 Weather, 406 
 
 Map of, 418, 419 
 
 Record of, 407, 408 
 Weeds, 67 
 
 Getting Rid of, 75 
 
 List of Common, 77 
 
 Outline Record for Study of, 67 
 Wells, 342-344 
 Wheat, 46 
 
 Varieties of, 49 
 Winds, 417 
 Wool, 322 
 
 Yeast, 239 
 

 
/ 
 
 YB 56827 
 
 413117