c 
 
 The Miami Bulletin 
 
 Seriks VII. Mx\Y, 1908. Number 1 
 
 Teachers’ Bulletin No. 2, Department of 
 Agricultural Education, Ohio State Normal 
 College, Miami University, Oxford, Ohio 
 
 EXPERIMENTAL STUDIEo 
 OF PLANT GROWTH 
 
 B. M. DAVIS 
 
 Published Monthly by Miami University 
 
 And Entered at Postoffice^ Oxford^ Ohio, as Second Class Mail Matter 
 
Work of the Department of Agricultural Educa- 
 tion of the Ohio State Normal College 
 of Miami University. 
 
 The organization of this department began in January 
 1907. The work undertaken is two fold. 
 
 1. To help teachers and prospective teachers who may 
 wish to make use of practical nature-study or ele- 
 mentary agriculture in the public schools : 
 
 (a) By means of direct instruction in class- 
 room and laboratory. 
 
 (b) By means of correspondence. The depart- 
 ment is often able to give helpful suggestions in 
 answer to letters of inquiry, especially in regard 
 to references to literature on special subjects. 
 
 (c) By means of conferences with teachers and 
 members of school boards as to plans and methods 
 of taking up the work in township schools. 
 
 2. To co-operate with teachers in typical country 
 schools, particularly in village or township high 
 schools in farming communites, to determine by 
 actual experiment what phases of agriculture as a 
 school subject are best adapted to the needs of such 
 schools, and how the subject should be handled to 
 the best advantage under average country school 
 conditions. 
 
 Efficient instruction in agriculture is desirable in 
 small high schools of rural districts not only on ac- 
 count of its educational and practical value, but also 
 because the teaching force of the ungraded schools 
 is chiefly recruited from these high schools. The 
 problem of agricultural instruction in the village or 
 township high school, therefore, is'fdoubly impor- 
 tant, and deserves the most careful consideration of 
 all concerned. 
 
INTRODUCTION. 
 
 '‘But the great object of the teachers of ‘science’ 
 should be to teach the art of experimenting - the meaning 
 and use of an experiment. The essential first step in an ex- 
 periment Js to have a clear conception of the motive of the 
 quest in which it is proposed to engage.” * 
 
 It is in the spirit of this conception of science teaching 
 that the following studies of plant growth have been brought 
 together. 
 
 After considerable observation the writer is convinced 
 that introductory science, and to a certain extent all science 
 as taught in the average small high school fails to do more 
 than give a certain amount of scientific information. In 
 many schools it is taught wholly from text-books. Fortun- 
 ately these text-books are generally well written, and the 
 statements contained in them are usually scientifically cor- 
 rect. But in order to learn to make use of information from 
 books one must learn from actual experience how such 
 information is obtained. 
 
 Science in the small high schools must be taught by 
 teachers who divide their time with other subjects, and who 
 are sometimes unfortunate in their own scientific training. 
 Well equipped laboratories are out of the question for most 
 of these schools. Such conditions are often made an excuse 
 for the inferior character of work done. 
 
 On the other hand, bright and active boys and girls at- 
 tend these schools. Many of these children come from 
 farms where nature is dealt with most intimately. They are 
 familiar with plant and animal life, and are used to doing 
 things. 
 
 With such children to work with, well equipped labora- 
 tories land expensive [apparatus are not needed, at least for 
 their introductory science. The chief concern is to get the 
 children to work on problems which have to do with things 
 already familiar, and the solution of which will give signifi- 
 cance to these things. 
 
 Such a course of study might be called agriculture, or 
 botany in so far as it concerns plants, or physics in so far as 
 
 * Henry E. Armstrong, “The Teaching of Scientific Method,” pp. 
 204-205. New York : The Macmillan Co. 
 
 3 
 
it cmicerns soil and farm machinery. The name is unim- 
 portant, but since agriculture deals fundamentally with 
 plants and the soil the use of this name for such work maybe 
 desirable. 
 
 The v/riter believes work of the character just sug- 
 gested should give the child his first training in science, 
 whether in the later grammar grades or in the first year of 
 high school. Such a procedure is practical, for it is in the 
 reach of the average school; it is also practical in another 
 way, for it will have the support and interest of the patrons, 
 it is pedagogical, for it enlists the child’s own activities by 
 enabling him to ‘Team by doing”; it is scientinc for it puts 
 emphasis on experiment and correct method of research, 
 rather than upon scientific information. 
 
 The experimieiital studies of “Soil and its Relation to 
 Plants” (7*) have been used by several small high schools in 
 farming communities, and many of the simpler studies have 
 been used in the grammar grades of similarly situated 
 schools. The success of this work as indicated by the inter- 
 est of the pupils, both boys and girls, and of the parents, has 
 encouraged the writer to prepare the present bulletin deal- 
 ing with plant growth. 
 
 The experim^ents outlined have all been tried, under the 
 writer’s direction, by pupils of various ages and capacities, 
 and seem well adapted to pupils of the first year high school. 
 
 The familar fact that when seeds are planted they will 
 develop sooner or later, in the ordinary course of events, in- 
 to plants furnishes a basis for inquiry by means of experi- 
 ment. What takes place from the time the seed is planted 
 until the plant appears? When this question is resolved into 
 a series of questions in the form of problems, and these an- 
 swered by means of observation and experiment, some of the 
 most important facts of plant growth will be realized and 
 will be made to give meaning to many familiar practices in 
 plant propagation. At the same time, and yet more impor- 
 tant, will be the insight into and practical training in the 
 scientific method of inquiry. To develop ability to use this 
 method is, after all, the true aim of science teaching, and 
 
 * Note — Figures refer to references on pp. 31. 
 
 4 
 
science, in the words of an eminent scientist, is but “human 
 experience tested and put in order. 
 
 The exercises in plant growth outlined in this bulletin 
 have been adapted from various sources. Some of the experi- 
 ments are classical in plant physiology and appear with cer- 
 tain modifications in all text-books dealing with the subject. 
 
 The writer wishes to acknowledge the helpful sugges- 
 tions v/hich he has received from “Plant Production” by D. 
 J. Crosby, “Beitraege ZurMethodik des Botanischen Unter- 
 richts” by F. Schleichert, and especially from “Experiments 
 with Plants” by Dr. W. J. V. Osterhout. The figures which 
 contribute greatly to the clearness of many of the exercises 
 have all been taken from “Experiments with Plants.” For 
 kindly permitting him to use these, the writer is indebted to 
 Dr. Osterhout and to The Macmillan Co. 
 
 Suggestions to Teachers as to Method. 
 
 In pursuance of the general plan already indicated, the 
 following exercises are intended to persenta series of simple 
 experiments dealing with plant growth. Following the pre- 
 liminary exercises I to V, the solution of each problem 
 usually presents'another for investigation. 
 
 The title of each exercise is a statement of the subject 
 to be studied by means of experiment. This is followed by 
 a brief account of how to conduct the experiment or experi- 
 ments in order to find an answer to the problem suggested in 
 the title. 
 
 It is important that the pupil should have a clear concep- 
 tion of the problem and some directions as to how-to proceed 
 in its solution. His success will depend upon the clearness 
 of his conception of what he is to find out, and also upon the 
 faithfulness with which he carries out the details of the ex- 
 perim.ent. In order better to insure this, each pupil should 
 keep a record of what he undertakes. 
 
 Such a record should contain : 
 
 1. Statement of the problem or object of the exercise or 
 experiment. 
 
 2. Statement of the material, apparatus, etc., used. 
 
 3. Statement of the procedure in workng out the problem 
 
or experiment. This will include setting up of apparatus, 
 if any is used, and may be illustrated by diagrams. 
 
 4. Observations. A careful record of observations 
 should be made, including time of observation (day and 
 hour) . 
 
 5. Statement of results. This is a sort of final sum- 
 mary of observations. 
 
 6. Conclusions. Sometimes this and (5) may be includ- 
 ed in one statement. 
 
 A great deal depends upon the care of experiments. As 
 most of the exercises will be concerned with living plants or 
 seeds it is necessary to make daily observations in order (a) 
 to note the progress of the experiment and (b) to see that 
 the conditions are kept favorable, especially as to moisture 
 and warmth v/here these are concerned. The habit of clear- 
 ing up the experiment as soon as it is finished should be en- 
 couraged. By this is meant cleaning bottles, jars, dishes, 
 etc., and putting away apparatus no longer needed. 
 
 All material and apparatus, and also reference books and 
 pamphlets should be provided as far as possible by the time 
 the course is begun. Some of the material for exercises will 
 require preparation by the teacher sometime in advance of 
 the work by the pupil. As soon as the work is fairly begun 
 by the pupils the teacher will find it only necessary to give 
 a few simple directions, and provide material and apparatus, 
 the pupils will do the rest. 
 
 6 
 
EXPERIMENTAL STUDIES OF PLANT GROWTH. 
 
 I. General Study of Germination. 
 
 (a) Under favorable conditions. 
 
 Plant some radish seeds in pot of sand or garden 
 soil. The depth of planting should not be over one- 
 fourth inch. Keep seeds in warm place and 
 sprinkle with water each day. 
 
 (b) Lacking water. 
 
 Prepare some more seeds in the same way but use 
 dry soil and do not add water. 
 
 (c) Lacking warmth. 
 
 Prepare and care for seeds as in (a) but keep in a 
 cool place. If weather is cool the seeds may be 
 left out of doors. If weather is warm keep in 
 a refrigerator or in ice-box made after the plan il- 
 lustrated in Fig. 1. 
 
 (d) Lacking air. 
 
 Put some seeds in bottle and then fill with water 
 that has been boiled (to drive out air) and cooled. 
 Cork tightly and seal by running paraffine around 
 the cork. Keep in warm place. 
 
 1. Arrangement for keeping seeds on ice: the space be- 
 tween the boxes is filled with sawdust, which also 
 surrounds the ice. 
 
 When seeds have germinated in (a) examine seeds in 
 (b), (c) and (d), and compare with growth in (a). The 
 
 7 
 
results observed will indicate conditions necessary for germi- 
 nation of seeds viz., water, warmth and air. 
 
 II. Vitality of Seeds. 
 
 Even under favorable conditions some seeds will not 
 germinate. It is important before planting a large number 
 of seeds to test them to see what per cent will germinate. 
 Test the seeds of the ears of corn. Make a tester out of small 
 cigar box. For details of making the'test see 5, P. 59, and 
 4, Fig 7. 
 
 III. Decay of Seeds. 
 
 Seeds that germinate slowly, especially if they are 
 large, often decay instead of germinating. This is due to 
 the action of bacteria and m.oulds. The value of formalde- 
 hyde in preventing this action may be shown as follows : 
 
 (a) Cover ten beans with a one per cent solution of 
 formaldehyde for one hour. After rinsing them to re- 
 move the formaldehyde put them in a tumbler of v/ater 
 and leave in a warm place. 
 
 (b) Ten other beans that have not been treated with 
 formaldehyde should be left in a tumbler of water as in 
 (a). After two or three days compare (a) and (b). The 
 first stages of decay will be indicated by cloudiness 
 of the water. If left long enough the seeds in (a) , pro- 
 vided there is air enough in the water, will germinate. 
 Those in (b) will decay. 
 
 IV. Structure of Typical Seeds. 
 
 To facilitate study of seeds, they should be left in water 
 over night or longer. 
 
 (a) Lima bean. 
 
 1. Note markings on surface : 
 
 a. Scar or hilum where seed was attached to pod. 
 
 b. Near hilum on middle line of bean a small opening, 
 the micropyle, 
 
 2. Remove the covering, seed-coat or testa. Near the 
 hilum a small pointed body, the caidicle will be seen. 
 Note its position with reference to the micropyle. 
 
 8 
 
Separate the halves or cotyledons, observe that the 
 caulicle bears two small leaves, the plumule. 
 
 The cotyledons, caulicle and plumule constitute the 
 embryo, 
 
 (b) Castor-bean. 
 
 1. Remove the testa and note the inner seed-coat, the 
 endopleura which encloses the kernel. 
 
 2. Expose the embryo by split- 
 ting the kernel longitudinal- 
 ly. Make out the parts as 
 shown in Fig. 2: (c) cauli- 
 cle; (si) cotyledons; (e) en- 
 dosperm; (ca) caruncle, a 
 protuberance on testa. 
 
 3. The material of the kernel 
 surrounding the embryo is 
 the endosperm. 
 
 2. Castor-bean open, showing en- 
 dosperm (e), caulicle (c), 
 seed-leaves {si) and caruncle 
 
 (ca). 
 
 (c) Corn. (A grain of corn is a fruit, not a true seed.) 
 
 1. Note general shape. The groove on one side marks 
 position of embryo. 
 
 2. Cut grain lengthwise so as to show parts as indicated 
 in Fig. 3. 
 
 Make out the parts by comparing cut surface with Fig. 
 3: (c) caulicle; (pi) plumule (1) 
 seed-leaf or cotyledon; (e) en- 
 dosperm. 
 
 All seeds, except the seeds of con- 
 ifers, are of one of these types. In 
 
 (a) the food material is stored in the 
 cotyledons of the embryo itself ; in (b) 
 and (c) the food material is stored out- 
 side of the embryo and is called en- 
 dosperm. 
 
 Drawings should be made of (a), 
 
 (b) , and (c) showing and naming 
 parts. 
 
 Corn cut lengthwise, show- 
 ing cavilicle (c). Plumule 
 {pD, seed-leaf (/) and 
 Endosperm (e). 
 
 V. Balance. 
 
 In order to perform several of the experiments outlined 
 a balance will be necessary. If it cannot be bought one may 
 
 9 
 
be easily constructed from a rib of an old umbrella as shown 
 in Fig. 4. The rivet which unites the long and short arms 
 of the wire should be taken out, and a fine needle used in its 
 place. Tops of baking powder cans will make good pans. 
 These should be attached as shown in figure by means of silk 
 thread or fine wire. The two arms of balance should be 
 exactly the same length, and points of attachment for the 
 
 4. A home-made balance constructed of umbrella wire; it can be made sensatve 
 to a tenth of a gram. 
 
 pans should be equi-distant from the needle. The two sides 
 may be made to balance by trimming edges of pans. Metric 
 weights should be bought if possible. Weights may be made 
 by trimming pieces of lead to correspond to the weights of a 
 druggist. 
 
 Another way of making a balance is described in 5, Pp. 
 28-30. 
 
 VI. Relation of the Micropyle to Absorption 
 of Water. 
 
 1. Put a dry bean in a flask or test-tube partly filled 
 with water. Heat gently over a gas or alcohol flame. 
 Heat expands air within the bean. Note where the 
 air escapes as indicated by small bubbles leaving the 
 seed. 
 
 2. Gently press a seed that has been soaked several hours 
 
 lO 
 
in water, and note if water is forced out at same 
 point as the air in 1. 
 
 3. Select thirty grains of corn. Fill a cigar box two- 
 thirds full of sand, and keep it moist during the pro- 
 gress of the experiment. 
 
 Place seeds in rows of 10 each as follows : 
 
 Row 1, with points of seeds inserted in sand. 
 
 Row 2, "with broad end of seed in sand. 
 
 Row 3, with five seeds lying on smooth side and five 
 lying on side with groove. 
 
 Note time of germination of seeds in each row and ac- 
 count for the difference noted. Remember that the 
 opening in the corn, corresponding to the micropyle 
 in function , is at the pointed end. 
 
 VII. Water and Germination. 
 
 In the preliminary studies of germination (I), it was 
 found that seeds would not germinate without water. Our 
 first problem is to determine more exactly the relation of 
 water to the germinating seed. Does water enter the seed? 
 
 Weigh two beans of nearly the same size. Put one (a) 
 in water, and leave the other (b) dry. After 24 hours com- 
 pare (a) with (b): (1) as to weight; (2) as'tosize, by tracing 
 outline of each on paper. 
 
 VIII. Changes in Appearance of Seed During 
 Absorption of Water. 
 
 Place lima bean in water and observe at intervals of 
 one hour for several hours. A drawing should be made at 
 each observation showing appearance at that time. Fig. 5. 
 
 5. A Bean placed in water, showing successive stages in the process of wrinkling; the 
 wrinkling indicates where the water enlers and how it spreads inside the cover. 
 
 IX. Absorption of Water by the Seed. 
 
 Select 10 seeds (beans) of nearly the same size and 
 weight. Divide them into sets of five. Designate the sets 
 as (a) and (b). Weigh each set. 
 
 II 
 
1. Cover seeds of (a) entirely with water. 
 
 2. Arrange seeds of (b) in water so that the hilum of 
 each seed will be exposed and free from contact with 
 water. Seeds may be held in position with hilum up 
 by means of a strip of bent lead or tin (U shape) or by 
 means of a piece of coiled wire as shown in Fig 6. 
 Care should be taken in the selection of seeds, avoid- 
 ing seeds that have injured seed-coats. 
 
 6. An arrangement for holding seeds while under water. 
 
 After from four to six hours carefully weigh (a) and (b). 
 Before weighing water must be carefully drained off, and 
 seeds dried by means of blotting paper or cloth. 
 
 A comparison of (1) with (2) will show that most of the 
 water enters in the region of the micropyle and that part 
 enters through the seed-coat. 
 
 X. Absorption of Water Through the Seed-Coat. 
 
 Remove the seed-coats of several pumpkin seeds. Each 
 seed-coat should be in nearly entire halves and free from 
 openings or cracks. 
 
 Into each half of seed-coat, thus prepared, put a few crystals 
 of sugar. (There should be at least six halves. ) Arrange 
 part of them on water so as to float like boats; put the 
 rest on a dry surface as a control experiment. If^the seed- 
 coats permit water to pass through this fact will be indicat- 
 ed by the sugar dissolving. 
 
 The rate that the sugar crystals pass into solution is a 
 rough measure of the passage of water through the seed- 
 coat. Compare rate in seed-coats of several kinds of seed : 
 pumpkin, caster bean, almond, walnut and other large seeds. 
 If difference of rates is noticed, tabulate results. 
 
 XL Importance of Embryo or Endosperm in Absorption 
 of Water Through the Seed-coat. 
 
 Prepare several seed-coats as' in X but use pieces of 
 embryo (or endosperm in such seeds as castor bean)instead of 
 
 12 
 
sugar crystals. Weigh pieces of embryo or endosperm at be- 
 ginning of the experiment, and at one hour or longer inter- 
 vals to determine whether or not water is absorbed. 
 
 XIL Course of Water on Entering the Seed. 
 
 Put seeds in some red ink or solution of eosin (red dia- 
 mond dye may be used. ) Several seeds should be used. Re- 
 move a seed at one-half to one day intervals. Examine by 
 splitting seed and noting portions colored. Make diagram. 
 Observe relation the path of water seems to have to the 
 embryo plant. (Caulicle in case of bean, and other seeds 
 having fleshy cotyledons.) 
 
 XIII. Amount of Water Necessary for Seeds 
 to Germinate. 
 
 In each of several pint or quart mason jars put ten dry 
 bean seeds. Cover with dry sand to depth of one-half inch. 
 Number (1), (2), (3), (4), etc. Add small quantity of water 
 (5 cubic centimeters) to (1) ; twice as much to (2) ; three 
 times as much to (3) ; etc. 
 
 The beginning of germination will be noted when the 
 caulicle begins to make its appearance. 
 
 The amount of water put in the jar where seeds first as- 
 sume above appearance (caulicle protruding) is approximate- 
 ly the minimum amount of water needed for germination. 
 Remove one of the seeds that is just germinating; weigh; 
 drive off moisture by means of heat; weigh until weight is 
 constant. From these weights determine the amount of 
 water in the seed when the caulicle appears. Determine 
 also per cent of water in seed at this stage of germina- 
 tion. 
 
 XIV. Effect of Moist Air on Germination of Seed. 
 
 Using a mason jar, cover the bottom with water and 
 support some seeds (radish and beans) by means of wire 
 netting as shown in Fig. 7. As this experiment must be 
 under observations several weeks, it will be necessary to 
 treat the seeds with formaldehyde to prevent mould. 
 
 It is desirable also to weigh the seeds before putting 
 them in the jar. At conclusion of experiment (i. e. after 
 
 13 
 
4-6 weeks) weigh seeds, and compare with original weight. 
 Calculate amount of water absorbed. Some seed-coats, e. g. 
 those of radish seeds absorb water 
 readily. 
 
 If seeds germinate in moist air, 
 it is important that they be stored 
 in a dry place. 
 
 XV. Amount of Air Necessary 
 for Germination. 
 
 We have already seen in exer- 
 cise I that air is rkeeded for seeds 
 to germinate. 
 
 Partly fill six homo-vials with 
 sand, at different depths ranging 
 from one-half inch in first to 
 within less than one-fourth inch of 
 top in last. Do not leave any free 
 water above the sand. When seeds 
 begin to germinate in any of the 
 vials examine the others. . 
 
 XVI. Test for Carbon Dioxide. 
 
 We are familar with the fact that animals need air (ox- 
 ygen), and that in breathing (respiration) they give off car- 
 bon dioxide. 
 
 Prepare limewater as follows : Pour water on unslack- 
 ed lime and allow to stand several hours. Filter the liquid 
 or strain through cotton. Keep liquid (limewater) in a 
 well stoppered bottle. When carbon dioxide comes in con- 
 tact with lime water, the solution becomes cloudy. Carbon 
 dioxide unites with the lime making insoluble carbonate of 
 lime. Test air from lungs for carbon dioxide by blowing 
 breath through glass tube into a bottle of limewater. Note 
 cloudy or'milky appearance of liquid. This is a common test 
 for carbon dioxide. 
 
 
 7 Seeds placed in a saturated 
 atmosphere. 
 
 14 
 
XVII. Carbon Dioxide Given Off by Germinating Seeds. 
 
 Put a quantity of soaked peas or beans in a mason jar 
 with a vial of lime water (leave vial open), and seal jar 
 tightly. For control experiment, ar- 
 range another jar with vial of lime 
 water surrounded by cotton or paper 
 instead of seeds. For arrangement 
 of experiment see Fig. 8. 
 
 After 24 hours examine the lime- 
 water in the two jars. If water in 
 the control experiment is clear or 
 nearly so, and that in the other jar is 
 covered with a thin white crust and 
 the water itself somewhat milky in 
 appearance, we must conclude that 
 carbon dioxide has been given off by 
 the germinating seeds. 
 
 . Apparatus foi determining 
 whether germinating seeds 
 produce carbon dioxide, 
 the vial is filled with lime- 
 water. (Seen in section.) 
 
 XVIIL Amount of Carbon Dioxide Given off During 
 Germimation, 
 
 The amount of carbon dioxide given off by a certain 
 mass of seeds in a certain time (24 hours) may be roughly 
 shown as follows: 
 
 1. Carefully fit a glass tube into each stopper of two 
 wide-mouthed, 6 ounce bottles. The stoppers must fit 
 closely to tubes and bottles so that no air can enter 
 bottles except through glass tubes. If rubber stoppers 
 of the right size are used they will probably fit with- 
 out any extra precaution. If cork stoppers are used 
 they should be soaked in melted paraffin, and after the 
 glass tubes are inserted melted paraffin should be ap- 
 plied around them. In each bottle the glass tube 
 should extend from about two inches outside nearly to 
 the bottom on the inside. 
 
 2. Fill two glass tumblers to a depth of one inch with 
 strong solution of lye (caustic soda or caustic potash.) 
 
 3. Fill one bottle to a depth of about two inches with 
 
 15 
 
germinating seeds. Seeds that have been soaking over 
 night will do. 
 
 4. Cork both bottles tightly with stoppers prepared as in 
 (1). Be careful that no air may enter at edge of stop- 
 per or around the glass tube of either bottle. 
 
 5. Invert each bottle over a glass of lye (2) so that the 
 end of the tube beyond the outside of stopper will re- 
 main below surface of lye. Secure bottle to glasses 
 by means of clamps and of pieces of string or rubber 
 bands. 
 
 The arrangement of apparatus 
 is shown in Fig 9. Lye (caustic 
 potash or caustic soda) absorbs car- 
 bon dioxide. If carbon dioxide is 
 given off by the germinating seeds, 
 it will be absorbed by the lye- The 
 lye will therefore rise in the glass 
 tube in proportion to the amount of 
 carbon dioxide dissolved. This 
 amount is the amount given off by 
 the seeds. The empty bottle and 
 solution of lye is a control experi- 
 ment. The cubic capacity of the 
 glass tube above the level of the 
 lye to the point where the lye ascends represents approxi- 
 mately the volume of carbon dioxide given off during the op- 
 eration of the experiment. If left longer than 24 hours the 
 lye will probably be drawn into the bottle with the seeds. 
 
 Note— If air in the room is very warm when the control 
 experiment is prepared, and afterwards becomes cool, the 
 air in the bottle will contract. Under such conditions the 
 lye will be drawn up into the tube and possibly over flow 
 into the bottle. The experiment, therefore, should be prepar- 
 ed in a cool place. 
 
 XIX. Effect of Drying on Subsequent Growth of 
 a Germinated Seed* 
 
 Allow several grains of corn or wheat to germinate until 
 caulicle is plainly seen. Separate into sets of 5 grains each. 
 Allow first set to dry 24 hours; the second, 48; the third, 72; 
 
 i6 
 
 9, Method of measuring the amount 
 of carbon dioxide produced by 
 germinating seeds, the tumblers 
 contain lye (control at the 
 right). 
 
the fourth, 96; at the end of these periods restore seeds to 
 favorable conditions. 
 
 Note minimum time seed may be exposed to dryness 
 without preventing subsequent growth. 
 
 XX. Influence of Depth of Planting on Germination. 
 
 Fill a quart mason jar to depth of one inch with garden 
 soil and place seed next to glass ; add another inch of soil and 
 plant the second seed; and soon until the topis reached. 
 The soil should be packed tightly around the seeds. Keep the 
 soil moist and the jar covered so as to exclude the light. 
 
 At end of one week or ten days make note of progress 
 of germination and growth. (5, P. 56.) 
 
 XXL Influence of Seed-coat on Germination. 
 
 Select twelve seeds of each of several kinds (pumpkin, 
 sweet-pea, four o’clock, peach, walnut, etc.) With each 
 kind of seed proceed as follows: Plant 6 seeds in moist soil; 
 6 seeds in moderately dry soil. Do the same with the other 
 six seeds having previously removed the seed -coats. 
 
 Note effect of removal of seed-coats on time of germina- 
 tion of each kind of seed. 
 
 Note also any other effect of removal of seed-coats as in- 
 dicated by difference in results. 
 
 XXII. Work Performed by Germinating Seeds. 
 
 Fill bottle with dry seeds and add as much water as bot- 
 tle will hold. Cork tightly and secure stopper by means of a 
 wire. Set away 24 hours and note result. 
 
 The force exerted by germinating seeds in first stage of 
 germination (period of water absorption) may be measured. 
 
 Fill fruit press half full of dry seeds. Attach spring 
 balance to arms of press so that any movement of arms will 
 be recorded by balance. Method of setting up experiment 
 will be readily seen by consulting Fig. 10. Place lower parts 
 of press in water. After two hours read pressure as indi- 
 cated by balance. After 24 hours take another reading. 
 
 Calculate area of piston of press, and from the arms of 
 press as levers calculate pressure exerted by 1 square inch 
 surface of the mass of germinating seeds. The pressure 
 
 17 
 
exerted at (b) which is the amount exerted on piston) is equal- 
 to distance in inches from (a) to (c) times weight indicated 
 by balance, divided by distance in inches from (a) to (b). 
 
 10. Appratus for demonstrating that swelling seeds exert pressure (a portion 
 of the wall is represented as cut away in order to show the seeds) . 
 
 In levers the distance of the power from fixed point times 
 power is equal to distance of weight from fixed point times 
 weight. 
 
 XXIIL Heat Generated by Germinating Seeds* 
 
 Although the rise in temperature in germinating seeds 
 is slight, it may be measured— provided conditions are favor- 
 able and great care is taken. 
 
 Test two thermometers to see if their readings are the 
 same when place side by side in (a) cool water, and (b) in 
 warm water. If they do not register the same, allowance 
 must be made for this difference in subsequent readings. 
 
 Fill a tumbler ( a) with seeds that have been soaking 
 about 24 hours. Fill another tumbler (b) with damp cotton. 
 
 Fit a thermometer in the center of a cardboard cover for 
 each tumbler. The bulbs of the thermometers should extend 
 
 i8 
 
to the center of the contents of the tumblers. The apparatus 
 with thermometers in place is shown in F‘g. 11. 
 
 11. Method of measuring the temperature of germinating geeds. 
 (control at right). 
 
 Take reaciings every 10-20 minutes. If there is a slight 
 rise of temperature in (a) and no rise in (b) the difference 
 must be due to heat of germinating seeds. The amount is not 
 likely to be over one degree. 
 
 XXIV. Importance of Cotyledon or Endosperm. 
 
 1. Germinate several grains of com and beans until 
 caulicles appear. 
 
 2. Fill two boxes with garden soil. Plant in one (a) two 
 grains of corn, and two beans. 
 
 Cut off part of the endosperm of two grains of corn 
 and part of the cotyledons of two of the beans. Plant 
 these in pot (b). 
 
 Give each pot the same care as to water and warmth. 
 Keep theTplants as they appear under observation for 
 at least two weeks, taking notes of appearance and 
 making measurements from time to time. The results 
 
 19 
 
of this exercise should show the importance of the 
 stored up food supply in the seed. 
 
 The importance of this may be further shown by 
 selecting seeds of different sizes. Plant them and 
 keep growing under favorable conditions. Observe 
 differences in growth. These differences, in the ear- 
 ly stages, will be due chiefly to difference in the 
 amount of food stored up in the seeds. Consult Fig- 
 ure on page 10 of 3. 
 
 XXV. Test for Starch. 
 
 Starch is one of the most important forms of food stored 
 up seeds. Its presence may be easily detected by means of 
 a solution of iodine. 
 
 Make a little starch paste by rubbing up a small quan- 
 tity of starch in cold water and then adding hot water. Di- 
 lute and add a few drops of solution of iodine. The blue 
 color that appears indicates the presence of starch. 
 
 Test several kinds of seeds for starch. The best results 
 will be obtained by first grinding seeds into a powder (by 
 means of a mortar) and then preceding as in making starch 
 paste. 
 
 XXVI. Test for Grape Sugar. 
 
 The presence of grape-sugar may be detected as follows : 
 Dissolve a small amount of grape-sugar in a test-tube. Add 
 a few centimeters of Fehling^s solution and boil over gas or 
 alcohol flame. A reddish precipitate will be formed. The 
 formation of this precipitate after the above procedure in- 
 dicates the presence of grape-sugar in' the substance tested. 
 
 XXVIl. Digestion of Starch. 
 
 Starch is a solid. It must, therefore, be changed into a 
 soluble form before the developing plant can use it, or before 
 it can be transferred from one place to another. In other 
 words, it must be digested. When starch is digested it is 
 changed to grape-sugar. The digestion of starch in germi- 
 nating seeds may be demonstrated as follows: 
 
 (a) Grind up in mortar with water several wheat or barley 
 seeds. Pour off milky liquid and test for grape sugar 
 as in XXVI. 
 
 20 
 
(b) Grind up several of the same kind of seeds as in (a) 
 that have germinated far enough for caulicle to be 
 easily seen. Pour off liquid and test for grape sugar. 
 
 XXVIIL Endosperm and Cotyledons After Seedlings 
 Have Become Established. 
 
 In preparation for this study a number of grains of corn 
 and beans should be planted in a box (cigar box) containing, 
 good garden soil. Keep under favorable conditions for ger- 
 mination and growth. 
 
 At intervals of one week after the seedlings have ap- 
 peared pull up one of each kind. Note appearance with re- 
 ference [to amount of endopserm in the corn, and size of 
 cotyledons! in beans. Note also condition of plant as to ex- 
 tent of roots and leaves at time when food supply appears 
 exhausted. 
 
 XXIX. Lifting Power of a Growing Seedling. 
 
 It is important for the seedling in becoming established 
 to push its leaves above the ground. It must do this in order 
 to be ready to make its own food before the food supply 
 stored up in the seed is exhaust- 
 ed. This process often requires 
 considerable force, especially 
 when the surface of the ground 
 is hard. The lifting power of 
 the growing stem may be meas- 
 ured by having it lift a weight. 
 
 One of the plants grov/ing in 
 box prepared in XXVIII may be 
 used. 
 
 As soon as it appears about 
 one inch above the ground ar- 
 range apparatus as shown in Fig. 
 
 12. The larger bottle (a) (about 
 one inch in diameter) should be 
 cut off at bottom and top so as to 
 make a tube of uniform diam- 
 eter. (Make a scratch around 
 
 glass bottle with a file- A quick ^ , 
 
 - , Ml ji 11 1 11 Apparatus for measuring the force 
 
 blow Will then usually break the of the upward growth of the plant. 
 
 21 
 
bottle at the desired place.) A tube made from a large 
 test-tube is easier to prepare. The smaller bottle (b) should 
 fit easily into the tube made from the larger one. 
 
 Put (a) over plant, protecting the plant with small wad 
 of cotton, and insert (b) in (a) as shown in figure* Partly 
 fill (b) with shot. A narrow slip of paper should be pasted 
 vertically on side of (a) and a mark made at the level of the 
 bottom 'of the inner bottle. As the plants grow upward it 
 must lift the weight. A daily record of the height should be 
 indicated by mark on strip of paper. The work done may 
 be estimated in terms of gram-centimeters. (Vertical dis- 
 tance in centimeters times weight of bottle plus shot and cot- 
 ton) , or in terms of pressure reduced to grams per sq. cm. 
 or pounds per square inch i. e. pressure that would be exert- 
 ed if the stem had 1 sq. cm. or one sq. in. cross section. 
 This may be found by the formula: 
 
 Weight 
 
 3.1416 X R2 of stem 
 
 Osterhout found that a plant one-eighth inch in diame- 
 ter exerted a pressure (lifted a weight) of one pound. This 
 is at the rate of 81.5 pounds per square inch, a little greater 
 than the usual pressure in boilers of ordinary stationary en- 
 gines. 
 
 .11 
 
 13. Bean with the 
 stem marked, in 
 order to deter- 
 mine the region of 
 greatest growth. 
 
 After trying this experiment with one 
 plant it should be repeated with others, in- 
 creasing weights each time so as to find the 
 maximum weight that may be lifted. 
 
 XXX. Region of Growth of Stem and Root. 
 
 The pressure exerted by the plant in the 
 previous experiment was a growth-pressure. 
 Where this growth takes place may be 
 shown as follows : 
 
 Carefully remove one of the plants grow- 
 ing in box prepared in XXVIII and by means 
 of a fine thread (a strand of silk is best) 
 which has been dipped in India ink mark 
 stem of plant at regular intervals (2 mm. or 
 1-8 in. ) See Fig. 13. The roots may also be 
 marked in same way. Place roots of plant 
 
 22 
 
between folds of moist cloth or blotting paper. Make daily 
 examinations of plant. Note where growth takes place in 
 stem and roots as indicated by distance between marks, at 
 time of observation, as compared with orignal distance. An 
 illustrated account of this experiment is given in 5, 
 Pp. 25-26. 
 
 XXXL Other Means of Plant Propagation* 
 
 Thus far growth has been considered only with refer- 
 ence to development of the plant from seed. Plants are also 
 propagated in other ways. Whatever the method of pro- 
 pagation (by seed or other means) , one thingjis essential, viz. , 
 a food supply to draw upon while the new plant is developing 
 means (roots and leaves) to shift for itself. 
 
 The following forms of propagation should be studied: 
 
 1. Stem tubers, e. g. potato. 
 
 2. Root tubers, e g. sweet potato. 
 
 3. Crown tubers, e. g. radish. 
 
 4. Bulbs, e. g. onion 
 
 5. Corms, e. g. gladiolus. 
 
 6. Layering, e. g. raspberry. 
 
 7. Leaf cuttings, e. g. begonias. 
 
 8. Stem cuttings, e. g. geraniums. 
 
 9. Hard cuttings e. g. grape. 
 
 10. Grafting. 
 
 11. Budding. 
 
 Suggestions for detailed study for 1, 2, 3, 4, 5, will be 
 found in 2 Pp. 31-35; 6, 7, 8, 9, 10, 11 in 5, Pp. 34-42, exer- 
 cises 17-23; 6 should also be consulted. 
 
 XXXll. Starch and the Green Leaf* 
 
 We have found that the growing plant uses food stored 
 up in the seed, or in leaves, stems, bulbs or corms. After 
 the plant is established, and its food supply exhausted it 
 must make its own food. 
 
 The chief food making organ of the growing plant is the 
 green leaf. The food that it makes is starch. 
 
 The presence of starch in a leaf may be detected as fol- 
 lows : Remove a leaf that has been in sunlight for half a 
 day. Put leaf in boiling water for a few minutes, and then 
 
 23 
 
in alcohol until green coloring matter (chlorophyll) is remov- 
 ed. Test for starch by applying iodine. 
 
 XXXllL Relation of Starch Making to Sunlight. 
 
 We notice that leaves are always held toward the light; 
 generally so that direct sunlight may reach them at some- 
 time during the day. The importance of sunlight may be 
 shown by a simple experiment: Select a leaf that is well ex- 
 posed to sunlight. Shade it by means of black paper for a 
 few days. Remove the shade, and cover portion of the leaf 
 by pinning it between the upper and lower parts of a small 
 paper box (a round pill box will do). The method of fasten- 
 ing illustrated by Fig. 16 is convenient. After two days ex- 
 posure to sunlight remove the leaf and test for starch as in 
 XXV. 
 
 The relation of sunlight to starch making is shown by 
 this experiment to be an important one. Sunlight is neces- 
 sary because it furnished energy to the leaf for this work. 
 
 XXXIV. Composition of Starch. 
 
 In order to investigate further the starch-making pro- 
 cess of the leaf we must get some idea of what starch is 
 composed. 
 
 (a) After drying starch thoroughly, to drive off all the 
 free water, place some in a dry test-tube, and heat 
 over a gas or alcohol flame. In a few moments mois- 
 ture will collect on sides of tube. 
 
 (b) Place some more starch in a test-tube. Insert one 
 end of a short piece of glass tubing, bent at right 
 angles, into a cork. Fit the cork into the test-tube 
 containing starch, making connections air-tight. 
 Heat the starch as in (a) but while heating place free 
 end of glass tube in glass of lime water. The gases 
 that are evolved from the heat will pass into the lime- 
 water. The limewater will become milky, indicat- 
 ing that carbon dioxide has been driven off from the 
 starch. 
 
 These experiments indicate that starch contains, at 
 least, elements found in water and carbon dioxide viz., car- 
 bon, hydrogen and oxygen. More exact analysis would show 
 
 24 
 
that starch is a combination of these elements in the propor- 
 tion of C 6 H 10 0 s. 
 
 XXXV. Absorption of Carbon Dioxide by the Leaf. 
 
 While it does not necessarily follov/ from the experi- 
 ments in XXXV that starch is made from water and carbon 
 dioxide, we are justified 
 in trying to determine 
 whether they are used by 
 the leaf while the starch- 
 making progress is goingon. 
 
 The fact that the leaf uses 
 carbon dioxide may be 
 shown by means of an ex- 
 periment arranged as shown 
 in Fig. 14. 
 
 An empty mason jar is inverted over a lighted candle 
 floating on a cork in a basin of water. When the candle 
 goes out (due to exhaustion of oxygen) it should be with- 
 drawn by means of string (previously attached to it), and a 
 leaf substituted. The jar should not be lifted at any tirn^ 
 above the surface of the water. Another jar for control, but 
 without leaf, should be used in same way as the jar with 
 leaf. The experiment should be set up in the morning on a 
 clear day, and the leaf exposed to sunlight for several ( six) 
 hours. Finally, place a piece of glass over the mouth of the 
 jar containing the leaf. Without admitting any air restore 
 jar to upright position. Introduce a lighted candle. If it 
 does not go out immediately, and no air has been admitted 
 some oxygen must have been set free in the jar during the 
 exposure of the leaf to sunlight. The most probable source 
 of this oxygen is through the decomposition of carbon dioxide 
 (the product of combustion of the candle in the first part of 
 the experiment) by the leaf while in sunlight. 
 
 14. Arrangement for investigating the power 
 of a leaf to “restore” air which has been 
 “vitiated” by a burning candle, (Sec- 
 tional view) , 
 
 25 
 
15. Arrangement for collecting the gas 
 given off by a water-plant in sun- 
 light, 
 
 XXXVL Oxygfcn Given Off by 
 
 Green Plant in Sunlight. 
 
 Thislmay be shown by us- 
 ing some plant that grows sub- 
 merged in water (e. g. horn- 
 wort) and arranging it be- 
 neath a funnel as shown in 
 Fig 15. The funnel is filled by 
 placing it entirely under water 
 and stopping narrow end tight- 
 ly with small cork. If a plate 
 of glass is held closely over 
 the broad end, the funnel filled 
 with water may then be re- 
 moved to battery jar, and set 
 up as indicated in the figure. 
 Place in sunlight. 
 
 When the neck of the fun- 
 nel is filled with gas remove 
 cork and insert glowing 
 splinter. If the glow be- 
 comes brighter or bursts into 
 flame, it indicates that the gas 
 is rich in oxgyen. If the ap- 
 paratus is kept in the shade no 
 oxygen will be evolved. 
 
 XXX YII. The Amount of Oxygen Given Off by the Plant 
 Depends Upon Amount of Carbon Dioxide Absorbed. 
 
 We infer from XXXV that carbon dioixde is used by the 
 green leaf. We make this inference because the only appar- 
 ent source of the oxygen in the jar is from decomposition of 
 the carbon dioxide. Since there is no oxygen in the control 
 jar, this decomposition must be through action"of the leaf. 
 
 In order to be sure that the oxygen given off by the 
 plant depends upon the carbon dioxide we may make a 
 further test : 
 
 This test depends upon the fact that fresh spring or 
 
 26 
 
well water usually contains an abundance of carbon dioxide 
 and also that the presence of carbon dioxide may be detected 
 by use of limewater. 
 
 Put some aquatic plants (hornwort or algae) into three 
 glasses or jars: (a) filled wityspring or well water that has 
 been standing overnight; (b) filled with fresh spring or well 
 water. (To make the results more certain carbon dioxide 
 may be introduced by blowing the breath into the water by 
 means of a glass tube); (c) filled with distilled water (water 
 boiled and cooled will do). Set glasses in sunlight. Within 
 an hour a few gas bubbles will be seen coming from the 
 plant in (a); many gas bubbles in (b); no gas bubbles in (c). 
 Test the water in the three glasses for carbon dioxide by 
 means of a few drops of lime water; (a) will show a trace of 
 carbon dioxide; (b) will give a decided test; (c) will show 
 none. 
 
 By means of glass tube blow the breath into the water 
 of (a) and( (c. Set glasses in sunlight and note increase of 
 gas bubbles given off by the plants. Here w’e see a close 
 relation between the amount of carbon dioxide and the evo- 
 lution of oxygen by the plant. More elaborate experiments 
 than can be described here have shown that carbon dioxide 
 is broken up, that carbon is retained in the plant, and that 
 oxygen is given off. The source of carbon in the starch made 
 by the plant is carbon dioxide. 
 
 XXXVIIL Transphation. 
 
 Starch also contains hydrogen and oxygen. We know 
 that water is composed of these elements, and also that 
 water is necessary for the plant to grow. 
 
 We cannot prove by a simple experiment 
 that water is actually used by the green leaf 
 in starch-making but we can show that water 
 passes through the leaf, and is thus available 
 for such use. The passage of water through 
 the leaf into the air is called transpiration. 
 
 Without removing leaf from the plant 
 arrange on opposite sides of leaf, by means 
 
 of bent wire, two watch crystals (two pieces Arrangement for 
 
 of glass will do) as indicated in Fig 16. Seal determining wheth- 
 the edges of the crystals with vaseline. In a vaporf""^* offwater 
 
 27 
 
short time, especially if the glasses are cool, vapor of water 
 will be condensed on the sides of the glasses next to the leaf. 
 Observe the side of the leaf giving off the more moisture. 
 
 Another method for showing that the leaves give off 
 moisture is given in 5, P. 23. 
 
 XXXIX. Determination of Amount of Transpiration. 
 
 The amount of water given off by a leaf may be meas- 
 ured as follows: Arrange apparatus as illustrated in Fig. 
 17. The bottle should be filled v/ith water, and the cork 
 containing leaf and bent tube forced down until the water 
 
 17. Apparatus for measuring the transpiration of a leaf and 
 the degree in which it is affected by sunlight, wind, 
 rolling the leaf. etc. 
 
 passes into the horizontal tube nearly to the second bottle. 
 As soon as apparatus is set up, mark the end of the hori- 
 zontal column of water. As transpriation goes on water in 
 he tube will move toward the bottle holding the leaf. After 
 one-half hour measure the distance through which column 
 of water has traveled. 
 
 If diameter of tube is known, the amount of transpiration 
 of a leaf in a given time may be calculated (area of cross 
 section of tube times length of water column). Dividing the 
 amount thus obtained by square inches of surface of leaf 
 will give the amount of transpiration per square inch. 
 
 There are many problems that may be solved by means 
 of this simple apparatus, e. g. rates of transpiration of 
 
 28 
 
leaves of different kinds of plants; difference in transpira- 
 tion between old and young leaves; estimation of total 
 amount of transpiration of an entire plant; effect of sunlight 
 on rate of transpiration; devices in transpiration, such as 
 hairy covering of leaf, etc. 
 
 XL* Path of Water in the Stem of a Plant. 
 
 Water must reach the leaf by way of stem. What path 
 does it take? 
 
 Cut off a leafy branch of a plant (geranium), and place 
 cut end in solution of eosin (5 Pp. 23 24). After an hour or 
 more cut the stem a short distance above the lower end. 
 
 The path of water as indicated by red stain will be seen 
 in Ithe fibrous portion of the stem (fibro-vascular bundles). 
 A closer examination will show that the central portion of 
 each bundle is stained more deeply than the rest. 
 
 Let the branch stand in the fluid until the leaves begin 
 to be colored. By making successive cuts in stem toward 
 the leaves, the path of water will be found to extend from 
 the fibrous bundlesnnto the^veins of the leaf. The veins are 
 smaller extensions of the bundles of the stem. 
 
 XLl. Path of Starch. 
 
 Since the leaves make starch v/hich must be digested 
 and carried to the lower parts of the plant we would expect 
 to find provision Jnade for its transference. What then is 
 the path of the starch? 
 
 We found in XXXI that some plants could be propa- 
 gated by means of hard cuttings. Such plants have sufficient 
 food supply stored up in the stem to supply the plant while 
 it is getting a start. 
 
 In some plants like the willow this food supply is largely 
 starch. If v/e make a short willow cutting about six inches 
 long and girdle it just above the lowest bud we will divide 
 the food supply into unequal parts, thus limiting the avail- 
 able means for passage ofjfood to the central or woody part. 
 (The cutting is girdled by removing a ring of bark about 
 one-half inch wide, laying bare the wood). Place the girdled 
 cutting in a mason jar filled v/ith water. In a short time it 
 will start to grow. If the food supply including starch is 
 
 29 
 
carried through the layer of bark the growth will be unequal 
 because '"the food supply in the parts above and below the 
 girdle are funequal. If there is an equal growth above and 
 below the girdle the food must And a passage in the w^oody 
 portion of the stem. A similar cutting which has not been 
 girdled should be placed in another jar as a control experi- 
 ment. 
 
 ‘‘Ringing grape vines is practiced by many growers to 
 secure earlier maturity and larger bunches of grapes. A 
 ring of bark is removed from the bearing arm between the 
 main vine and the buds which are to produce the fruit of 
 the season. This does not interfere with the ascent of the 
 sap, which passes through the outer ring of undisturbed 
 wood; but it does prevent the return of the food which has 
 been formed from the sap in the leaves. Thus parts of the 
 branch above the ring can draw upon all the food formed in 
 the leaves of that branch, none of it passing on to build up 
 the parent vine. Consequently the over fed bunches grow 
 faster and become larger than their less favored mates; but 
 the vine itself may suffer, and size may be added and early 
 maturity produced at the expense of quality.” * 
 
 XLIL Region of Growth in Woody Stems, 
 
 By slipping the bark from a woody stem (especially in 
 spring time) a thin layer of juicy, mucilaginous substance 
 wil be seen. This is the cambium or growing region of 
 the stem. 
 
 For further explanation of the cambium see 2, P. 257. 
 
 In the foregoing exercises very little attention is given 
 to the root. For experimental studies of plant growth in 
 which the root is concerned, consult 7. 
 
 * Bui. 151, New York Agricultural Experiment Station, Geneva, New 
 York. 
 
 30 
 
References. 
 
 1. Experiments with Plants. By W. J. V. Osterhout, pp 51 1. New 
 
 York: Macmillan Co. |i«25 
 
 2. Botany, an Elementary Text-book. By E. H. Bailey, pp 377. 
 
 New York: Macmillan Co. __J 5 i.io 
 
 3. Conditions Necessary for Plants to Grow Well. Columbus, Ohio, 
 
 Agricultural College, Extension Bui. Vol. I, No. 8 Free. 
 
 4. Improvement of the Corn Crop. Columbus, Ohio, Agricultural 
 
 College, Extension Bui. Vol. II, No. 7 Free. 
 
 5. Plant Production, Exercises in Elementary Agriculture. By D. 
 
 J. Crosby, Washington, D. C., U. S. Department of Agri- 
 culture, Office of Experiment Stations, Bui. No. 186. Free. 
 
 6. The Propagation of Plants. By E. C. Corbett, Washington, D. 
 
 C., U. S. Department of Agriculture. Farmers’ Bulletin 
 No. 157. 
 
 7. The Soil and its Relation to Plants. By B. M. Davis, Oxford, O., 
 
 Miami University, Bui. No. 3, Ser. VI. Free. 
 
 31 
 
Material and Apparatus With Estimated Cost. 
 
 1. Alcohol, I pt. $ .50 
 
 2. Alcohol lamp, 4 oz .20 
 
 3. Balance, Chaslyn (1906) model 15.C0 
 
 4. Balance, spring .15 
 
 5. Bottles, 4 or 6 oz,, wide month, with corks, i doz .50 
 
 6. Bottles, 3 dr. homo-vials, with corks, 3 doz,. .30 
 
 7. Boxes, empty cigar and chalk boxes 
 
 8. Candles, Paraffine, 2 .05 
 
 9= Clamps, wooden clothes pins with spring, i doz .10 
 
 10. Cotton, I roll .10 
 
 11. Fehling’s solution, 4 oz .25 
 
 12. Filter paper, in sheets, i quire .35 
 
 13. Funnel, glass, 5 in .20 
 
 14. Fruit press, (fig. ii) .25 
 
 15. Glass tubing, assorted sizes, yi lb .20 
 
 16. Grape sugar (glucose) X lb .05 
 
 17. Graduate, cylinder, 50 ccm, capacity .35 
 
 18. Iodine, tincture, i oz .15 
 
 19. Jars, Mason, i doz. each of pts. and qts i.oo 
 
 20. Jars, battery, i gal., 2 .70 
 
 21. Lime, small quantity 
 
 22. Lye, concentrated, i can .10 
 
 23. Mortar and pestle, 4 in., glass .25 
 
 24. Seeds, a good supply, including corn, beans, peas, pumpkin, 
 
 radish, castor-bean, sweet-pea, walnut, peach, etc .50 
 
 25. Stoppers, rubber. No. 7, 4 with i hole and 4 with 2 holes i.oo 
 
 26. Test-tubes, 5 in., i doz. .20 
 
 27. Thermometers, chemical, 2 i.oo 
 
 28. Tumblers, common glass, i doz. .30 
 
 29. Vaseline, small bottle .05 
 
 30. Watch glasses, small, X .10 
 
 31. Weights, metric, i set (i centigr. to 20 gr.) .55 
 
 Notk — N os. 2, 12, 13, 15, 17, 20, 23, 25, 26, 27, 30, 31 may be obtained 
 from the Columbia School Supply Co., Indianapolis, Ind.; 3 from C. H. 
 Stoelting Co., 31-45 W. Randolph St., Chicago, 111 .; i, 5, 6, ii, 16, 18, 28 at 
 any drug store; the rest at a general merchandise store. If the Chaslyn 
 balance (3) is bought it will not be necessary to buy a set of metric 
 weights (31). 
 
 32