Class Book. 1TB 3 a 3 | JA: Copyright^ . COPYRIGHT DEPOSIT. Digitized by the Internet Archive in 2011 with funding from The Library of Congress http://www.archive.org/details/schoolhouseitsheOOmoor THE SCHOOL HOUSE Its Heating and Ventilation BY JOSEPH A. MOORE INSPECTOR OF PUBLIC BUILDINGS STATE OF MASSACHUSETTS !9 5 LIBRARY of CONGRESS Two Copies Received NOV 25 1905 Copyright Entry CIASS O. XXc. No. COPY B. Copyrighted, 1905 Bv Joseph A. Moore Published by the Author Boston, Mass. GRIFFITH -STILLINGS PRESS 368 CONGRESS ST.- BOSTON INTRODUCTION The writer having been for the last eighteen years engaged in the inspection of public buildings in Massachusetts, and in super- vising the construction of and testing the various methods of heat- ing and ventilation, especially in schoolhouses, presents to those interested in our public schools some suggestions as to the construc- tion and the heating and ventilation of such buildings. The class of buildings selected are those of small or moderate size, of which many are erected each year. It is not the writer's intention to give theoretical or scientific descriptions or arguments, but simply such methods and plans as have been proved by actual experience to give satisfactory results. Many of the plans were designed by the writer for the annual official reports of the late Rufus R. Wade, Chief of the Massachu- setts District Police The method of setting up indirect radiators, as shown in the plans and now generally adopted in Massachusetts, was designed by the writer, and first published in drawings which formed part of the official exhibit of the Inspection Department of the Massachu- setts District Police at the Columbian Exposition at Chicago in 1S93, and for which an award was given. Other plans formed part of the exhibit at the Paris Exposition in 1900, for which an award was also given, and at the Louisiana Purchase Exposition at St. Louis in 1904, for which a gold medal was also awarded the department. Boston, Mass. 1905. CONTENTS. PART I. Chapter I — The schoolhouse, location, size and cost, building committee, plans, Massachusetts laws, appropriation, choice of site, height, construction, prevention of spread of fire, means to extinguish fire, basement, corridors, vestibules, exits, stairways, fire escapes, doors, windows, class rooms, seating, blackboards, clocks, thermometers, pictures and plaster casts, telephones and fire-alarm boxes. Chapter II — Air, composition, impurities, respiration, products of respiration, amount of air required, humidity, lights, test- ing purity of air, Wolpert's test, preparation of lime water, measurement of air, wind velocity and pressure. Chapter III — i\mount of air required by Massachusetts regula- tions, some erroneous ideas of ventilation, circulation of air, u systems," location of inlets and outlets, exhaust and plenum methods, leakage, velocity, beams and projections below ceil- ing, ceiling ventilation in halls, location of heating apparatus, deflectors, mixing clampers, dampers in vent flues, flap valves, force and direction of prevailing winds, adjustable switch dampers, location of discharge from vent flues, back draft, caps on vent flues, testing movement of air currents. Chapter IV" — Tests of amount of air supply and heat in school- rooms, difference in cost of heating schoolhouses, size and construction of warm air ducts and flues, wire grills, cast-iron registers, mixing dampers, adjusting dampers, aspirating chimneys and vent flues, heat in vent flues, location of vent flue heaters, exhaust fans, amount of steam heat in vent flues, size and location of vent openings, chimneys, location, height and area. Chapter V — Boilers, horse-power, grate surface, heating surface, determining size of boiler, shell, heads, tubes, braces, fittings and appliances, standard sizes, setting smoke flues, U.S. Government rule for safe pressure, Massachusetts inspectors' rule, water-tube boilers, upright, tubular, sectional cast-iron, Massachusetts inspectors' requirements for fittings, Massachu- vi CONTENTS. setts law for licensing of engineers and firemen and for the inspection of steam boilers. Chapter VI — Steam-pipes, size, covering, valves, locating pipes, radiators, quantity, location, casing radiators, rule for calcu- lating amount of indirect radiation, automatic heat control. Chapter VII — Furnaces, use in small buildings, location, con- struction, size, wrought and cast-iron, test for gas leakage, brick setting, portable type, smoke-pipes, pit, air supply and mixing valves, location as to air supply, cold air rooms, com- bination of furnace and steam heating, twin connected furnaces, combination of furnace and hot water heating, fans for supply- ing air to furnaces, electric motors, gas engines, water-motors. Chapter VIII — Janitors, duties and instructions for care and management of heating and ventilating appliances in school- houses. Chapter IX — Sanitary appliances in schoolhouses, outside sani- tary buildings. PART II. Plate I — Plan and description of one-room schoolhouse, showing method of heating and ventilating. Plates II and III — Plan, sections and description of one-room portable schoolhouse, showing heating, ventilating apparatus and circulation of air. Plates IV, V and VI — Plans and description of two-room, one- story schoolhouse, with sections of heating and ventilating -apparatus and circulation of air. Plates VII, VIII, and IX — Plans and description of two-room, two-story schoolhouse, and section through ventilating shaft. Plates X, XI, XII, XIII and XIV — Plans and description of four- room, two-story schoolhouse, showing fan and furnace and sections through warm air and vent flues. Plates XV, XVI and XVII — Plans and description of five-room two-story schoolhouse, steam heated. Plates XVIII, XIX and XX — Plans and description of six-room, two-story schoolhouse, with combination of furnace and steam heating. Plates XXI, XXII, XXIII and XXIV— Plans and description of seven-room, two-story grammar schoolhouse, with sections of steam heating and ventilating apparatus. CONTENTS. vii Plates XXV, XXVI, XXVII and XXVIII — Plans and descrip- tion of eight-room, two-story schoolhouse, showing steam heating by combination of a fan and a gravity air supply. Plates XXIX, XXX, XXXI and XXXII— Plans and description of an eight-room, two-story school, steam heated. Plates XXXIII, XXXIV and XXXV— Plans and description of small two-story high school, steam heated. Plates XXXVI and XXXVII— Plans for sanitary buildings. Plate XXXVIII — Plan, section and description of a direct-indirect (steam) radiator. Plate XXXIX — Plan, section and description of portable furnace setting for small hall or church. Plate XL — Section and description of foot- warmer for school- house corridor. Plate XLI — Setting for one horizontal tubular boiler. Plates XLII and XLIII — Sections of setting for one horizontal tubular boiler. Plate XLIV — Section of setting for two horizontal tubular boilers. Figures. Numbers 1 to 9. — Schoolhouse furniture. 10 — Prof. Wolpert's air tester. 11 — Lime water apparatus. 12 — Template for correcting anemometer blades. 13 — Form of air inlet in schoolroom. 14 — Form of air inlet in schoolroom. J 5, 16, 17 and 18 — Position of anemometer in measuring air. 19, 20 and 21 — Location of inlets and outlets and cir- culation of air in schoolrooms. Tables. 1 — For Wolpert's air test. 2 — Of wind velocity and pressure. 3 — Of tests of amount of heat and air in schoolhouses. 4 — Of tests of amount of heat and air in schoolhouses. 5 — Of tests of amount of heat and air in schoolhouses. 6 — Of tests of amount of heat and air in schoolhouses. viii CONTENTS. 7 — Relative cost of fuel in schoolhouses. 8 — Of boiler, grate and heating surfaces. 9 — Of area of grate surface and tube opening. 10 — Of standard boiler tubes. 11 — Of standard sizes of boilers. 12 — Of dimensions of brick settings for boilers. 13 — Of dimensions of brick settings for boilers. 14 — Of sizes of supply and return steam-pipes. 15 — Of areas of rectangular openings. 16 — Of areas and circumference of circles. 17 — For equalizing diameter of pipes. 18 — Of number of gallons in round tanks. 19 — Of capacity of pipes and registers. 20 — Of weight of steel bars per foot. 21 — Of standard gauges. 22 — Of weights of galvanized sheets. 23 — Of circumferences of circles used by boiler makers. 24 — Of number of tubes used in return tubular boilers. 25 — Of dimensions of standard wrought-iron pipe. 26 — Of expansion of metals. 27 — For estimating size of coal bins. CHAPTER I. THE SCHOOL HOUSE. WHEN it becomes desirable for a city or town to erect a new schoolhouse, some of the first questions to be decided are : Where shall it be located, and what is to be the size and cost ? The first question, as to location, is usually decided by deter- mining where is the most convenient place that will best accom- modate the greater part of the pupils in the school district. The size, by the number of pupils to be provided for, and the cost, by the ability or disposition of the city or town to appropriate the requisite amount of money for that purpose. The choice of location is often a matter of considerable con- troversy, and it sometimes, unfortunately, depends upon the power or local strength of the contending parties. It should, however, be determined which location will best serve the interests of the greater number of pupils, and should be where it will be free from the objections of noise or unfavorable surroundings. A site near large manufacturing establishments, or where objectionable noises, gases or odors are produced, should be avoided, also one where unhealthy conditions may exist. A dry and healthy location should be selected in preference to one that is low and wet, or on filled ground. The size of the building should be determined by the number of pupils to be provided for in the district in which the building is to be located. Not only the present needs of the district should be considered, but also the probable increase in the near future. The cost and character of the building will depend consider- ably upon the financial ability of the city or town. It is not true economy to attempt to build too large a building for too little money, or to reduce the cost to such a degree as will necessitate the omission of certain essential requisites for a good building. Where this is done, dissatisfaction will be the result when the building is completed. Erecting a large and poorly-constructed building for the sake of obtaining a large building at a low cost will in the future prove 2 THE SCHOOL HOUSE. more expensive and unsatisfactory than if a smaller but well-con- structed one is built, and the committee having charge of the work will eventually receive more blame than thanks for their work. When a city or town decides to erect a new schoolhouse, it is advisable that a committee be appointed and authorized to procure plans, specifications and bona fide estimates of the cost. Where possible, the committee should consist of one or more practical business men and builders, and also one or more repre- sentatives of the school board. It is not advisable to appoint too large a committee, as is some- times the case. With a large committee the actual work is usually done by a few members, and discussions often arise which delay the construction. A committee of three or five members will often make better progress and give better satisfaction than one that is too large. After the committee has been appointed it is advisable for them to invite a limited number of architects who have had experience in schoolhouse construction, to submit competitive plans. The invitation should contain a brief description of what is desired ; the number and kind of rooms, height and material of which the build- ing is to be constructed, whether of brick, stone or wood, the location, and also such special features as may be desired. The plans submitted should show the system and method of heating and ventilation. Where this is not done it is sometimes found that a suitable system cannot be installed without making changes in the building plans. The Massachusetts law requires the plans and specifications for schoolhouses to be filed with the State "Inspector of Factories and Public Buildings" of the district in which the building is located before the building is constructed, and is as follows : Chafter 104, Revised La-vus, Massachusetts {igo2~). OF THE INSPECTION OF BUILDINGS. * ******** Specific Requirements. Section 22. No building which is designed to be used, in whole or in part, as a public building, public or private institution, schoolhouse, church, theatre, public hall, place of assemblage or place of public resort, and no building more than two stories in height, which is designed to be used above the second story, in whole or in part, as a factory, workshop or mercantile or other establishment and has accommodations for ten or more employees above said story, and no building more than two stories in height THE SCHOOL HOUSE. 8 designed to be used above the second story, in whole or in part, as a hotel, family hotel, apartment house, boarding house, lodging house or tenement house, and has ten or more rooms above said story, shall be erected until a copy of the plans thereof has been deposited with the inspector of factories and public buildings for the district in which it is to be erected by the person causing its erection, or by the architect thereof. Such plans shall include the method of ventilation provided therefor and a copy of such portion of the specifications therefor as the inspector may require. Such building shall not be so erected without sufficient egresses and other means of escape from fire, properly located and constructed. The certificate of the inspector, indorsed with the approval of the chief of the district police, shall be conclusive evidence of a compliance with the provisions of this chapter unless, after it is granted, a change is made in the plans or specifications of such egresses and means of escape without a new certificate therefor. Such inspector mav require that proper fire stops shall be provided in the floors, walls and parti' ions of such building, and may make such further requirements as may be necessary or proper to prevent the spread of fire therein or its communication from any steam boiler or heating apparatus. Section 23. No wooden flue or air duct for heating or ventilating purposes shall be placed in any building which is subject to the provisions of sections twenty-four and twenty-five and no pipe for conveying hot air or steam in such building shall be placed or remain within one inch of any woodwork, unless protected to the satisfaction of said inspector by suitable guards or casings of incombustible material. Section 24. Whoever erects or constructs a building, or an architect or other person who draws plans or specifications or superintends the erection or construction of a building, in violation of the provisions of this chapter, shall be punished by a fine of not less than fifty nor more than one thousand dollars. Sectiov 25. A building which is used, in whole or in part, as a public building, public or private institution, school house, church, theatre, public hall, place of assemblage or place of public resort, and a building in which ten or more persons are employed above the second story in a factory, work- shop, mercantile and other establishment, and a hotel, family hotel, apart- ment house, boarding house, lodging house or tenement house in which ten or more persons lodge or reside above the second story, and a factory, workshop, mercantile or other establishment the owner, lessee or occupant of which is notified in writing by an inspector of factories and public build- ings that the provisions of this chapter are deemed by him applicable thereto shall be provided with proper egresses or other means of escape from fire, sufficient for the use of all persons accommodated, assembled, emploved, lodged or resident therein ; but no owner, lessee or occupant of such building shall be deemed to have violated this provision unless he has been notified in writing by such inspector what additional egresses or means of escape from fire are necessary and has neglected or refused to supply the same. The egresses and means of escape shall be kept unobstructed, in good repair and ready for use. Stairways on the outside of the building shall have suitable railed landings at each story above the first, accessible at each storv from doors or windows, and such landings, doors and windows shall be kept clear of ice, snow and other obstructions. Portable seats shall not be 4 THE SCHOOL HOUSE. allowed in the aisles or passageways of such buildings during any service or entertainment held therein. If the inspector so directs in writing, women or children shall not be employed in a factory, workshop, mercantile or other establishment, in a room above the second story from which there is only one egress, and all doors and windows in any building which is subject to the provisions of this section shall open outwardly, and every room above the second story in any such building, in which ten or more persons are employed, shall be provided with more than one egress by stairways or by such other way or device, approved in writing by the inspector, as the owner may elect, on the inside or outside of the building, placed as near as practi- cable at each end of the room. The certificate of the inspector shall be conclusive evidence of a compliance with such requirements. Section 26. Each story above the second story of a building which is subject to the provisions of the preceding section shall be supplied with means of extinguishing fire, consisting of pails of water or other portable apparatus or of a hose attached to a suitable water supply and capable of reaching any part of such story; and such appliances shall be kept at all times ready for use and in good condition. ********* Section 36. The audience hall in a-building which is erected or designed to be used in whole or in part as a theatre or in which any change or altera- tion shall be made for the purpose of using it as a theatre shall not be placed above the second floor of said building. The audience hall and each gallery of every such building shall, respectively, have at least two independent exits, as far apart as may be, and if the audience hall is on the second floor, the stairways from said floor to the ground floor shall be enclosed with fire- proof walls from the basement floor up, and shall have no connection with the basement or first floor of the building. Every such exit shall have a width of at least twenty inches for every one hundred persons which such hall, or gallery from which it leads, is capable of holding; but two or more exits of the same aggregate width may be substituted for either of the two required exits. None of the required exits shall be less than five feet wide. Section 37. The proscenium or curtain opening of all theatres shall have a fire resisting curtain of an incombustible material, properly constructed and operated by proper mechanism. The certificate of the inspector of factories and public buildings shall be conclusive evidence of a compliance with such requirements. ********* Section 44 If, in the erection of an iron or steel framed building the spaces between the girders or floor beams of any floor are not filled or covered by the permanent construction of said floors before another story is added to the building, a close plank flooring shall be placed and maintained over such spaces, from the time when the beams or girders are placed in position until said permanent construction is applied; but openings, pro- tected by a strong hand railing not less than four feet high, may be left through said floors for the passage of workmen or material. Section 45. In the construction of any iron or steel framed building having a clear story of twenty-five feet elevation or more, a staging with a close plank flooring shall be placed under the whole extent of the beams, girders or trusses of such story upon which iron or steel workers are THE SCHOOL HOUSE. 5 working, and not more than ten feet below the under side of such beams girders and trusses. Section 46. Inspectors of factories and public buildings shall enforce the provisions of the two preceding sections, and whoever violates any provision thereof shall be punished by a fine of not less than fifty nor more than five hundred dollars for each offence. Section 51. The supreme judicial court or the superior court shall have jurisdiction in equity, upon the petition of an inspector, temporarily o r permanently to restrain the erection, construction, use or occupation of a building in violation of the provisions of this chapter. Section 52. The supreme judicial court or the superior court shall have jurisdiction in equity to restrain the illegal placing, maintenance or use of any building, structure or other thing. It may, upon the petition of a city or town, by its attorney, for such relief, require the removal of any such building, structure or other thing by the owner, and may authorize the city or town, in default of such removal by the owner, to remove it at his expense. The provisions of this section shall apply to such buildings, structures or other things so placed which were maintained or used prior to, as well as after, the second day of May in the year eighteen hundred and ninety-nine. Upon such petition, the defendant shall be presumed to have acted without a license or authority until he proves to the contrary. Section 53. Sections fifteen to eighteen, inclusive, twenty-two to twenty- six, inclusive, thirty, thirty-one, thirty-six, thirty-seven, forty-eight to fifty- one, inclusive, and fifty-four shall not apply to the city of Boston. Section 5-1. Cities may by ordinance provide that the provisions of sections fifteen to eighteen, inclusive, twenty -two to twenty-six, inclusive, thirty-six, thirty-seven, forty-eight and forty-nine shall apply to any building of three or more stories in height within their respective limits. Section 55. Whoever, being the owner, lessee or occupant of any building or room described in section twenty-two violates the provisions of sections fifteen to eighteen, inclusive, twenty-two to twenty-six, inclusive, thirty-six, thirty-seven, forty-eight and forty-nine, shall be punished by a fine of not less than fifty nor more than one thousand dollars. Section 5(5. Whoever violates any provision of this chapter for Avhich no other penalty is specifically prescribed shall be punished by a fine of not more than one hundred dollars. Chapter 106, Revised La-ws, Massachusetts. Sanitary Provisions. ********* Section 54. Every public building and every school house shall be kept clean and free from effluvia arising from any drain, privy or nuisance, shall be provided with a sufficient number of proper water closets, earth closets, or privies, and shall be ventilated in such a manner that the air shall not become so impure as to be injurious to health. The provisions of this section shall be enforced by the inspection department of the district police. Section 55. If it appears to an inspector of factories and public buildings that further or different sanitary or ventilating provisions which can be pro" 6 THE SCHOOL HOUSE. vided without unreasonable expense, are required in any public building or school house, he may issue a written order to the proper person or authority, directing such sanitary or ventilating provisions to be provided. A school committee, public officer or person who has charge of, owns or leases any such public building or school house who neglects for four weeks to comply with the order of such inspector shall be punished by a fine of not more than one hundred dollars. Whoever is aggrieved by the order of an inspector issued as above provided and relating to a public building or school house may, within thirty days after the date of the service thereof, apply in writing to the board of health of the city or town to set aside or amend the order ; and thereupon, the board, after notice to all parties interested, shall give a hearing upon such order, and may alter, annul or affirm it. After the committee have decided upon the plan preferred, they can then report to the city or town and ask for an appropriation sufficient to properly construct the building. The appropriation should be sufficient to cover the entire cost of the site, building, furnishing, grading and the architect's fee, also a reasonable allowance for contingencies. By this method addi- tional appropriations are avoided, and the committee and architect are not obliged to revise the plans and omit essential things in order to keep within the appropriation. The appropriation having been made, the committee should be authorized to contract for the building. If architects, before making the finished drawings, or committees, before accepting them, would (in Massachusetts) submit them to the State Inspector for the district, the inspector will inform them as to whether or not the plans meet the requirements of law and will be approved. Sometimes a committee will accept plans that the inspector can- not approve, and changes will be ordered which may increase the cost after the appropriation is made, or will allow the contractor to present a bill for " extras." " Be sure you are right and then go ahead." In deciding upon competitive plans committees are often pleased with a well-drawn and colored elevation or perspective, and some- times lose sight of the more important interior arrangement of the rooms, etc. Site. In deciding upon the choice of a site for a schoolhouse many different questions will arise : as to where it should be located to be near the central part of the district, the cost of the land, the nature of the soil, and the objectionable surroundings to be avoided. THE SCHOOL HOUSE. 7 F A site on high, dry land where a good foundation and good drainage or sewerage can be had should be selected if possible. If low or filled land must be used, care should be taken that good foundations are provided and supported by well-driven piling, if necessary ; also that the walls and bottom of the basement are well protected and made water-tight by asphalt or hydraulic cement. If the schoolhouse is to be built on clav or on land containing springs of water, proper precautions should be taken to provide suitable drainage by a trench outside, filled with small stones, or by drain-tile placed outside to carry off the water. When any doubt exists as to the nature of die ground it is advis- able that borings be made to determine whether there are quick- sands, springs, or unstable places, also as to whether ledges are to be found in excavating. By doing this the architect and con- tractors will be enabled to make a better estimate of the cost, and bills for " extras " are often avoided. A site should be selected where a good light can be had on all sides of the building, and unobstructed by trees or high buildings. High buildings or trees close to a schoolhouse often prove serious ob- stacles to good ventilation on account of deflection of the wind, which sometimes causes reversed drafts in chimneys and ventilating flues. It is not desirable to place the schoolhouse where it is much exposed to very high winds. The building should be set well back from the street and ample yard room provided. Close proximity to manufacturing establishments, where much smoke or noxious gases are produced, should be carefully avoided, as well as a noisy location, where pupils and teachers are annoyed and their attention diverted from school work. The Building. School buildings should be plain, and substantially built. The money frequently expended in the construction of towers, cupolas, and other ornamentation, can be used to much better advantage in substantial construction and convenient interior arrangements. Not that a building should be hideously plain ; but a well proportioned building, with simple and inexpensive ornamentation, can easily be designed by an experienced architect. A schoolhouse, two stories in height, and, in large buildings, with an assembly hall above the second story, is to be preferred to one of three or four stories. 8 THE SCHOOL HOUSE. In case of fire or panic the danger is greatly increased in high buildings. Climbing many nights of stairs, especially for girls, is not recommended. In cities where land is very valuable it sometimes becomes necessary to have the school building more than two stories high ; but where land can be obtained at a reasonable price two stories are preferable. Construction. When a sufficient appropriation can be obtained it is preferable that the building be of fire-proof, or at least, slow-burning construction. After the first cost the expenditure for repairs is much less for brick than for "wooden buildings. If wooden construction is adopted on account of the first cost, care should be taken that the material is of good quality, the timber of sufficient size, and the boarding well protected with a covering of the best quality of building paper. A loosely-constructed building requires in cold weather a constant additional expenditure for fuel to maintain a comfortable temperature in the schoolrooms. This additional expense can be considerably reduced by good construction in the first place. Particular attention should be given to have all trusses properly designed, placed, and of sufficient strength. The writer has found more well-founded complaints of insuffi- cient trussing and defective roof-framing than from any other cause (exclusive of heating and ventilation) in schoolhouse construction. It is too often the case that architects are obliged to cut down the thickness of walls and partitions and reduce the size and quality of the timber because a building committee insists on having a large building for little money. This is false economy, as will be apparent after the building is occupied. Better reduce the size of the building than cut down the material. In brick schoolhouses an air space in the walls is advisable, and the inner walls should be of hard-burned brick with terra-cotta set to receive nailing for the finish. The wood finish should be reduced to the minimum, and the walls smooth plastered. In the better class of buildings Windsor or equally good cement can be advantageously used for door and window trims. Dados of gauged mortar and wood base are also used. THE SCHOOL HOUSE. 9 Oak or ash finish is preferable to white pine or whitewood, which are too soft and easily defaced. Cypress is sometimes used, and in the cheapest buildings Southern pine is frequently used. Expanded metal is much better than wooden lathing. Stamped metal ceilings are sometimes used, but the advantage is not great when the extra cost is taken into account. In some cases in brick school buildings the wood finish in the corridors is omitted and faced brick, carefully laid, and painted with a light-colored gloss paint, is substituted. This has proved quite satisfactory. The upper floor-boards should be of rift Georgia or Florida pine, or of maple, and not over four inches wide. Between the upper and lower floor-boarding should be laid asbestos or other fire resisting paper or material. Means to Prevent Spread of Fire. The following are the requirements of the Massachusetts State Inspectors for buildings other than in the city of Boston : General Specifications for Means of preventing Spread op Fire in Buildings, under the Requirements of Chapter 104 of the Revised Lazvs, as directed by the State Inspectors of Factories and Public Buildings. Special Provi- sions against Spread of Fire, required in Theatres, are not included in those Specif cations. 1. All elevator wells and light shafts, unless built of brick, must be filled in flush between the wooden studs with fire-proof materials and lined with metal or plastered on metallic lathing, as may be directed by the inspector, and all wood-work inside of such wells or shafts, be lined with tin plate, lock-jointed. 2. Where floor beams rest on partition caps or on girders, wall girts, or on wooden sills, fill in between such beams, from the caps, girders, girts or sills, to four inchesabove the plaster ground solid with brick and mortar or other fire-proof material. 3. When floor beams in frame buildings rest on ledger boards, fire-stop thoroughly at each floor with brick and mortar resting on bridging pieces cut in between the studs, or, where practicable, on the ends of lining floor. 4. In brick buildings the space between the furrings on the outside walls or on brick partitions should be filled flush with mortar for a space of five inches in width above and below the floor beams of each story. 5. Where basement or other flights of stairs are enclosed by partitions of brick or wood, the spaces between the studs or wall furrings must be so fire- stopped with brick or mortar as to effectually prevent any fire from passing up between such studs or furrings back of the stair stringers. 6. The soffits of all such enclosed stairs, and also partitions on stairway side, must be plastered on metal lathing. 7. Where a building is occupied above the first floor for any purpose which renders it subject to the provisions of section 22 of chapter 104 of the 10 THE SCHOOL HOUSE. Revised Laws, and the lower story is occupied for stores, or other purposes not connected with the upper floors, the stairways leading to such upper floors must be enclosed with brick walls or with wooden partitions filled solid with brick laid in mortar, or other fire-proof material, and plastered on both sides on metallic lathing, and all doors in such partitions lined with tin plate, lock-jointed. 8. All long flights of stairs to have smoke-stops in each flight, properly constructed. 9. No pipes for conveying hot air or steam can under the law be placed nearer than one inch to any wood-work unless protected to the satisfaction of the inspector by suitable guards or casings of incombustible material. 10. No wooden flue or air-duct of any description can be used for heating or ventilating purposes. 11. A space of at least one inch to be left between all wood-work and the chimneys, also around all hot-air, steam and hot-water pipes ; these spaces around chimneys and pipes, where they pass through floors, to be stopped with metal or other fire-proof material, smoke-tight. Steam and hot-water pipes to have metal sleeves and collars. All channels and pockets for gas, water and soil-pipes to be made smoke- tight at each floor. 12. The space around all metal or brick ventilating ducts must be fire- stopped at each floor with metal or other fire-proof material, as approved by the inspector. 13. All chimneys to be plastered with one good coat of brown mortar, on the outside .of brick-work, from cellars to roof. 14. The ceiling of furnace or boiler and indirect radiator rooms must be plastered on metal lathing. There should be not less than one foot in height of open air space between the tops of furnace or boiler casing or any smoke- pipe and the ceiling. 15. The entire cellar ceilings of schoolhouses and other buildings used for public purposes mu'st be plastered on metallic lathing. So much of these specifications as applies to any building should be incor- porated by the architect in his specifications for said building, and the clauses therein incorporated should be indicated by their numbers in the specification filed with the inspector. These specifications are to be followed in every building subject to the provisions of section 22 of chapter 104 of the Revised Laws, unless omitted or changed in some part by special consent of the inspector. Other provisions than those herein specified, to prevent spread of fire, may be required by the inspector if deemed by him to be necessary. Means to Extinguish Fire. Chapter 104 of the Revised Laws of Massachusetts requires that means to extinguish fire be provided in certain buildings, as fol- lows : Section 25. A building which is used, in whole or in part, as a public building, public or private institution, school house, church, theatre, public hall, place of assemblage or place of public resort, THE SCHOOL HOUSE. 11 Section 26. Each story above the second story of a building which is subject to the provisions of the preceding section shall be supplied with means of extinguishing fire, consisting of pails of water or other portable apparatus or of a hose attached to a suitable water supply and capable of reaching any part of such story ; and such appliances shall be kept at all times read}' for use and in good condition. Although not required by the Massachusetts laws, it is advisable that each story, including the basement, should be provided with a chemical fire-extinguisher, or a stand-pipe and hose not less than two inches in diameter. Suitable and neat hose racks should also be provided in the corridors. In order that the stand-pipe may be tested to see if it is full of water, and to do this without wetting the hose, it is advisable to place in the stand-pipe, just below the valve in each story, a small try-cock. Care should be taken that the connection with the street water main is not less in diameter than that of the stand- pipe in the building. Basement. The basement should not be less than ten feet high and twelve feet is preferable. It should be well lighted, and when practicable, at least five feet should be above ground. The basement floor should be of concrete, not less than four inches thick, with a well-smoothed covering of three-quarters of an inch thick of rock asphalt or Portland cement. Rosendale or similar cement is unsuitable for the top covering of a schoolhouse basement on account of being easily worn and broken by the pupils. When so used there is complaint of the dust arising from the fine detached particles of cement. On wet, filled or clayey ground it is advisable to cover the outside of the foundation and bottom of the basement concrete floor with boiled asphalt to prevent moisture or earth exhalations from entering the building. The floor of the boiler, furnace and coal rooms should be paved with brick, preferably set on edge in cement mortar. The floor of the sanitary and playrooms should be graded to some convenient point, at which a drain with a perforated cover is placed, in order that the floor may be thoroughly washed by water from a hose. The drain for this purpose should be well trapped and not connected with the drain from the sanitary fixtures. The heating apparatus, cold-air rooms, sanitary, play and lunch- 12 THE SCHOOL HOUSE. rooms should be in the basement, and when a manual training room or gymnasium is there, the wood floor should be laid on screeds embedded in concrete, and the space between the screeds filled with cement or cinder concrete. A chemical laboratory should never be placed in the basement. The flooring of the rooms over the cold-air room should be well protected by some non-conducting material to prevent the cold from striking up through the floor of the first story. This is sometimes done at a moderate expense by fastening two or more thicknesses of building or thick asbestos paper between the floor timbers, about half-way between the metallic lathing and the floor boarding, holding it in place by strips of furring nailed to the sides of the floor-beams. A bicycle run and stalls or racks should also be provided. Galvanized iron ash-holders should be provided for removing the ashes from the boiler or furnace room, also a convenient ash- lift or door. Suitable soapstone or iron sinks, drinking-cups and wash-basins should be provided in the play-rooms ; also in the boiler or furnace- room for the use of the janitor or engineer. Where practicable, a janitor's room and work -bench should be provided. Hose and pipe should also be provided for washing. Danger from fire is greater in the basement than in other parts of the building, and as little wood finish should be used there as possible. It is advisable that the boiler or furnace rooms should be fire- proof ; or, at least, of slow burning construction, and that metal- covered doors be used for these rooms. The basement stairways should be shut off from the corridors by doors to prevent smoke from rapidly filling the corridors and upper stairways. Closets should not be allowed under stairways, as they frequently become receptacles for inflammable material, such as waste paper, oil-cans, etc. Corridors. Corridors should be wide and well lighted. Twelve feet is not too wide, and when the outer garments of the pupils are hung there fifteen feet is to be preferred. In small schoolhouses the outer garments can be hung there, either on wall supports, or in stalls preferably made of wire grill work of about one-eighth inch diameter wire, and about two inches THE SCHOOL HOUSE. 13 diamond mesh. This gives a much better chance for the air to circulate than when wood partitions are used, and the pupils, when the wire grill work is used, can be kept in view of the teachers. The top of the grill work is usually from five to six feet, and the bottom about one foot above the floor. A shelf of wire grill, on which to place overshoes, is often put at the bottom of the upright grill. In some cases another shelf is placed near the top. Hat and coat hooks in primary schools are placed four feet above the floor, and in other schools five feet. Thirty running feet for a fifty seat room is usually the minimum hanging space. It is advisable to run two lines of one and one-quarter inch steampipe a short distance above the floor and under the clothing, for the purpose of drying in stormy weather. Where practicable, umbrella racks are advisable. All corridors and clothing rooms should be well ventilated ; but it is not requisite that a separate air supply should be provided, as the leakage of outside air and the frequent opening of outside doors will generally furnish the required amount of fresh air. A good exhaust duct is, however, necessary. " Foot- warmers " should be in all cases provided in the lower corridor, in order that in cold or stormy weather the pupils may be provided with means for drying and warming their clothing and feet. The air supply for the foot warmers may be taken in through the risers in the vestibule stairs, or it may be rotated from the corridor. In large buildings, or where the cost does not prevent, separate coat rooms may be provided. E. M. Wheelwright, in his excellent work on schoolhouse archi- tecture, says, " specially designed separate clothing rooms add about from four to four and one-half per cent to the cost of the building." A hand bowl and faucet or drinking fountain should be provided in each corridor, and in some cases a mirror, soap and towels are added. Glass panels in the class-room doors assist materially in lighting the corridors and enable the teachers to observe what is passing there. Transoms over the doors are also desirable. In some buildings, where long and difficultly lighted corridors are designed, small windows near the ceiling of the class-rooms have been used to good advantage to assist in lighting the corridors. 14 THE SCHOOL HOUSE. Vestibules. Vestibules are desirable for all schoolhouses. They should be well lighted and have self-closing doors. In cold and stormy weather, where no vestibules are provided the corridors and other parts of the building are often very rapidly cooled, especially before the session or during recess, by opening outside doors directly into the corridor. In the matter of economy of fuel, if for no other reason, vesti- bules should always be provided in schoolhouses. If it is not practicable to construct a vestibule, a temporary out- side storm porch should be constructed of matched boards for use in winter, and capable of being removed for warm weather. Exits. There should be at least two ways of exit from every schoolhouse. The stairways and outside doors' should be placed as far apart as practicable and should be not less than four feet wide. Five feet is better. The Massachusetts inspectors require means of exit equal to twenty inches for each one hundred persons accommodated in a public building ; but no stairway to be less than four feet wide in the clear. (For theaters the law requires forty inches for each ipo persons, and no exit to be less than five feet wide.) When the expense can be incurred it is desirable that stairways in brick school-buildings be made fire-proof and enclosed in brick walls. The stairs should be of iron, and in the treads should be embedded safety treads, not less than five and one-malf inches wide, and made of a combination of steel and soft metal, or rubber covering can be advantageously used. In wooden buildings the sides of the stair-stringers should have the spaces between the studs or wall-furrings so stopped with brick or mortar as to effectually prevent fire from passing up between the studs or furrings back of the stair-stringers, and the soffits of enclosed stairs, and the partitions on the stairway-side should be plastered on expanded metal lathing. At least two cut-offs or fire stops should be put in each stairway. Enclosed stairways should have a substantial hand-rail on each side. Open stairways should have a hand-rail on the wall side, and especial care should be taken that the outer posts and balusters are strong enough to prevent being broken or pushed out of place should the stairway become overcrowded in case of panic. THE SCHOOL HOUSE. 15 Circular stairways or winders should never be placed in school- houses or places of assemblage. In the lower grade schools, risers should preferably be six inches with twelve-inch tread ; in other grades, risers not more than seven inches, with ten and one-half inches tread. The product of the rise and run should not be less than seventy or more than seventy-five. There should not be less than two, nor more than fifteen steps between landings, and landings not less than four feet long. The ordinary fire-escape, such as is used on factories, hotels, tenement-houses, etc., should never be placed on a school-buildi?ig unless it is impossible to provide other -ways of exit. The danger would be very great if in case of fire an attempt should be made to have a large number of children go down the narrow fire-escapes of the ordinary design. The pupils would be very likely to become frightened when they looked down from the open fire-escape, would hesitate, stop, and be pushed by those in the rear, and a panic would ensue. The writer has not for many years required the ordinary fire- escape to be placed on any schoolhouse. When additional means of exit from a schoolhouse must be provided, it should be by enclosed stairways with hand-rails on each side. Outside main entrance and vestibule doors should open out or both ways. The standing leaf of all pairs of doors leading to ways of egress should be fastened by face T-bolts, operated at top and bottom by one handle placed at a convenient height from the floor. Edge bolts should not be used, on account of the difficulty of opening quickly. Schoolhouse doors should never be fastened during school hours in a manner that will prevent them being quickly opened from the inside. If desirable to prevent persons from entering the building, the door-knobs may be arranged to open the door from the inside, but not from the outside. An electric bell should be provided for the use of persons desiring to enter. Doors used as exits from the building should be at least equal in width to the stairways. No door opening inward at the bottom of any stairway should be allowed in any public building. Door-checks for outside doors will soon save the additional cost in the amount of fuel burned in cold weather. 16 THE SCHOOL HOUSE. From each class-room at least one door should open out, and class-rooms on the same story or side of the corridor should have connecting doors. Windows. Windows in class-rooms should preferably be four feet between jambs, three feet above the floor, and about six inches, or only enough for the finish, from the top to the ceiling. Four lights of glass in each window is a desirable number. Three windows at the rear and four at the left of the pupils give a very good light for the ordinary sized school-room, lighted from two sides. When only lighted from the left of the pupils' desks, five windows are preferable if the construction of the building will allow it. Arched windows are objectionable in a class-room. Transoms may be allowed for summer ventilation where a gravity system is used ; but double windows are more desirable, especially on the sides most exposed to the prevailing winter winds. A very considerable saving of fuel is made by their use, and they also to a large extent prevent the cold drafts caused by the rapid cooling of the air on the glass surface. Double-glazed sash, that is, two lights of glass set with about one-half-inch air space between them, is sometimes used to good advantage, but is not as desirable as double run of sash. When double glazing is used care should be taken that the glass is thoroughly cleaned and dried before setting. When either the gravity or mechanical system of ventilation is in use all windows, transoms and doors in class-rooms should be closed in order to obtain the best results. Windows should have an eye or a depressed piece of metal set into the upper part of the sash, by means of which they can be easily lowered or raised with a window pole or rod. Transoms should be hung at the bottom and opened or closed by adjusting rods. Class-room doors opening into a corridor should have a large light of heavy glass set in the center and about four feet above the floor. Windows grouped as mullions do not give as satisfactory light as when equally spaced in the outer wall. Basement windows should when practicable be about four feet high and correspond in width to those in the stories above. THE SCHOOL HOUSE. 17 Care should be exercised that all spaces about the window frames are caulked or made as tight as possible. Neglect of this precau- tion is often a cause of complaint of uncomfortable drafts. Venetian or other blinds are very objectionable in school rooms. Roller shade curtains, which can be adjusted to raise or lower from either the top or bottom, by means of a slide or a rod at each side of the window, and operated by a cord to hold the curtain in any position, are very desirable, and enable the teacher to regulate the light in a satisfactory manner. Many of the modern school buildings are now provided with these adjustable curtains. They assist in partly solving the much-discussed problem of using light from the north or other points of the compass. Much has been written regarding the amount of light admitted to a schoolroom, and from which point of the compass it should come. To carry out the theories of some writers would require the class- rooms to be of a height that would very materially increase the cost of the building. By having a sufficient number of wide windows which extend nearly to the ceiling, and by the judicious use of properly colored adjustable curtains, many of the objections can be in a great measure overcome. The theory that only a north light should be used in a school- room will often lead to objectionable conditions in the heating and ventilation. Where a corridor is located north or northwest from class-rooms a more even temperature and better circulation of air is obtained than where the class-rooms are exposed to the prevailing winds, which in Massachusetts are from the northwest and north in the winter. Class-Rooms. The standard generally adopted for a class-room in Massachu- setts, for what is usually called a fifty seat room, is 32 feet long, 28 feet wide and 12 feet high. In the lower grades sometimes 56 seats are provided, but this large number is not recommended. Grammar and the high grade rooms are commonly seated for 42, 47, 48 or 49 pupils. Twenty-eight by thirty-two feet gives a floor space of 896 square feet, and allows 21.33 square feet of floor space for 42, 19.06 for 47, 18.66 for 48, and 18.28 for 49 pupils. Allowing one teacher 18 THE SCHOOL HOUSE. per room gives respectively 20.83, 18.16, 18.28 and 17.92 square feet of floor space for each occupant. The rooms being 12 feet high gives 10,752 cubic feet of air space. This space includes that occupied by the furniture and persons in the room. Usually this is not taken into consideration, but for accurate calculation it should be. Allowing 42, 47, 48 and 49 pupils, this 10,752 cubic feet of air space gives respectively 256, 228.7, 224 and 219.42 per pupil, or, allowing for one teacher, we have 250.04, 224, 219.42 and 215.44 cubic feet of air space per person. For approximate calculation we may estimate an ordinary school- room in Massachusetts as containing 10,000 cubic feet of air space. While these amounts of floor and air space do not quite agree with the recommendations of a number of writers, yet with a • properly designed system of heating and ventilation 30, 40 or 50 cubic feet of air per minute may be supplied to each occupant with- out uncomfortable drafts being perceived. With wide and high windows, properly located, very little com- plaint can reasonably be made as to satisfactory lighting. At least this has been the experience of the writer while making many tests of heating and ventilation, and in many conversations with teachers and pupils. Twelve feet appears to be a desirable height for ordinary class- rooms where the inlets and outlets for ventilation are of ample size and properly located. This height will allow a good circulation of air, while a lower stud may sometimes cause uncomfortable drafts. A higher stud than 12 feet increases the cost of the building without giving an adequate return. In rooms 14 feet high the circulation of air is no better than in those 12 feet high. Skating. The convenient arrangement of seats in a class-room will depend upon the number of pupils to be accommodated. In assembly and public halls (except theaters) the Massachusetts inspectors allow six square feet of floor space for each person. This includes aisles, and the open spaces hi front of the stage or platform and at the rear of the seats. In determining the width of exits from halls or places of assem- blage, divide the number of square feet of floor space in front of the stage or platform by six for the seating capacity. The width of the THE SCHOOL HOUSE. 19 exits is determined by the seating capacity ; allowing 20 inches for each 100 persons; but no exit to be less than four feet wide. It is intended that the audience shall pass out in lines 20 inches wide ; that is, 200 persons should have at least forty-eight inches in width of exit; 300, sixty inches ; 400, eighty inches, etc. Lecture-rooms in the larger schoolhouses are generally seated in amphitheatre form, and seats with a broad arm or small table- attachment are desirable to enable the pupils to conveniently make notes of the lecture. In class-rooms the seats should be arranged in a manner that will allow the light to reach the pupils from the left and rear when the room is lighted on two sides, and from the left when the light is from one side only. When the light comes from the right the effect is bad, especially when the pupils are writing, the shadow of the hand being very trying to the eyes. Class-room seats should never be placed in a position which requires the pupils to face the windows. The teacher, not being obliged to remain in one position, can better face the light occa- sionally than to require all the pupils to do so constantly. In most modern schoolhouses the teacher's platform is omitted, and a movable desk which can be placed in any desirable position is provided. The ordinary size for a teacher's desk is about 50 inches long, 30 inches wide, and 31 inches high. Seats and desks, the height of which can be adjusted to the size of the pupils, are much better than those which require pupils of different ages and height to have the same size desk and seat. There are several styles of adjustable seats and desks in the market, and money expended in this manner is well invested for the health and comfort of the pupils. The seats and desks should be adjusted to the size of the pupils at least as often as the beginning of each school term. The old-fashioned double seats and desks occupied by two pupils should not be tolerated in any modern class-room. Seats and desks in class-rooms should be adjustable in order that they may be fitted to the needs of each individual pupil. Ill-fitting seats and desks are often responsible for round shoulders, spinal curvature, and impaired eyesight. There are measuring gauges by means of which the height of seats and desks may be readily adjusted. 20 THE SCHOOL HOUSE. The following show samples of adjustable and other kinds of furniture used in Massachusetts schoolhouses. Fig 1. Fig. 2. Fig. 3. Fig. 4. Tablet Arm Fig. 5. Figs. 6 and 7. Fig. 8. THE SCHOOL HOUSE. 21 Side aisles are usually from three to four feet wide. Aisles between desks are usually 18 inches, but vary from 16 to 24 inches, according to size of the room and the number and size of desks. In high schools the distance between rows of desks is often 30 inches, and the desk tops are 20 by 26 inches. In schoolhouses having a room for the principal or head master there will generally be found a roller-top desk for his use, and frequently a lounge and extra chairs are provided. A carpet and some appropriate pictures add to the general appearance of the room. The following sizes may be considered as desirable for pupils of different ages and grades. Fig. 9. Ages. 5 or 6 years 6 or 7 years 7 or 8 years 8 or 9 years 9 or 10 years 10 or 11 years 11 or 12 years 12 or 13 years 13 or 14 years Grades. Dimensions of Desk Top in Inches 12 x 18 13 x21 16 x24 18 x24 20 x 26 Range of Height of Adjustment in Inches. Chair. 91 to 13* 10| to 15 12$ to 17 131 to 181 Desk. 17J to 224 18 to 25 204 to 29 23 to 31 Age of Pupil. 4 to 8 years 5 to 12^ears 7 and upwards 11 and upwards High-school desks are usually made with tops either 18 x 24 inches or 20 x 26 inches. Dimensions of Desk Top. Space Occupied. 12 x 18 inches 1 From side to side, 18 inches From front of desk to rear of chair, 25 inches 13 x 21 inches { From side to side, 21 inches From front of desk to rear of chair, 27 inches 16 x 24 inches { From side to side, 24 inches Front front of desk to rear of chair, 30 inches 18 x 24 inches 1 From side to side, 24 inches ) From front of desk to rear of chair, 34 inches 20 x 26 inches { From side to side. 26 inches From front of desk to rear of chair, 36 inches Allow one inch between back of desk and back of chair. 22 THE SCHOOL HOUSE. Blackboards. Class-room blackboards should be of slate and set on the two inner walls. Where an appropriation will allow, all available space should be so occupied. Not that the space between the windows should be used for daily exercises ; but exhibition draw- ings or artistic designs drawn there add much to the general appearance of the room. Blackboards should be at least 3 feet high ; 3 feet 6 inches or even 4 feet is not excessive in the higher grade rooms. In primary schools they are set 2 feet 4 inches, and the other grades 3 feet above the floor. A chalk and eraser receiver 2^ inches wide should be set below the blackboard. In lecture-rooms sliding blackboards set in frames that will allow two or more boards to be used in succession are advisable. Clocks, Thermometers and Pictures. A clock should be provided in each class-room. In many of the larger buildings electric clocks connected with a regulating one in the head master's room are provided in the several class-rooms, and indicate the time for various recitations or change of classes. A thermometer should also be placed in each class or recitation room, and if proper attention is given to the indicated temperature more satisfactory results will be obtained, not only as to the com- fort of the teacher and pupils, but a considerable saving can be made in fuel. It is advisable to place the thermometer about on the breathing line of the pupils when in their seats, and to hang it in a location where it will be but little acted on by the rays of the sun, or by cold outside walls or drafts from windows or doors, or opposite a warm-air inlet. On the teacher's desk or on an inside wall is generally the best location. At least one thermometer should be placed on the outside of the building in such a position as will screen it as much as possible from the direct rays of the sun. This will be of service to the janitor in regulating his fires, and thereby controlling to a consid- erable extent the amount of fuel used. Moulding for hanging pictures is often provided in schoolrooms and a few appropriate pictures add much to the general appearance of the room. THE SCHOOL HOUSE. 23 In many of the large school buildings appropriate plaster casts are provided, which with artistic pictures in various parts of the building present a fine appearance and are appreciated by teachers, pupils and visitors. In many of the large school buildings provision is often made for additional rooms : for an assembly hall, manual training, gymnasium, chemical, physical and biological laboratories, type- writing and stenography, business course, cooking, lunch, teachers, clothing, sanitary, emergency, library, and a janitor's workroom ; also book cases and storage closets. In many schoolhouses, telephone connection is provided between the class-rooms and for the janitor and the principal's room. This is more desirable than speaking tubes, which are, however, used to a considerable extent. In many buildings telephone connection is provided through the '* central " telephone office with other buildings and with the superintendent of schools. Fire-alarm boxes are often placed in or near schoolhouses for use in case of emergency. ' CHAPTER II. AIR. THE atmospheric air we breathe consists of a mechanical mixture of approximately 21 parts of oxygen and 79 parts of nitrogen, and usually about four parts of carbonic acid in 10,000 parts of air. A large number of analyses taken in different places by different persons show that when the air is not particularly contaminated by local conditions four parts of carbonic acid gas in 10,000 parts of air may be considered a fair standard. A number of other substances are also found in air, such as ozone, watery vapor and organic matter given off by living animals, dust particles, microbes, ammonia compounds, sulphuretted hydrogen, sulphurous and sulphuric acid, nitrous and nitric acid, carbonic oxide, sewer gas and many substances produced by various sources of contamination ; also some 30 species of moulds and yeasts, together with the recently discovered argon and other substances. In breathing, the movements of respiration follow each other at the rate of 18 or 20 a minute. Quetelet gives the respirations per minute at : Birth, 44 ; five years, 26 ; from 15 to 20 years, 20 ; from 20 to 25 years, ,18. 7 ; from 25 to 30 years, 16 ; from 30 to 50 years, 18.1. Dr. Edward Smith found from numerous experiments that the average depth of respiration was 33.6 cubic inches' when at rest. Different authorities give the amount of air inspired and expired as from 26 to 40 cubic inches. The movements of respiration are accelerated by muscular action. When the lungs have been emptied by expiratory effort they still contain in the smaller bronchi and air sacs a quantity termed residual air, which cannot be expelled, and which is estimated by different authorities as from 40 to 100 cubic inches. A fair average may be taken as 75 cubic inches. Allowing the amount of air inspired and expired to be 30 cubic inches at each respiration, and 20 respirations per minute, makes 600 cubic inches of air, or .34 cubic feet of air actually used per minute. The air inhaled passes through the lungs and is deprived of a percentage of its oxygen, which passes into the blood, where it is THE SCHOOL HOUSE. 25 taken up by the tissues, which are oxidized and carbonic acid gas and other impurities are taken away by the expired air, which, on leaving the lungs, contains about 400 parts of carbonic acid instead of the four parts in 10,000 parts of air when inhaled. Oxygen is the life-giving element of the atmosphere and is essential for the support of life and also combustion. In the human body there are constantly going on chemical changes which may be compared to the action of a fire, Acting upon the excess of carbon and other ingredients in the blood, chemical compounds are formed and thrown off by the breath of the individual. Thus the life-giving element of the air is reduced, and poisonous and harmful substances arc introduced in its place. The nitrogen is practically inert in the process of respiration and combustion, and is not affected by passing through the lungs or a fire. It renders the oxygen less active and absorbs some of the heat produced. Carbonic dioxide (C0 2 ), or carbonic acid, is the result of combustion of carbon, and although not in itself considered a poisonous gas, yet it may cause the death of a person by suffocation for want of the life-giving oxygen. As a product of respiration and combustion, carbonic acid is taken as an indication of the amount of other impurities present, and should not exceed eight parts in 10,000 in air intended for breathing, and in many well-ventilated buildings it is often found less than six parts. Carbonic oxide (CO) is distinctly a poison, and has a character- istic reaction on the blood. Carbonic oxide is doubly dangerous, for, like carbonic acid it is devoid of smell. Persons narcotized with carbonic acid may be restored to life and health by prompt removal to the fresh air, or by artificial respiration. Poisoning with carbonic oxide is a much more serious matter, and admitting fresh air, or even pure oxygen gas, is often power- less to overcome the poison of carbonic oxide. When the draft in a furnace or heater is insufficient the combus- tion is only partly complete, full oxidation of the carbon of the fuel does not take place, and carbonic oxide is formed. The escape of this gas into a room should be carefully guarded against. Especial care should be taken that there are no open joints or cracks in the furnace or heater. Organic nitrogenous substances exhaled with air from the lungs are poisonous, and their presence may be noted in the stagnant, vitiated air of a crowded and unventilated room. 26 THE SCHOOL HOUSE. The disagreeable odor known as the " schoolhouse smell" is occasioned by these substances and the odors given off by the skin, stomach, decayed teeth, and unclean persons and clothing. Brown Sequard and Arsonval made extended researches into the nature of these nitrogenous poisons. They condensed the exhala- tions from the lungs of men and dogs and obtained a liquid with an alkaline reaction. From two to four cubic centimeters of this liquid, injected into the veins of animals, caused a slowing of the respiration, dilation of the pupils of the eyes, great muscular weakness and a very rapid pulse. When from 10 to 12 cubic centimeters were used death speedily followed, even when the fluid had been boiled. Brown Sequard arranged eight air-tight cages, connected with glass tubes from one to the other, and by means of an aspirator air was made to pass from cage to cage successively. A rabbit was placed in each cage. The one in the first cage received pure air; the second, air vitiated by the first animal ; the third, air polluted successively by two rabbits, etc. Special provisions were made for the removal of excrement. The eighth rabbit died in two days, the seventh in three days, and so on till the death of the third one, in eight days. The first and second animals remained alive. Quantitative analysis of the air in the several cages showed the carbonic acid could not have caused the death of the rabbits. With bits of pumice stone impregnated with sulphuric acid placed in the glass tube between the sixth and seventh cages, the rabbits in the seventh and eighth cages remained well. The sulphuric acid neutralized the particular poison. Claude Bernard made a series of experiments which tend to show that the system may gradually, in some degree, acquire a toleration of the poisonous principles in rebreathed air. A sparrow was inclosed in a glass globe. It hopped about for an hour as actively as usual, and then gradually showed signs of suffering from rebreathing the air poisoned by its own breath. At the end of the second hour another sparrow was placed in the glass globe. It was asphyxiated by the foul air" and soon died. At the end of the third hour the first sparrow became unconscious. Taken out into the open air it soon recovered ; when replaced in the glass globe it died at once. When expired, air leaving the lungs contains about 400 parts of carbonic acid in 10,000 of air, together with other impurities. To dilute and remove these products of respiration a large quantity of pure air must be supplied. THE SCHOOL HOUSE. 27 Different writers vary as to the amount of air required for the good ventilation of occupied rooms. Parkes fixes the amount of fresh air per person per hour For adult males, 3,500 cubic feet. For adult females, 3,000 cubic feet. For children, 2,000 cubic feet. For a mixed community, 3,000 cubic feet. Pettinkoffer recommends 2,100. Dr. Billings, from 850 for children 6.25 years old to 2,000 for those of i4.88. It may be fairly considered that an ordinary adult man expires .7 of a cubic foot of carbonic acid per hour, and a person about twelve years old averages .6 of a cubic foot, and that 3,000 cubic feet of air per hour per person is required for good ventilation. Prof. Carpenter, in his excellent work on ventilation, says, " If we take the CO., as an index of the character of ventilation, and consider that each person uses one-third of a cubic foot of air per minute, and that the respired air contains 400 parts in 10,000 of CO.,, while the entering air contains but 4, we can calculate the amount of air which must be provided to maintain any standard of purity desired. The formula for this operation would be as follows : '* If a = the parts of C0 2 in 10,000 thrown out in respiration, or other impurities ; if b = the cubic feet of air used per minute ; if n = the standard of purity to be preserved, expressed as the num- ber of units of CO._, permissible in 10,000, and C = the number of cubic feet of air required, we shall have C — a ^ ~ («— 4) " For conditions considered for each adult person, a =400, b = £, so the formula becomes 133 C = (n — 4) By taking n as 8, C = 33, and n as 10, C = 22." This very nearly agrees with several hundred tests made by the writer. An approximate rule for calculating the amount of air required per capita per hour to keep the CO., down to six parts in 10,000 of air in schoolrooms and halls, is by allowing 3,000 cubic feet for this purpose. 28 THE SCHOOL HOUSE. For other ratios, divide 6,000 by the difference between normal, or four parts in 10,000, and the ratio of purity required. Example : 6 — 4=2, 6,000 -f- 2 =3,000 for 6 parts. 7—4=3, 6,000-7-3 =2,000 for 7 parts. 8—4 = 4, 6,000 -r- 4= 1,500 for 8 parts. 9—4=5, 6,000-7-5 = 1,200 for 9 parts. 3,000 -7- 60 = 50 per minute for 6 parts. 2,000 -7- 60 = 33.33 per minute for 7 parts. 1,500 -7- 60 = 25 per minute for 8 parts. 1,200 -7- 60 = 20 per minute for 9 parts. The standard for schoolrooms adopted by the Massachusetts Inspectors of Public Buildings is a minimum of thirty cubic feet of fresh air per pupil per minute. In many of the well-ventilated school buildings in Massachusetts from 40 to 50 cubic feet of fresh air per minute is furnished for each pupil. Fifty cubic feet of fresh and properly warmed air per minute per person is an ample but not excessive amount for good ventila- tion in a schoolroom. Humidity. The amount of C0 2 expelled in respiration is increased greatly by external cold and diminished by heat ; increased by moist and decreased by dry atmosphere. Humidity or moisture in air has much to do with comfort and the sensation of heat or cold. When the air is saturated with moisture water is deposited on bodies which readily conduct heat and are of a lower temperature than the surrounding atmosphere. No evaporation from the body will take place when the air is saturated with moisture. When the air is deprived of moisture it evaporates water from the body, causing an unpleasant sensation. Heat increases the power of air to contain moisture, but to remove moisture from the air it must be cooled. In schoolhouses where an ample quantity of moderately warmed air is supplied there is seldom complaint of dryness of the air. It has been found that much better results have been obtained when the extra amount of fuel used to evaporate a considerable quantity of water has been expended in warming a larger quantity of air. THE SCHOOL HOUSE. 29 It is seldom that any special provision is made to moisten the atmosphere of schoolrooms- Should a little moisture he desired in schoolhouses heated by steam, it can be supplied by opening an air-valve in a radiator and allowing steam to escape into the air passing over the radiator. To feel comfortable and produce the best results in ventilation, air should be from 50 to 60 per cent saturated with moisture. Lights. The lights used in a room are one source of vitiation of air. An ordinary gas burner contaminates a quantity of air equivalent to that vitiated by from four to five persons, and allowance should be made for this quantity in calculating the amount of fresh air required. In large assembly halls lighted by gas special ventilation should be provided above the clusters of gas lights to quickly remove the vitiated air and prevent it from mingling with the air of the room. Where electric lights are used it is only required to allow for their heating effect in large or crowded places of assemblage. The size of ordinary schoolrooms should be such that a sufficient quantity of fresh air can be introduced and foul air removed without causing uncomfortable drafts. It is the number of occupants and not the size of the room that determines the amount of air that should be supplied. Rules calling for the change of air in a room a given number of times per hour, without regard to the number of occupants, are erroneous, and should not be adopted in designing a system of ventilation. Testing the Purity of Air. It is not always convenient to have a chemical test made in a laboratory of the purity of air from a schoolroom or assembly hall ; but an approximate test can be made in the schoolroom by the use of a simple apparatus known as " Professor Wolpert's Air Tester," and, if carefully made, will indicate near enough for all practical purposes whether the air is contaminated to such an extent as to render it unfit for respiration. A comparison of thirteen tests of air for carbonic acid (CO Q ) made with a Wolpert air tester and of air taken at the same time and placed in glass flasks for laboratory analysis, showed an average difference of only sixty-seven one hundredths of one part in ten thousand parts of air — the laboratory analyses showing only 30 THE SCHOOL HOUSE. this quantity of carbonic acid (C0 2 ) in excess of the amount shown by the Wolpert tester. Care must be taken to have a saturated solution of clear lime- water and also in using the apparatus. The apparatus consists of a simple rubber bulb (A) of a capacity of fifty-two cubic centimeters, a glass outlet tube (B) with a constriction near its extremity (E). The glass test-tube (C), which is twelve centimeters in length and twelve millimeters in diameter, has a horizontal mark (F) near the bottom, indicating the point to which it must be filled with perfectly clear lime-water to contain three cubic centimeters. The bottom of the tube has a black mark (D) made by attaching a piece of black glass. A small wooden stand, a brush or swab, a vial of vinegar for cleaning the tube, and a bottle of perfectly clear and saturated lime-water, complete the outfit, and for convenience in carrying may all be inclosed in a neat case. Where a number of tests are to' be made time may be saved by having several test-tubes and bulb outlet tubes in the case, as a clean tube should be used for each test. DIRECTIONS FOR USING PROFESSOR WOLPERT'S AIR TESTER. By S. W. Abbott, M.D., Secretary Massachusetts State Board of Health. In order to use the instrument, the lime-water (saturated solution) should be poured into the test-tube till it reaches the horizontal mark. Press down the bulb with the thumb, so as to expel the air within it as completely as possible, and allow it to fill Prof. WOLPERT'S AlR TESTER f***S^ with the air oi the apart- E; _^ m ^ ■ i .. \ ment, insert the small tube into the lime-water nearly to the bottom, and again expel the air with moderate rap- F IG - 10- idity, so that the bubbles may rise nearly to the top of the tube, but do not overflow, taking care to continue the pressure of the thumb till the small tube is removed from the lime-water. Repeat this process until the mark upon the bottom of the test-tube is ob- scured by the opacity produced by the reaction of the carbonic acid upon the lime-water, the observer looking downwards through the lime-water, from the top of the test-tube. With very foul air it is necessary to examine the mark after filling and discharging the bulb a few times only; with good air it must be filled twenty-five times and upwards. After each observation the test-tube must be washed out and wiped dry. If a white incrustation forms upon the tube, it may be easily removed with a little vinegar, after which the tube should be thoroughly washed with pure water and dried. > 41 34 15 2.36 I 6 3 8 633 42 7.150 3,900 11.1150 48 re 3 30 4 15 2.3 1 a 8 552 37 7,000 3,900 10.900 48 17 3 49 3 16 2.02 1 6 3 8 682 45 7.400 3.900 11,300 48 17 3 41 34 16 2.36 1 il a 8 c.Cs 45 7,500 3,900 11.400 48 17 3 30 4 16 2.3 :; s 590 39 7,400 3,900 11,300 54 15 3 60 3 14 2 47 XJL 3 2 3 s 725 48 7800 4.200 12,000 54 15 3 49 34 14 2.82 XX 3 2 a 8 703 47 7,900 4,200 12.100 54 15 3 42 4 14 3.22 1 L 3 2 a s 696 46 8.250 4,V00 12,450 54 16 3 60 3 15 2.47 XL 3 2 3 8 116 52 8,200 4,400 12.600 54 16 3 49 34 15 2.82 XX 3 2 s 8 752 50 8,300 4,400 12,700 54 16 3 42 4 15 3 22 XL 3 2 -3 8 745 50 8,700 4,400 13,100 54 17 3 60 3 16 2.47 11 32 i 8 826 55 8,650 4,400 13,050 82 THE SCHOOL HOUSE. TABLE 11 . — Continued Diam. Length Number Outside Length Area Thick- Thick- Rated Approxi- Approxi- mate Weight of of of Diam- of through ness of ness of Heating Horse- mate of Castings Total Shell. Shell. Tubes. eter of Tubes. Tubes. Shell. Heads. Surface. Power. Weight of and Weight Tubes. Boilers. Fixtures. In. Ft. In. In. Ft. Sq. Ft. In. In. Sq. Ft. H.P. Lbs. Lbs. Lbs. 54 17 3 49 34 16 2.82 11 32 2. 8 801 53 8,900 4,400 13,200 54 17 3 42 4 16 3.22 11 32 .3 8 793 53 9,150 4,400 13,550 54 18 3' 60 3 17 2.47 22 8 876 58 9,100 4,400 13,500 54 18 3 49 H 17 2.82 11 32 2 8 850 57 9,200 4,400 13,600 54 18 3 42 4 17 3.22 11 32 2 a 841 56 9,600 4,400 14,000 60 15 3 80 3 14 3.3 8 1 2 942 63 10,450 5,150 15,500 60 15 3 64 U 14 3 69 3 8 1 2 898 60 10,650 5,150 15,800 60 15 3 58 4 14 4.45 3 8 1 2 931 62 11,350 5,150 16,500 60 16 3 80 3 15 3.3 3. 8 1 2 1,008 67 11.050 5,150 16,200 60 16 3 64 34 15 3.69 2 8 1 2 960 64 11,250 5,150 16,400 60 16 3 58 4 15 4.45 3. 8 1 2 996 66 11,950 5,150 17,100 60 17 3 80 3 16 3 3 2 8 1 2 1,073 72 11,800 5,150 16,950 60 17 3 64 34 16 3.69 2 8 - 1 2 1,022 68 12,000 5,150 17,150 60 17 3 58 4 16 4.45 2 8 JL 2 1,061 71 12,700 5,150 17,850 60 18 3 80 3 17 3.3 2 8 1 2 1,139 76 12,560 5,150 17,710 60 18 3 64 u 17 3 69 2. 8 1 2 1,085 72 12,780 5,150 17,930 60 18 3 58 4 17 4.45 2. 8 1 2 1,125 75 13,450 5,150 18,600 66 16 4 110 3 15 4 54 16 1 2 1,348 90 14,600 5,400 20,000 66 16 4 79 34 15 4.55 -Z- 1 6 1 2 1,168 78 14,600 5,400 20,000 66 16 4 62 4 15 4.76 _3_ 16 1 2 1,073 72 14,600 5,400 20,000 66 17 4 110 3 16 4 54 -T- 16 1 2 1,436 96 15.500 5,400 20,900 66 17 4 79 H 16 4.55 .1. 16 1 2 1,244 83 ' 15,400 5,400 20,800 66 17 4 62 4 16 4.76 .1. ] 6 1 2 1,142 76 15 500 5,400 20.900 66 18 4 110 3 17 4.54 .1. 1 6 1 2 1,524 102 16,300 5,400 21,700 66 18 4 79 34 17 4.55 tV i 1,320 88 16,200 5,400 20,600 66 18 4 62 4 17 4.76 16 i 2 1,212 81 16,300 5,400 21,700 72 16 4, 140 3 15 5.77 ) 6 1 2 1.689 113 16,100 5,650 21,750 72 16 4 92 34 15 5 3 _1_ 1 6 1 2 1,352 90 16,375 5,650 22,025 72 16 4 76 4 15 5 83 JL- 1 6 1 2 1,296 86 16,270 5,650 21,920 72 17 4 140 3 16 5 77 1 6 1 2 1,799 120 16,725 5,650 22,375 72 17 4 92 34 16 5.3 JL- 1 6 1 2 1,440 96 17,000 5,650 22.650 72 17 4 76 4 16 5.83 -1. 1 6 1 2 1 380 92 16,895 5,650 22,545 72 18 4 140 3 17 5.77 .1. 1 6 1 2 1,909 128 17,450 5,650 23,100 72 18 4 92 34 17 53 JL. 1 6 2 1,528 102 17,725 5,650 23,375 72 18 4 76 4 17 5 83 _2_ l 6 1 2 1,464 98 17,620 5,650 23,270 72 19 4 92 34 18 5 3 .2. 1 6 1 2 1,615 10S 18,750 5,650 24,400 72 20 4 92 34 19 5.3 .1. 16 1 2 1,703 103 19,680' 5,650 25,330 72 21 4 92 34 20 5.3 -1_ 1 6 1 2 1,790 119 20,580 5,650 26,234 These horizontal return tubular boilers have the same dimen- sions, whether they are set with overhanging fronts or flush fronts, and the table may be used indiscriminately for either. The heating surface given in the table is the area which is directly exposed to the heat of the products of combustion; that is, THE SCHOOL HOUSE. 83 the exterior surface, in the case of the shell and heads, and the interior surface in the case of the tubes. The rated horse-power given is based upon 15 square feet of heating surface per horse-power. With the draft of a good chimney 80 feet high and proper flue connections, the rated capacity can easily be produced under work- ing conditions with good coal, it being understood that a horse- power refers to the evaporation of 344 pounds of water per hour from and at 212° F. (A.S.M.E. standard). Beyond the rating stated there is a surplus capacity of at least one-third when the full draft of the chimney is on and the fire is urged. With high chimneys and the best grade of bituminous coal the boilers can be worked to much higher capacities than those noted in the table. The thickness of boiler plates within ordinary use makes but little difference in the ability of the plate to conduct heat. A coating or incrustation on the plates and tubes makes consid- erable difference in the efficiency and life of a boiler and should be carefully guarded against. This is a matter that is often badly neglected by janitors in school buildings. The setting of a boiler is a matter to be carefully attended to in order that cracks may not appear and allow air to enter and cool the temperature of the fire and gases in the furnace. In setting a boiler on marshy or filled ground especial care should be taken to secure a good foundation, and in some cases a thick foundation of good concrete should be put under the whole apparatus to prevent unequal settling and cracking of the walls. Before a boiler is set the nature of the ground should be carefully investigated. In setting the fire-brick in a furnace they should be laid with but a small quantity of fire-clay between them, but sufficient to level the work. 84: THE SCHOOL HOUSE. TABLE 12. {Hodge Boiler Works, East Boston, A/ass.) DIMENSIONS RELATING TO BRICK SETTING FOR HORIZON- TAL RETURN TUBULAR BOILERS; NUMBER OF BRICKS GIVEN BEING APPROXIMATE. Ft. In. Ft. In. Ft. In. Ft. In. Ft. In. Ft. In. Diameter of shell 42 48 54 60 66 72 Length of shell over all 13 3 15 3 16 3 16 3 17 4 17 4 Length of brick setting over all with overhang- ing fronts 15 3 17 6 18 6 18 6 19 7 19 7 Length of brick setting over all with flush fronts 16 6 18 9 19 9 19 9 20 10 20 10 Width of brick setting for single boiler 7 7 8 1 8 7 9 1 9 7 10 1 Increase in width of set- ting for each additional boiler in a battery 5 11 6 5 6 11 7 5 7 11 8 5 Length of grate 3 6 4 4 6 5 5 6 6 Width of grate 3 6 4' 4 6 5 5 6 6 Vertical distance from floor to shell 3 9 3 9 4 4 4 4 Vertical distance from , grate to shell at front end 22 22 24 24 24 24 Vertical distance from floor to top of brick work 7 7 8 1 8 10 9 4 9 10 10 4 Number of red brick re- quired for setting single boiler overhanging front 11,923 14,563 16,819 17,977 20,048 21,359 Flush front 12,860 15,568 17,903 19,110 21,245 22,624 Number of fire brick re- quired for a single boiler 765 884 1,059 1,179 1,359 1,526 Number of red brick re- quired for each addi- tional boiler of a battery overhanging front 7,757 9,550 11,022 12,065 13,361 14,323 Flush front 8,335 10,174 11,695 12,773 14,109 15,116 Number of fire brick for each additional boiler of a battery 765 884 1,059 1,179 1,359 1,526 Number of red brick re- quired for each addi- tional length of one foot in the length of a single boiler 703 754 813 850 898 949 Number of red brick re- quired for each addi- tional length of one foot in the length of each additional boiler 434 46S 505 531 561 595 NOTE. — When the thickness of the inside walls is 8 inches, instead of 12 inches, to which the above table applies, the number of red brick required for the various sizes of boilers given is as follows: THE SCHOOL HOUSE. TABLE 13. Single boiler, overhang- ) ing front. J Single boiler, flush front Each additional boiler, \ overhanging front J Each additional boiler, flush front 10,14G 12,534 14,429 15,327 17,392 10,962 13,412 15,383 16,331 18,458 5,751 7,189 8,315 8,879 10,238 6,281 7,75'J 8,925 9,529 10,928 18,585 W,713 11,084 11,814 Smoke Flies for Steam-Boilers. The smoke flues connecting steam-boilers to the chimney should be constructed of iron; brick ones do not prove satisfactory. In most smoke-flue work No. 12 tank iron is used unless other- wise specified. The two kinds generally used are those of circular cross-section and those of a rectangular shape. The seams of circular flues are lap riveted, and the rectangular ones are joined together at the corners by angle irons, and where the flue is of considerable width it is stiffened by the same means. The short branch flue which connects immediately to the boiler (the uptake in a horizontal boiler) is provided with a clamper. The main flue between the last boiler and the chimney is fitted with a regulating damper for controlling the entire battery of boilers. The size of the flue should be equal to the collective area of the tube openings in all the boilers to which it is connected. A clean-out which can be closed air-tight should be provided. Flues should be as short and straight as practicable, and where a change of direction is made it should be by a curve rather than a sharp or square angle. Rules for Determining Pressure a Boiler will Sustain : United States Governme?tt Standard. Divide tensile strength of metal by 6 and multiply by thickness of stock. Divide product by radius of boiler in inches. The quotient is the steam pressure the boiler will sustain. Massachusetts hispcctors' Rule. Multiply the thickness of sheet by tensile strength. Multiply this product by 56 per cent if single riveted, or by 70 per cent if double riveted; by 80 or 85 per cent if butt-strap riveted. The quotient is the bursting pressure. For safe pressure divide burst- ing pressure by 4£ or 5, according to the condition of the boiler. 86 THE SCHOOL HOUSE. Water-tub^ Boilers. Water-tube boilers are boilers in which the water is inside the tubes and the heat is applied from the outside, instead of having the water on the outside and the heat inside the tubes, as in hori- zontal or upright boilers. This class of boilers is used to a limited extent in scboolhouses in Massachusetts ; generally where a mechanical (fan) system of heating and ventilation has been installed, or where the architect has not provided a boiler-room of sufficient size. They generate steam quickly and can be forced when under the charge of a skilful engineer, and have given good results, especially where a fan is used ; but for ordinary small or moderate size school- houses the return tubular class is to be preferred. Upright Tubular Boilers. Upright tubular boilers have been used in schoolhouses ; but to a limited extent and where it has been desired to run an engine at high pressure to drive a fan or blower. They occupy but little floor space, but in the ordinary school- house basement require that a pit be provided to keep the top of the boiler sufficiently below the ceiling. It is generally better to use a low-pressure engine having a cylinder of large diameter and short stroke, rather than to install a high-pressure engine driven by steam at high pressure from an upright boiler. Cast-Iron Sectional Boilers. Cast-iron sectional boilers have been used to a considerable extent in schoolhouses, but the results obtained are not in the majority of cases as satisfactory as when the return horizontal tubular class are used. , There are many different patterns : good, indifferent and bad. Different manufacturers claim their design to be the best, and to describe them all would be beyond the scope of this book. In many cases a higher rating for efficiency is given in catalogues than is shown in the actual work performed. If the designer of the heating system in a schoolhouse depends upon the catalogue rating of many of this class of boilers, he will be sadly disappointed in the final test. A large factor of safety should be allowed for rating many of this class of boilers. In installing them in schoolhouses it is well to obtain from the manufacturer a good and sufficient guarantee that the boiler will do the work required. THE SCHOOL HOUSE. 87 Manv of this class have a large amount of heating surface and a small amount of water and steam space, and when forced the water is carried into the heating coils or radiators and trouble is caused by low water in the boiler, melting out the fusible plug and cracking sections of the boiler. The writer has seen many cases where this has occurred and caused the shutting down of the heating apparatus. This has been particularly noticeable in the small cast-iron sectional boilers so generally used for heating the vent shafts and for supplying direct radiation in corridors, teachers' rooms, etc., in school - houses. Where this class of boilers is used care should be taken to select a boiler of ample size to do the work required, and one that has a proper proportion of heating surface to the water and steam space; also one that does not have a large, flat, unstayed heating surface. REQUIREMENTS OF BOILER INSPECTION DEPARTMENT OF MASSACHUSETTS DISTRICT POLICE AS TO FITTINGS FOR LOW-PRESSURE HEATING BOILERS. Upon all steam boilers used for heating purposes, having a grate area of over two square feet, and subject to inspection by this department, the fol- lowing fittings must be provided, being deemed necessary for safety. One safety-valve on each boiler with no obstruction between valve and boiler. If pressure carried is to be below 25 pounds, the least area of the safety-valve in inches is to be reckoned by dividing the area of grate in square feet by 2£ if a pop valve is used, or by two if a lever, dead- weight, or simple spring valve is used. One steam gauge on each boiler, connected with syphon or equivalent device between gauge and boiler, to fill gauge spring with water. The supply pipe is to come from steam space of boiler. Each boiler must have at least two try-clocks, the lower one to be placed 24 inches above fusible plug or lowest safe water line. Where a glass is also used the lower end of glass must be above the fusible plug or lowest safe water line. Each boiler must be provided with stop valve on main steam pipe leading from boiler. Each boiler must have check valve and stop valve on main return pipe. Where a damper regulator is used, the pressure supply pipe must be taken from the steam space of the boiler, with proper water syphon. SAFETY-VALVES FOR HIGH PRESSURE. If pressure carried is between 25 and 100 pounds, the area of safety-valve in inches shall equal the area of grate in square feet divided by 3, for lever cr dead-weight valves, and by 'Ah for pop valves If pressure is above 100 pounds, divide by 5 for pop valves and by 4 for lever or dead-weight valves. 88 THE SCHOOL HOUSE. SECTIONS 78 TO 86 INCLUSIVE OF CHAPTER' 102 OF THE REVISED LAWS OF MASSACHUSETTS, RELATIVE TO THE LICENSING OF ENGINEERS AND FIREMEN. As Amended by Chapter 310, Acts of 1905. Section 78. No person shall have charge of or operate a steam boiler or engine in this Commonwealth, except boilers and engines upon locomotives, motor road vehicles, boilers in private residences, boilers in apartment houses of less than five flats, boilers under the jurisdiction of the United States, boilers used for agricultural purposes exclusively, boilers of less than eight horse power, and boilers used for heating purposes exclusively which are provided with a device approved by the chief of the district police limiting the pressure carried to fifteen pounds to the square inch, unless he holds a license as hereinafter provided. The owner or user of a steam boiler or engine, other than boilers or engines above excepted, shall not operate or cause to be operated a steam boiler or engine for a period of more than one week, unless the person in charge of and operating it is duly licensed. Section 79. If such steam engine or boiler is found to be in charge of or operated by a person who is not a duly licensed engineer or fireman and, after a lapse of one week from such time, it is again found to be operated by a person who is not duly licensed, it shall be deemed prima facie evidence of a violation of the provisions of the preceding section. Section 80. The words "have charge" or "in charge," in the two preceding sections, shall designate the person under whose supervision a boiler or engine is operated. The person operating shall be understood to mean any and all persons who are actually engaged in generating steam in a power boiler. Section 81. Whoever desires to act as engineer or fireman shall apply for a license therefor to the examiner of engineers for the city or town in which he resides or is employed, upon blanks to be furnished by the examiner. The application shall be accompanied by a fee of one dollar and shall show his total experience. Wilful falsification in the matter of state- ments contained in the application shall be deemed sufficient cause for the revocation of said license at any time. The applicant shall be given a practical examination and, if found competent and trustworthy, he shall receive, within six days after the examination, a license graded according to the merits of his examination, irrespective of the grade of license for which he applies. The applicant shall have the privilege of having one person present during his examination, who shall take no part in the same, but who may take notes if he so desires. No person shall be entitled to receive more than one examination within ninety days, except in the case of an appeal as hereinafter provided. A license shall continue in force for three years, or until it is revoked for the incompetence or untrustworthiness of the- licensee ; and a license shall remain revoked until a new license is granted. A license, unless revoked, shall be renewed by an examiner of engineers upon application and without examination, if the application for renewal is made within six months after its expiration. If a new license of a different grade is issued, the old license shall be destroyed in the presence of the examiner. If a license is lost by fire or other means,, a new license shall be issued in its THE SCHOOL HOUSE. 89 place, without re-examination of the licensee, upon satisfactory proof of such loss to an examiner. Section 82. Licenses shall be granted according to the competence of the applicant, and shall be distributed in the following classes : Engineers' licenses: — First class, to have charge of and operate any steam plant. Second class, to have charge of and operate a boiler or boilers, and to have charge of and operate engines, no one of which shall exceed one hundred and fifty horse power, or to operate a first-class plant under the engineer in direct charge of the plant. Third class, to have charge of and operate a boiler or boilers not exceeding in the aggregate one hundred and fifty horse- power, and an engine not exceeding fifty horse-power, or to operate a second-class plant under the engineer in direct charge of the plant Fourth class, to have charge of and operate hoisting and portable engines and boilers. Firemen's licenses: — Extra first class, to have charge of and operate any boiler or boilers. First class, to operate any boiler or boilers. Second class, to have charge of and operate any boiler or boilers where the pressure carried does not exceed twenty-five pounds to the square inch, or to operate high pressure boilers under the engineer or fireman in direct charge thereof. A person holding an extra-first or first-class fireman's license may operate a third-class plant under the engineer in direct charge of the plant A person who desires to have charge of or to operate a particular steam plant or type of plant may, if he files with his application a written request signed by the owner or user of said plant for such examination, be examined as to his competence for such service and no other, and if found competent and trustworthy shall be granted a license for such service and no other. Section 83. The horse-power of a boiler shall be ascertained upon the basis of three horse-power for each square foot of grate surface, for a power boiler, and on the basis of one and one-half horse-power for each square foot of grate surface, if the boiler is used for heating purposes exclusively. The engine power shall be reckoned upon a basis of a mean effective pressure of forty pounds per square inch of piston for a simple engine; fifty pounds for a condensing engine; and seventy pounds for a compound engine, reckoned upon area of high-pressure piston. Section 84. A person who is aggrieved with the action of an examiner in refusing or revoking a license may, within one month .after his decision, appeal therefrom to the remaining examiners, who shall together act as a board of appeal, and a majority of whom shall have the power to hear the parties and pass upon the subjects of appeal. The applicant may have the privilege of having one first-class engineer present during the hearing of his appeal, but he shall take no part therein. The decision of the majority of such remaining examiners so acting shall be final if approved by the chief of the district police Section 85. An engineer's or fireman's license, granted under the provisions of the seven preceding sections or the corresponding provisions of earlier laws, shall be placed so as to be easily read in a conspicuous place in the engine room or boiler room of the plant operated by the holder of such license. Section 86. The boiler inspection department of the district police shall act as examiners and enforce the provisions of the eight preceding sections 90 THE SCHOOL HOUSE. and whoever violates any of the provisions of said sections shall be punished by a fine of not less than ten nor more than three hundred dollars or by imprisonment for not more than three months. A trial justice shall have jurisdiction of complaints for violations of the provisions of the eight preceding sections, and in such cases, may impose a fine of not more than fifty dollars. All members of the boiler inspection department of the district police shall have authority in the pursuance of their duty to enter any premises on which a boiler or engine is situated, and any person who hinders or prevents or attempts to prevent any state boiler inspector from so entering shall be liable to the penalty as specified in this section. [Chap. 310, Acts of 1905.] ********* Section 4. All acts and parts of acts inconsistent herewith are hereby repealed : provided, however, that this act shall not apply to the exemptions specified in section seventy-eight of chapter one hundred and two of the Revised Laws or that such repeal shall not invalidate any license granted under the acts repealed; and licensees holding licenses so granted shall have the powers given to licensees of the same class by section two of this act. Section 5. This act shall take effect on the first day of July in the year nineteen hundred and five. {Approved April 20, 1903. ] [Amendment of 1905.] [Chap. 472, Acts of 1905.] An Act relative to the inspection of steam boilers. Be it enacted, etc., as follows : Section 1. All steam boilers of more than three horse power, except boilers upon locomotives, in private residences, or under the jurisdiction of the United States, or boilers used exclusively for agricultural, horticultural or creamery purposes, shall be inspected either by the district police or by an insurance company authorized to insure boilers within the Common- wealth. Such inspection shall be made internally and externally at least once in each year. The owner or user of any steam boiler inspected by the district police shall pay to the inspector the sum of five dollars at each internal, and two dollars for each external, inspection for every boiler so inspected. Section 2. Every insurance company shall forward to the chief of the district police within fourteen days after each internal and external inspection a report of every boiler so inspected by it. Such reports shall be made on blanks furnished by the chief of the district police, and shall contain any recommendations that the insurance company may think it desirable to make. Notice shall be given by the insurance company or the inspector to the owner or user of the boiler inspected of the pressure at which the boiler may safely be operated. Section 3. Any insurance company failing to make a report as above provided shall be fined not more than five hundred dollars for every such failure. Any owner failing to comply with the requirements of the insur- ance company inspecting his boiler, after notice by the chief of the district police, shall be liable to a fine of not more than five hundred dollars for such failure, and the use of said boiler may be enjoined in the manner THE SCHOOL HOUSE. 91 provided in section four of chapter one hundred and five of the Revised Laws. The district police shall have authority in the discharge of their duty to enter upon any premises where steam boilers are located, for the purpose of enforcing the provisions of this act Section 4. All acts and parts of acts inconsistent herewith are hereby repealed. [Approved May 26, /goj.] REVISED LAWS OF MASSACHUSETTS. Chapter 105. Of the Inspection of Steam Boilers. Section 1. The chief of the district police shall detail ten members of the inspection department of the district police, who, under his direction, shall inspect stationary steam boilers and their appurtenances, shall act as examiners of engineers and firemen and shall report to said chief. Section 2. Whoever owns or uses or causes to be used a steam boiler, except boilers upon locomotives, in private residences, under the jurisdiction of the United States or under the periodically guaranteed inspection of com- panies which have complied with the laws of this Commonwealth, boilers used exclusively for agricultural, horticultural and creamery purposes or boilers of less than three horse power, shall annually report to the chief of the district police the location of such steam boiler. Section 3. Each boiler designated in the preceding section and not therein excepted shall be inspected by the inspector of boilers for the district in which said boiler is located, and if he so orders the owner or user shall have the boiler blown off dry and the man-hole and hand-hole covers thereon removed, ready for inspection, upon the day designated by the inspector, who shall give the owner or user of said boiler fourteen days notice in writing of the day upon which he will make such internal inspection, which shall not be required oftener than twice a year Section 4. If, upon examination, said inspector finds the boiler to be worthy and in safe working order, with the fittings necessary to safety, and properly set up, he shall grant to the owner or user thereof a certificate of inspection, and thereupon said owner or user may use the boiler mentioned in the certificate. If the inspector finds that the boiler is not in safe con- dition, or is not provided with fittings necessary to safety or with fittings not properly arranged, he shall withhold his certificate until the boiler and fittings are put into condition satisfactory to him ; and the owner or user shall not operate such steam boiler or cause it to be operated until such certificate has been granted. The owner or user of such boiler shall pay to the inspector at each inspection two dollars for each boiler inspected. The supreme judi- cial court or the superior court, upon the application of the inspector of boilers approved by the chief of the district police, shall have jurisdiction in equity to restrain the owner or user of such boiler from operating it without certificate. Section 5. If the inspector finds that the owner or user of a steam boiler is putting too much pressure upon it, he may fix the maximum pres- sure to be carried by it and shall prescribe a device to prevent it from carry- ing more than the maximum pressure designated, which shall be approved by the chief of the district police and which the owner or user shall place or cause to be placed upon said boiler. No person shall in any manner tamper 92 THE SCHOOL HOUSE. with such device, or load the safety-valve to a greater pressure than that allowed by the inspector. Section 6. Whoever violates the provisions of the preceding sections of this chapter shall be punished by a fine of not more than five hundred dollars or by imprisonment for not more than six months, or by both such fine and imprisonment. Section 7. The mayor and aldermen of any city except Boston, or the selectmen of a town, or any person by them authorized, may, after notice to the parties interested, examine any steam engine or steam boiler therein, whether fixed or portable ; and for that purpose may enter any house, shop or building ; and if upon such examination it appears probable that the use of such engine or boiler is unsafe, they may issue a temporary order to suspend such use ; and if, after giving the parties interested, so far as known ; an opportunity to be heard, they adjudge such engine or boiler to be unsafe or defective or unfit to be used, they may pass a permanent order prohibiting the use thereof until it is tendered safe. If, after notice to the owner or person having charge thereof, such engine or boiler is used contrary to either of such orders, it shall be deemed a common nuisance, without any other proof thereof than its use. Section 8. The mayor and aldermen and selectmen may abate and remove a steam engine or steam boiler which has been erected or used con- trary to the provisions of the preceding section in the same manner as boards of health may remove nuisances under the provisions of sections sixty-seven, sixty-eight and sixty-nine of chapter seventy-five. Section 9. No person shall manufacture, set up or use a steam boiler or cause it to be used unless it is provided with a fusible safety plug, made of lead or some other equally fusible material and of a diameter of not less than one-half an inch, placed in the roof of the fire box, if a fire box is used, and in all cases, in a part of the boiler fully exposed to the action of the fire, and as near the top of the water line as any part of the fire surface of the boiler. Section 10. Whoever, without just and proper cause, removes the safety plug from a boiler or substitutes therefor any material more capable of resisting the action of the fire than the plug so removed shall be punished by a fine of not more than one thousand dollars. Section 1 1 . Whoever manufactures, sets up or knowingly uses or causes to be used for six consecutive days a steam boiler, unprovided with a safety fusible plug as described in section nine, shall be punished by a fine of not more than one thousand dollars. Section 12. The provisions of the five preceding sections shall not apply to a boiler for which a certificate of inspection issued under the provi- sions of sections four and five is in force CHAPTER VI. STEAM-PIPES THE success of a steam-heating apparatus will to a consid- erable extent depend upon the proper size, location, grading, dripping and valving of the steam-pipes. In the earlier installment of gravity syste'ms of steam-heating in schoolhouses trouble was often caused by the use of too small pipes, both for supply and return. At the present time larger pipes are used and much better results are obtained. In piping indirect radiators the following may be considered a safe rule for size of supply and return pipes when a gravity system is used and steam supplied at low pressure, five pounds or less. TABLE 14. Square Feet of Indirect Radiators. Supply. In Inches. Return. In Inches. 30 or less 30 to 50 50 to H)0 100 to 160 1 H U 2 1 1 H H It is not advisable to make indirect radiator stacks with more than 160 square feet of radiating surface, and 140 is to be preferred to 160 if good circulation is expected. Three-quarter-inch pipe is the smallest that should be used for return, even from very small radiators. For indirect steam-heating the supplv pipes should have double the area in cross section of those supplying direct radiators. For direct radiation steam mains and risers the rule adopted by many heating contractors is T 1 -^ the square root of the heating sur- face in square feet for the diameter of the supply pipes in inches ; or, square the diameter of the pipe in inches for the number of hundred feet of direct radiation it will supply. By using pipe one size larger than that called for by these rules better results will be obtained. Another rule is to divide the amount of direct heating surface in square feet by 100, divide the quotient by .7854, then extract the square root of the quotient ; the result will be the diameter of the pipe in inches. 94 THE SCHOOL HOUSE. As a general rule, return pipes should be one size smaller than the supply pipes, but with large supply mains this may be consid- erably reduced. By using large and well-covered pipes satisfactory results will be obtained. Too frequently, in order to reduce the cost, pipes of too small diameter are used, especially for indirect steam heating. The supply pipes in the basement of a schoolhouse should be well covered with a neat non-heat-conducting covering, and although the first cost will be increased, yet the results therefrom will fully compensate for the additional expense. Care should be taken that the steam-pipes are properly pitched, dripped and valved in order to secure free and noiseless circulation and return ; that they are properly supported on roller pipe hangers and proper allowance made for expansion and contraction. The main return pipes should be provided with proper check valves and shut-off s. Valves for controlling vent-flue heating should be placed in the basement. Every radiator, heating coil or stack should be fitted with a supply valve, return valve and automatic air valve properly located. Gate or angle valves are to be preferred to globe valves. Overhead pipes for heating the basement should be properly valved, pitched and of such form as to provide for expan- sion and contraction, and hung from the floor timbers of the first story with securely fastened roller pipe hangers about every eight feet. Where circulation pipes are placed on the walls the pipes should be well straightened and secured to the wall by hook and expansion plates, fastened to wooden strips placed not more than ten feet apart, and ample provision made for expansion and con- traction. Rising main and return pipes should be straight and parallel, properly valved and dripped, and where pipes pass through floors they should be incased through the full depth of flooring and ceiling in tin tubes with Jlanged iron plates screwed to the floor, and with iron ring plates or flanges securely fastened to the ceiling. Where pipes pass through wooden partitions tin sleeves and flanged plates should be used and if through brick walls, metal collars should be provided. Where practicable, return pipes should be laid in a properly-graded brick trench having a covering of cast-iron plates or bluestone flagging. Where several vertical return pipes enter the main return they should in all cases be carried well below the water-line in the boiler before they unite into one pipe. THE SCHOOL HOUSE. 95 By proper arrangement of pipes and radiators in a low-pressure gravity return system the condensation may be easily and noise- lessly returned to the boiler without the use of traps or pumps. For piping connections it is advisable to use eccentric fittings. A two-pipe, low-pressure, gravity return system of steam- heating is to be preferred for schoolhouses of small or moderate size. In large buildings a double mechanical system (one having a fan supply and fan exhaust), or a combination of fan (or plenum) supply and gravity exhaust, is to be preferred. Where a mechanical system is used, the exhaust from the engine should also be used for heating. A mechanical system will require the use of fans, engine, pumps or traps, governor, tanks, steam separator, reducing valves, exhaust head, vapor pipe, etc. A blow-off tank, properly connected with a dry well or sewer and properly trapped, should be provided in all cases where practicable. A valve or cock should be provided at the lowest place in the system to draw off the water when desired. Radiators. In the earlier attempts to ventilate school buildings by indirect radiation many failures occurred on account of an insufficient amount of radiation and improperly locating and casing it ; not allowing sufficient space between the sections for a liberal quantity of air to pass, too small steam supply and return pipes, and not providing adequate means for regulating the temperature of air passing the radiators. It has been found in actual practice (and the schoolrooms in Massachusetts are now generally heated accordingly) that to secure the best results under varying conditions of temperature and wind 400 square feet of cast-iron radiating surface should be supplied for an ordinary schoolroom 28 by 32 by 12 feet, if situated where there are two cold exposed walls and where ample window space to give good light is provided. This should be divided into three stacks, one of 100, one of 140 and one of 160 square feet; or one of 120 and two of 140 square feet each, each stack to be separately piped and valved, in order that one, two or three sections may be used as needed, according to the outside temperature. The 100 feet section should be placed nearest the uptake warm-air flue. Where there is but one exposed wall, and on the southerly side, 380 square feet may be used and divided into three stacks, one of 100 and two of 140 square feet each. 96 THE SCHOOL HOUSE. Cast-iron radiators having an extended surface, and with not less than one-half-inch space between the ends of the pins or ribs of the several sections, are now generally used in Massachusetts school- houses. While coils or radiators made of steam-pipes are the most efficient radiating surfaces, yet, on account of the cost and the facility of constructing the indirect radiator stacks, cast-iron is now generally used with gravity systems. It is better to use a deep radiator than to double bank or place one section above another. Cast-iron extended surface radiators having 20 square feet of radiating surface per section give very satisfactory results. The sections are 36 inches long, 15^ inches high, and connected four inches from center to center of the sections, tapped for. two- inch supply and return pipes, and have right and left nipple connec- tions. The air-valve measures f of an inch. When more than one school-room receives its warm air through radiators in the same cold-air room the radiator stacks for each room should be separated by galvanized-iron divisions extending about 20 inches below the bottom of the stacks. Where this is not done, and two or more rooms receive air from the same cold-air room, the results are very unsatisfactory, as one room may receive much more than its fair proportion of heat and air at the expense of another. The galvanized-iron casings for indirect radiators should be made on number 20 or 22 gauge iron, and be well stiffened at the edges and corners. When rooms in different stories of the building receive their air supply from the same cold-air room the radiators for the first story should be placed nearest the cold-air window, in order that they may have an advantage in receiving air in preference to the rooms in the second or third stories. The supply and return pipes for the indirect radiators should be well protected in all cases where they come inside the cold-air rooms with first-class pipe covering. <• The valves should always be placed outside the cold-air rooms. The air-valves give better results when placed in the quarter turn or elbow where the return changes to a downward direction than when placed in the radiator itself, as is usually done where direct radiators are used. The bottom of the radiators should not be cased, but left entirely open, as much more even distribution of air is obtained. THE SCHOOL HOUSE. 97 In the earlier indirect radiator work it was customary to inclose the radiators on all sides and bring the air in at one end of the bottom of the casing, taking it out at the top of the opposite end. This does not give as good results, or utilize the whole of the radiator surface, as well as when the bottom is left entirely open and a cold-air room is provided. Under some conditions, when the first method is used, there is a reversed or back draft, and the writer has frequently found warm air going out of the building through what was intended to be the cold-air supply opening. There are many patterns of direct radiators in use, each of which is claimed by the manufacturer to have various good points. Better results are obtained when a tall radiator is used than when the stack is made long and low. In Part II. is shown a direct-indirect radiator, designed by the late John T. White, which has been successfully used where a full supply of air is not required by indirect radiators. It is cased and inclosed in a manner that insures a better utilization of heat than is possible with the common style of direct-indirect radiators. In many schoolhouses lines of 1 ^-inch steam-pipe are placed on the outside walls of the rooms, and are used at night and before the school session opens to quickly warm the rooms. In rooms occupied but a part of the time, such as assembly halls and labora- tories, etc., this is a good provision and saves fuel, but they should not be used in schoolrooms while schools are in session. Direct radiators are often used to good advantage in schoolhouse corridors and in teachers' rooms. In basement rooms the heating should be by overhead lines of 1^ inch pipe, unless a room is used as a manual training room or for a similar purpose, in wdiich case a moderate supply of air from indirect radiators can be introduced near the ceiling. In using wall or ceiling pipes special attention should be given to properly provide for expansion and contraction. There should be at least two feet distance between the bottom of the radiators and the water-line in the boiler to secure a good return of the condensation from the radiators. If a greater distance can be had it will be better, and danger of filling the radiators with water will in a great measure be prevented. The writer has seen cases where an otherwise well-designed system of heating has been spoiled by not allowing sufficient distance between the bottom of the radiators and the water-line in the boiler. A method is shown in Part II. of arranging radiators to be used as foot-warmers and for warming the corridors. These stacks are 98 THE SCHOOL HOUSE. usually made up of 120 square feet of cast-iron extended surface ra- diators, cased in galvanized iron and hung from the basement ceiling. Very satisfactory results are obtained when two lines of 1^ inch steam-pipe are placed near the floor in the corridor and under the clothing racks. An Approximate Rule for Estimating the Amount of Indirect Radiation For a fifty-seat schoolroom of the ordinary size (28 by 32 by 12 feet) with a gravity system of heating and ventilation, using a good indii*ect radiator with ample flues, etc., and natural draft, is as follows : 50 (number of pupils) X 30 (cubic feet of air per pupil per minute) = 1500 (cubic feet of air per minute). 1500 (cubic feet per minute) X 60 (minutes per hour) =90,000 cubic feet of air supplied per hour. Air at zero to be warmed 105 degrees F. 90,000 (cubic feet) X 105 (degrees) =9,450,000 cubic feet of air warmed one degree. 9,450,000 (cubic feet) -r- 50 (cubic feet warmed one degree by one heat unit) = 189,000 heat units. 189,000 (heat units) -r- 1,000 (heat units available per pound of steam) =189 pounds of steam condensed to water. 189 X 2=378 square feet of radiation. In actual practice from 380 to 400 square feet of cast-iron indirect radiation is used per room. This allowance is made on account of overrating the square feet of surface in radiators by the manufac- turers, for air leakage in rooms and to meet the requirements in exceedingly cold weather. While this may not be an approved scientific method of calcu- lating indirect radiation, and may by some be called a " rule of thumb," yet in actual practice it has giveii excellent results and may be considered as safe as some more scientific and theoretical formulas. Automatic Heat Control. Systems of automatic heat control have been installed in a con- siderable number of schoolhouses, especially in large buildings, and if they can give the results claimed for them they will be of great service. Unfortunately, in many cases they have not proved satisfactory, and in a short time complaints were made that the expected results had not been obtained. The first attempts to automatically control mixing dampers were generally complete failures. A device that opens wide or closes THE SCHOOL HOUSE. 99 tight the mixing damper changes the temperature from all warm to all cold air, and uncomfortable drafts are the result. The writer has seen cases where the temperature of the incoming air was changed from over 100 degrees F. to less than 30 degrees F. in less than four minutes when the mixing damper was auto- matically operated. When the damper was again moved the temperature would rise to the high point in but little over five minutes. This was especially noticed when a strong wind was blowing into the cold-air room. When the mixing damper is moved to entirely shut off the warm air, except what little leaks through the narrow spaces on the sides and top of the mixing damper, the radiators, if steam is used, soon become cold, and the cold air from outside passes up directly into the schoolroom. With furnaces the results are not any more satisfactory. When the mixing damper is moved slowly by the automatic control, but is opened wide or fully closed, the results are not satisfactory. The managers and agents of some automatic heat-controlling systems frequently guarantee that the mixing-dampers or the valves controlling the heat supply steam-pipes will be operated by one degree or less change of temperature, as indicated by the ther- mometer attached to the thermostat. While this is true in many cases, yet it does not give satisfactory results at all times. When the cold air is admitted by the mixing-damper, or the steam-valves to the indirect radiators are shut, the radiators are soon cooled and uncomfortable drafts are felt, and as the thermostats are often placed where they are not easily and quickly acted on by the incoming air, the drafts continue. After the steam has been again turned on by opening the valves, time is required for the radiators to again become warm enough to give off sufficient heat to properly warm the incoming air, the cold drafts will continue until the incoming air has changed the temperature at the thermostat enough to operate the valve or damper-controll- ing device. This is often several minutes after the valves have been opened. Most of the automatic heat-controlling devices are of delicate construction, and the writer has seen cases where an accumulation of lint or fine fibers has caused the apparatus to become inoperative. Where automatic control has been used on direct radiators, or where a combination of automatic and hand-control has been used on the valves of different sections of the indirect radiators, more 100 THE SCHOOL HOUSE. satisfactory results have been obtained than when used on mixing- dampers. By dividing the amount of indirect radiation for a school-room into three sections and using hand valves on two, and automatic on one section, better results are obtained than where the automatic is used on all three sections. Automatic control is sometimes used on the supplementary radiation in mechanical systems where fans or blowers are used. If it is to be used in a mechanical system the results will be better if the primary coils or stacks are provided with all or nearly all band-controlled valves, and the automatic used on the supple- mentary coils or stacks or direct radiators or wall coils, if such are provided. When used on hot-water radiators the change of temperature is not as rapid as with steam radiators. CHAPTER VII. FURNACES. THE use of furnaces for heating and ventilating school buildings should be confined to small buildings not' exceeding eight rooms. In large buildings the number of furnaces required will occupy so much of the basement and there will be so many fires to attend to that a steam-heating apparatus can be more advantageously installed. When furnaces are used in school buildings or places of assem- blage they should be located where the warm-air flues or ducts will be as nearly perpendicular as possible. Long and nearly hori- zontal runs of pipe should be avoided. It is advisable that schoolhouse furnaces should be of heavy castings having as few joints as possible. There are several makes of furnaces specially designed for schoolhouse heating and of extra large size. A cast-iron furnace having a fire-pot of 34 to 35 inches diameter should be provided for two school-rooms of the ordinary size (28 by 32 by 12 feet). Attempts to use smaller furnaces or to heat more than two ordinary size school-rooms from one furnace have resulted in failures to give the required amount of heat, and now it is seldom that a contractor intending to do good work will attempt to heat and ventilate more than two schoolrooms with one furnace, even if the furnace is of the largest kind manufactured. In selecting a furnace, one with a nearly straight-sided fire-pot is to be preferred to one that has sloping or tapering sides. In the latter case the accumulation of ashes at the side of the fire-pot retards the passage of heat, and the fire is not as easily cleaned as when the sides are nearly perpendicular. Furnaces provided with triangular revolving grates are to be preferred to those having oscillating ones, as the triangular grates will cut the ashes and clinkers and remove them more effectually than will other patterns of grates. 102 THE SCHOOL HOUSE. Wrought -iron or steel-plate furnaces with fire-brick lining have not given as satisfactory results as those of cast-iron which have a good thickness of metal. It is claimed for wrought -iron furnaces that they do not allow gas t6 escape through the metal, and that it will through highly- heated cast-iron. While it is true that under some conditions gas will to a limited extent escape through highly-heated cast-iron, yet with an ample supply of air passing to the school-rooms and a large furnace of heavy castings, not overheated, the amount of gas escaping will be so very small that it may be practically disregarded. The escape of gas through heated cast-iron is more a matter of advertising the special advantages claimed for some furnaces than of real danger to the occupants of a school-room. It is essential, however, that there be as few pieces as practicable, and that the joints be made as tight as possible. By proper attention to the draft and check dampers the amount of escaping gas can be reduced to a point at which no ill effects can be observed. If it is suspected that gas is escaping from the combustion chamber into the warm-air supply for the room, an old rubber or a leather shoe may be thrown into the fire, and when the shoe is well ablaze, all the dampers and drafts being closed, it will soon be determined whether or not gas is passing into the room. The odor of the old shoe will be noticeable at the warm-air inlet if any considerable amount of gas is coming in. Several designs of cast-iron furnaces made of vertical sections with extended surfaces, and held together with bolts through flanges of the sections, have been used in school buildings ; but they are not a desirable type, as there are too many joints, some of which may warp and open up a passage for the unconsumed products of combustion to pass through and mingle with the air supply for the schoolrooms. This class of furnace is now seldom installed in Massachusetts schoolhouses. The writer has seen a number of these furnaces, which by exces- sive firing by the janitors have so warped at the flanges and where the bolts have so rusted or been destroyed by heat, that openings, sometimes one-half inch or more wide, have been made through which the unconsumed products of combustion have passed in a sufficient quantity to badly contaminate the air in the school-rooms. Some cast-iron furnaces also have a radiator attachment of thin sheet-iron or steel which in a few years will become corroded THE SCHOOL HOUSE. 103 sufficiently to open large holes for the escape of gas. Where these radiator attachments are used the sheet metal should he of sufficient thickness to last as long as the cast-iron fire-pot. In installing a furnace for schoolhouse heating special attention should be given to having sufficient space between the heating surface and the casing to allow the passage of a large quantity of air at a moderate temperature, rather than to heat a small quantity to a high temperature. It is advisable to use brick-set furnaces in schoolhouses instead of the metal-cased portable type generally used for dwelling-house heating, which usually have an insufficient space between the casing and the fire-pot. When the portable type of furnace is used in schoolhouses a special and large casing'should be provided. Smoke-pipes for furnaces should be of ample size and as short as possible to reach the chimney smoke-fine, having as few turns or elbows as practicable, and fitted with one or more dampers to regulate the draft. When soft coal is burned, the ordinary size schoolhouse-furnace smoke-pipe should be at least one inch larger diameter than when hard coal is used. Where it becomes necessary to take the smoke from two furnaces into one chimney flue, which is not a desirable arrangement, the pipes should be united by a breeches connection into one large pipe before it e'nters the chimney, anck each furnace smoke-pipe should have its own damper. A pit should be provided under the furnace which should be at least two feet deep and equal in width to the diameter of the furnace casing. This will allow the air to circulate around the fire- pot and will more effectively distribute it against the heated surface of the fire-pot. When, as has frequently been the case, the air is admitted through an opening in one side of the furnace casing and nearly opposite the fire-pot, the results are not satisfactory, and but part of the heated surface is utilized in the most effective manner. The air for mixing with the air from the furnaces for regulating the temperature of the school-room should never pass under the furnace, but should be entirely outside the space between the fire- pot and casing. When the air for mixing is taken under the furnace the result will surely be a failure to secure proper temperature for the air entering the school-room. The air will follow the line of least resistance, which is up near the heated surface of the fire-pot, and 104 THE SCHOOL HOUSE. will not pass under the furnace and into the space intended for it to reach the mixing-valve. When the warm air is shut off by the mixing-valve it will be heated and expanded in the hot-air chamber, and will back down and out into the space intended for the cold air for mixing. It will, when the mixing-valve is open for warm air, follow the line of least resistance, and the school-room will become overheated when there is a strong fire in the furnace. In moderate "weather under such conditions it will be impracticable to furnish the required amount of air without uncomfortably overheating the school-room. A furnace smoke-pipe should never pass through a cold-air room when possible to avoid doing so. In case of a smoke-pipe rusting and opening holes in the pipe, or if the pipe is not well and tightly jointed, there is liability of the unconsumed products of combustion passing into the school-rooms. The cold air also has a tendency to reduce the heat of the escaping gases and retard the draft. The writer has seen cases where the smoke-pipe was intention- ally twisted and made into "what may have been intended to be similar to a trombone coil, for the purpose, as alleged, of utilizing .the waste heat in the smoke-pipe for warming the air in the cold-air room. The result was, however, that it made a good condenser, and the condensed smoke and gases dripped down through the joints in the pipe into the cold-air room and assisted in contaminating the fresh air in addition to what was done by the gas escaping from the combustion chamber through openings between sections of the furnace. The condensation also assisted greatly to destroy the iron of the smoke-pipe. The furnace should be placed below the school-room rather than under a corridor or clothing room, in order that the warm air may pass up the front side of the heat shaft instead of on the back, and thus avoid uncomfortable drafts in the school-room. The cold air for mixing should always pass up on the rear side of the heat shaft. When for structural reasons the furnace must be placed other than under the school-room, the furnace should be placed low enough to enable the cold air for mixing to be taken over the top of the furnace casing or setting and to enter the heat shaft on the rear side. The proper location of the furnace is a matter that should be carefully considered, as nothing will contribute more to obtaining satisfactory results as to temperature than will its proper location with relation to the warm-air flues. THE SCHOOL HOUSE. 105 Pipes for conveying air to floor registers in corridors or clothing rooms should not be taken from the warm-air chamber of a furnace when the warm air for the school-rooms is taken into the room above the floor. Where this is done the results are not satisfactory as the air, instead of passing to the floor registers, will frequently be carried up the warm-air flues into the school-rooms, and a reversal of the air current will result. This will happen whenever the air supply for the furnace is checked or partly shut off at the cold-air opening into the fresh-air room. The air will be taken from the corridor or clothing-room to the school-room instead of from the furnace to the corridor. A liberal sized cold-air room should always be provided for furnaces in schoolhouses. It will to a great extent prevent back drafts by suction of the wind outside, and will give a much better supply of air under all conditions than will the ordinary cold-air box. The windows in the cold-air room should be hinged from the top and the opening be covered with a stout wire grill or netting. If heat is required for corridors or small rooms it is much better to provide a small and separate furnace for this purpose, providing steam cannot be used. In the best and most satisfactory work now being done in Massa- chusetts, where furnaces are used for heating class-rooms, a small steam boiler is used to furnish heat for the vent-flues and also for warming the corridors and small rooms. Twin connected furnaces are sometimes installed in schoolhouses ; but the results obtained are not as satisfactory as where each furnace has an independent setting. The distribution of air is not always good and depends upon which furnace is heated, as is the case when only one furnace is in use in moderate weather. When a fan is used and both furnaces are heated, the results are much better than by a gravity system using only one of the twin furnaces at a time. The use of a combination of furnace and hot-water heating is not recommended for schoolhouses. While often giving satisfac- tion in a dwelling-house, the conditions existing in a schoolhouse are not such as to justify the use of a hot-water attachment in the furnace. It frequently happens that during cold weather the janitor will allow the fires to go out between the close of the Friday p.m. session and the opening of the Monday a.m. session, or that during 106 THE SCHOOL HOUSE. the winter vacation the fires will not be kept up. In such cases the water attachment may become frozen and pipes or radiators burst. Where electric power is obtainable at a reasonable price a com- bination of fan and furnace may be used, and excellent results obtained, especially in mild weather. A good sized disk fan run at a comparatively low velocity, if properly located between the cold-air room and furnace, will give very satisfactory results and can quickly warm the building by rotating the air through it before the opening of the school session. Where electric power is not easily obtained a gas engine, and in some cases a water-motor, has been used to drive the fan. Neither of these is as satisfactory as electric power, especially in small buildings. The noise and the escape of the products of combustion into the building are serious objections to the use of a gas engine. The cost of water in cities and towns having a water supply system is such as to practically prohibit the use of the water-motors for running fans. Stack Heaters. When steam is not available for heating vent-flues, a stove or small furnace called a " stack-heater" is used to raise the tempera- ture in the vent-shaft and cause a good outflow of foul air. This stack-heater is usually placed in the basement so that it may be easily tended and to prevent the annoyance of ashes and dirt on the schoolroom floor. The air from the first story rooms is brought down in galvanized-iron ducts (or sometimes brick ducts) and enters the vent-shaft below the stack -heater. When a stack -heater is used the foul air from the schoolrooms is taken out through one common vent-shaft having a cross-sectional area of 20 square feet for four 50-seat schoolrooms, which are as many rooms as it is advisable to vent through one shaft. The two rooms in the second story should be vented directly into the common shaft. A stack-heater, having a fire-pot about 22 inches in diameter and grate 20 inches in diameter, is generally used to ventilate a school building where four school-rooms and two corridors are vented into the same shaft. A stack-heater for sanitary closets in school buildings containing up to eight rooms, and with a 16-inch diameter fire-pot and 14- inch grate, is commonly used in the sanitary vent-flues. While THE SCHOOL HOUSE. 107 smaller grate surface may theoretically be used in stack-heaters, yet with too small a fire-pot the fire is liable to go out for want of proper attention by the janitor. The stack-heater should be placed so that the air for furnishing the draft for the fuel is taken from outside the shaft. When the stack-heater is placed entirely within the vent-shaft and receives its air for draft from within the shaft and is tended through a door in the shaft, the results are not satisfactory. Where separate vent-flues are provided from each of several rooms it is not practicable to use a stack-heater, and steam heat must be employed. CHAPTER VIII. JANITORS. SUCCESS or failure in obtaining satisfactory results with a well-designed system of heating and ventilation often depends upon the care and good judgment exercised by the janitor or engineer having charge of the apparatus. Complaints have frequently been made that the heating and ventilation of a school building were not satisfactory; that the rooms were too warm or too cold ; that uncomfortable drafts were felt ; that the air was bad, etc. On inspection, these complaints were often well founded, and on looking for the cause it was very frequently discovered to be the fault of the engineer or janitor in charge, and not of the apparatus installed in the building. A janitor or engineer who is negligent, or not informed as to the proper way of operating the apparatus under his control, can easily give a well-designed and a properly-installed system a bad name. If heating and ventilating engineers and contractors who install systems in school and public buildings will see that the engineer or janitor is properly instructed as to his duties when first taking charge, they will find it greatly to their advantage ; not only as to the reputation their work will have, but they may be saved expense in responding to calls to come and see what is the matter with the apparatus. Printed instructions provided by the contractor or engineer who designed the work, if posted in the boiler or furnace-room, will more than pay the expense of printing and posting, and will save annoyance. A janitor who understands the system and properly manages it will not only give better satisfaction to the school authorities, but will in many cases make a considerable saving in the expense of operation. An incompetent or lazy janitor may cause an excessive waste of fuel and perhaps serious damage to the apparatus under his charge. THE SCHOOL HOUSE. 109 A janitor in a school or public building should be able to pass an examination as to his fitness and ability to manage the modern appliances for heating and ventilating a schoolhouse or public building. More is required of a janitor than the ability to shovel coal into a furnace or under a steam-boiler, or to see that a proper amount of water is in the boiler. Good judgment and a thorough knowl- edge of the apparatus is essential. Besides regulating the fires properly by having good and clean fires in cold weather and light fires in moderate weather, and, with a steam-heating system, seeing that the proper amount of radiation is in use, it is of the utmost importance that the inlets for fresh air, the mixing-damper for regulating the temperature of the air supplied to the class-rooms, the heat or fans for the ventilating ducts, and the dampers for regulating the outflow of foul air, should be properly understood and managed. In a mechanical (fan) system care should be taken that the fans are run at a proper speed and at the proper time. It is very important that the windows admitting air to the cold- air rooms, where the indirect radiators or furnaces are located, are properly opened or partly closed, as may be required by the con- stantly varying conditions of temperature and wind. These windows should be hinged at the top and open inward in order that the air may be deflected downward and distributed through the cold-air room. The stacks of indirect radiators or the furnace should never be placed so close to the window that the window cannot be opened to its full capacity. When a gravity system is used the windows in the cold-air rooms should have an opening equal to the combined area of the several ducts leading from the cold-air room. With a mechanical system in a large building the area of these windows may be less than in a gravity system. In mild weather and -when there is but little wind they should be kept wide open during the school session; in very cold or windy weather they should be partly closed ; but under no circumstances should they be entirely closed when school is in session . If opened too wide when a strong wind is blowing into the cold- air room, more air will be supplied than is required or can be properly warmed, and uncomfortable drafts will be felt in the school-rooms. 110 THE SCHOOL HOUSE. If closed too much, a sufficient supply of fresh air will not be furnished and the air in the school-rooms will be vitiated to an objectionable degree. When on the leeward side of the building they should be opened wider than when they are on the -windward side. Each window in the cold-air rooms should be provided with a stout cord or chain and pulley and means for fastening the same, in order that the window may easily be opened or closed to any desired position". It is also advisable to hold the window in the desired position and not allow it to fly up or down by the action of the wind. This can be done by another cord or chain. Mixing-valves or dampers are placed in the fresh-air ducts which lead to the several rooms, by means of which the air is allowed to pass through the stacks of indirect radiators or along the heating surface of the furnace, or is caused to by-pass without going through the heaters. By the use of mixing-dampers the temperature of the air supplied to the school-rooms can be regulated without materially reducing the supply. When valved registers are used and the room becomes too warm the heat is shut off as is also the supply of air at the same time. The teachers as well as the janitor frequently operate the mixing- valves and dampers, and should also be instructed in their use. It often happens that when the school-room becomes overheated the chain operating the mixing-valve is pulled in such a manner as to almost entirely shut off the warm air and turn on the cold air. Cold air is then admitted to the room and uncomfortable drafts are caused, then when the room has become too cool the chain is moved in the opposite direction and the room is soon overheated again. If this is continued the teacher or janitor will be kept busy trying to keep the room at a comfortable temperature. If, however, when the temperature of the room begins to rise or fall below the desired point (68 to 70 degrees F.) the mixing- damper chain is moved but a little at a time — say from one-half to one inch — there will be little difficulty in maintaining the desired temperature if the fires and the windows in the cold-air rooms are properly managed. The mixing-valve, after having been once properly adjusted, may not require to be moved during the whole or greater part of the session. Two or three pieces of thin or narrow ribbon — about one- quarter of an inch wide and about ten inches long (red, white and THE SCHOOL HOUSE. Ill blue would be appropriate colors) tied into the wire grill at the warm-air inlet, about two-thirds the distance up from the bottom to the top and in the center of the wire grill, will be of great assis- tance to the teacher in determining whether or not a proper amount of fresh air is being supplied to the school-room. If the ribbon does not blow out or flutter it will indicate a defi- ciency in the fresh-air supply. A metallic thermometer about four inches in diameter, which has an indicator hand, will, if placed on or in the wire grill near the ribbon, enable the teacher or janitor to place the mixing-valve in the right position. As the outflow of air from a room through the exhaust flues or ducts is caused, in a gravity system, by the difference between the temperature of the external and internal air, and also by the force of the wind blowing across the top of the ventilating stack or flue, some means of meeting the constantly-varying conditions of tem- perature and wind must be provided. In a mechanical system provision should be made for regulating the flow of air through the several ducts and flues. In both the gravity and mechanical systems dampers should be placed at the outlet from each ventilated room. The heat in the vent-flues should be used in a manner directly opposite from that used for warming the rooms. The greater the difference between the temperature of the outside and inside air, the less will be the amount of heat required in the vent-flues. In very cold and windy weather no heat may be needed in the vent-flues, and the dampers in the outlets from the rooms may often be partly but never entirely closed while school is in session. In mild and calm weather the dampers should be wide open and heat maintained in the vent-flue heaters. The warmer the weather, the more heat will there be required in the vent-flue heaters. Pieces of ribbon similar to those on the warm-air inlet should be provided for the outlets, but they should be placed on the inner side of the grill. If they flutter into the duct it will indicate an outflow of air from the room. If they blow back or rest 'against the grill it w r ill indicate a reversed draft or no draft. In cold weather, after the school session has closed, sufficient time should be allowed to flush out the room with fresh air. The dampers at the outlets should then be closed and the heat in the vent-ducts shut off. Leaving the dampers in the vent-ducts open at night will cause a waste of fuel and unnecessary cooling of the rooms. 112 THE SCHOOL HOUSE. In warm weather, when no heat is supplied by the warm-air inlets, the dampers may remain open at night. After school has been dismissed for the day and the class-rooms have been flushed out with fresh air from the warm-air inlets the windows admitting air to the cold-air rooms in the basement should be closed, as should also the dampers in the vent-flues. The rotat- ing registers in the floor above the cold-air rooms, as "well as the doors from the several class-rooms, should then be opened and the air rotated through the building by means of the indirect radiators or furnaces. The fires can then be banked and checked for the night. In cold weather, if direct radiation has been provided in the class-rooms in addition to the indirect radiation, the direct radiation should be turned on and kept on till a short time before the opening of the morning session. If plenum fans are used they should be started in season to thoroughly warm the building by rotating the air before the opening of the morning session. The direct radiation in class-rooms should not be used while school is in session, unless the class-rooms cannot be heated without it. The heat in the sanitary vent-flues should be kept up at all times, except perhaps in very cold and windy weather. The dampers in the corridor vents should be closed at night. Care should be taken not to open the windows in the sanitary rooms and allow the wind to blow in, as the odors may under some conditions be driven out of these rooms into other parts of the building. It is much better to depend upon the sanitary vent-flues to properly ventilate these rooms by drawing the odors from the room through the sanitary closets and urinals. Liberal use of water should be made for flushing the sanitary fixtures. The janitor should be in the building in the morning in season to have the building properly heated and the ventilating apparatus in good working order before the school session opens. After cleaning and properly starting up the fires he should open the windows admitting fresh air to the cold-air rooms and properly adjust them to meet the existing conditions of wind and outside temperature. He should then close the rotating registers, open the vent dampers to the proper degree and % close the class-room doors. THE SCHOOL HOUSE. 113 When the large boilers in a steam heating system are in use the steam for heating the vent-flues should be supplied from that source ; but when the large boilers are not in use, or with a furnace system of heating, the small boiler, usually called the " summer boiler," should be used. The doors, tvindozus and transoms should be kept closed while school is in session in order to obtain the best results front the heating and ventilating system, and to secure a proper circula- tion of air in the rooms. Springs or door-checks, if provided on all outside doors, will soon repay the extra expense by the saving of coal. Janitors should be held to a strict accountability that the heating, ventilating and sanitary appliances in the buildings under their care are managed in a manner to secure the best results. While they should not be blamed for improperly designed or constructed apparatus, yet they should be required to secure the best possible results obtainable from the apparatus under their control and to keep the same in good condition. The janitor should see that the boilers or furnaces are left in proper condition at the end of the school term. If a mechanical system is used all parts of it should also be attended to. If any defects develop or accidents occur to the boilers, piping, valves or other parts of a steam-heating system, or in the furnaces or stack- heaters under his charge, the proper authorities should at once be notified in order that the required repairs may be made promptly. All accumulations of ashes or rubbish should be promptly removed from the building. No inflammable or combustible material should be placed or allowed to accumulate in any closet or near a stairway or means of exit. Where the pupils use paper instead of slates for their work, as is now generally the case in Massachusetts schools, care should be taken that it be promptly burned or removed from the building, and not allowed to accumulate in the basement or in any closet. All the rooms in the building should be thoroughly and frequently swept and dusted, the sanitary rooms and fixtures washed and disinfectants freely used if required. Where outside sanitary buildings are used they are often found to be in a very bad condition. The janitor should be required to inspect all the rooms and outbuildings under his charge at least once a day and should be held responsible for their cleanliness. He should investigate all cases of misuse of the sanitaries and report to the principal of the school or the school committee. 114 THE SCHOOL HOUSE. The playgrounds or yards should be kept in a neat condition and not become the repository of rubbish of any kind. In winter the janitor should see that all walks and entrances are properly freed from snow and ice, and that the basement doors are opened a reasonable time before commencement of the school session. The average annual amount of coal burned in well-heated and ventilated school buildings in Massachusetts is about ten tons per class-room. This includes the basement, corridors and small rooms in an ordinary schoolhouse. ' Where much in excess of this amount is used, unless in a build- ing in a very exposed location, or one badly constructed, or where the system of heating and ventilation is badly designed, it is fair to presume that the janitor has not been careful in managing the fires. Where, as is sometimes claimed, only seven or eight tons of coal are burned per year, it will be found that the air supply has been restricted to an amount below what is required for good ventilation. Some janitors, either to make less work for themselves, or to establish a record for economy in fuel, shut off the fresh-air supply, or fail to maintain proper heat in the vent-flue heaters. In cities and large towns much better janitor service would be obtained if a competent "head janitor" was employed and if it was made a part of his duty to see that the other janitors were fully instructed in and properly performed their duties. It is false economy to employ, as is often done, an incompetent or lazy janitor because he can be hired cheap. It is not advisable that one janitor should have charge of several buildings, sometimes situated at a considerable distance from each other. Very frequently janitors do not receive suitable compensation for their work. This is more often the case in small towns than in cities. Fair compensation should be given for intelligent and faith- ful service. The following extracts from a paper read at the twelfth annual convention of the International Convention of Factory Inspectors at Boston in 1898, by Thomas Hawley, State Inspector of Boilers and Examiner of Engineers and Firemen, contain many facts which it would be advisable for school committees, superintendents and principals of schools to carefully consider : " There is another class of boiler that has received considerable attention from the department ; namely, those in schoolhouses and public buildings. THE SCHOOL HOUSE. 115 While a very large number of firms and manufacturers have sadly neglected their boilers and allowed them to go without inspection, those who control the steam plants of large heating plants seem to have been more guilty in this respect Ver\ T few school boilers have been found upon which it was not necessary to order extensive changes to make them safe to be run. In some cities many of the boilers have been punctured with a blow from the light hammer each inspector uses. It has been the policy of the department to have the changes made and the boilers replaced or made safe without let- ting the facts be publicly known because of the possible alarming of parents, and very many boilers have thus been repaired without the pupils or parents knowing or suspecting that they had been near a dangerous boiler. The reason for this neglect seems difficult to understand. It may arise from the fact that in very many places the condition of the boilers is cared for by the public buildings department or committee of the city or town, and the boilers operated and under the care during the year of janitors appointed by the school committee. Each tries to put as much of the work as possible upon the other, or at least such would seem to be the case. I have found boilers in schools full of mud and deposits up to the hand holes, barrel staves, and bricks, tubes nearly filled up with soot, and back connections filled clear to the boiler with soot and ashes, hand-hole plates in the boiler rusted solid so they had to be broken off, showing the boilers had neither been opened for inspection nor cleaned for years. The janitors claim it is the work of the building department, and that department claims that if they give the school committee a good boiler and that committee provides the man to run it, that man should see it was run properly, and properly cared fbr and cleaned. Between the two, however, the boiler is not long in getting into dangerous shape ; and it has been necessary to condemn school boilers entirely in some cases only after a few years' use. I have further found this condition to continue even after the inspector's first inspection, when the boiler comes to be again inspected, and it is the rule almost rather than the exception to find schoolhouse boilers in a dirty uncared-for condition, that shortens their lives, develops many defects, and in a filthy condition unfit for a proper inspec- tion. The matter, in fact, it seems to me, has been complicated in one way, by the inspector making a third person upon whom the others rely, and they will now get only such attention as the inspector can give in his annual visit. It appears that there is claimed to be objections to having the boilers operated by persons not in the employ of the building department, it being claimed that all employees in schools should be controlled by the school committee. Of the merits of that contention I know nothing, but it does seem as though the two together could arrange that the boiler should have proper care and attention, or such an important and dangerous part of the school equipment as the boiler is should be under the responsibility of the school committee. Prior to the enactment of this law, boilers have exploded in schools in this State with disastrous results and in spite of the poor care they usually obtain, the regular inspection now made does provide a material safeguard. " In other instances, too, heating boilers are found much neglected. The claim is made that they are run at such low pressure that they cannot explode. Yet I have pieces and sections of these boilers in my possession that have exploded and very recently, and with disastrous results. Many of these sec- tional boilers are of cast iron, and are bad in design, cheap in material, and 116 the school house. improperly set up and inadequately fitted with safety appliances. They have been found with devices that bore the name of ''safety-valve," but were safety-valves in name only. This most important fitting on a boiler is very frequently found altogether inadequate in size and in unfit condition. I have within a month taken safety-valves from school boilers which were stuck so solid they could not be moved with a hammer, and had become so by neglect since the previous inspection." The following rules for janitors and firemen having charge of low-pressure steam-heating boilers are the requirements of the Hartford Steam Boiler Inspection and Insurance Company. 1. Getting Ready to Start. The attendant should see that all joints are properly packed, and that none leak on filling the boiler with water. The gauge cocks, water gauge, and safety valve should be carefully examined that all are free and in good order. All valves in piping and radiators and air valves, should be examined and seen to be in order, and that all necessary packing or repairs have been done. 2. Condition of Water. The first dutj' of an engineer when he enters his boiler-room in the morn- ing is to ascertain how many gauges of water there are in his boilers. Never unbank or replenish the fires until this is done. Accidents have occurred and many boilers ruined from neglect of this precaution. 3. Raising Steam and Management of Valves. All steam and return pipes should be closed before fires are started. When steam has been raised to working pressure, the steam valves should be opened very slowly. After the boiler pressure is established in the pipes the return valves can be opened, allowing the water of condensation to flow back to the boiler. Whenever necessary to shut off at the boiler or any section of heat- ing system, the return or drip valves should be closed first and then the steam valves. In letting on the steam the supply or steam valves should be first opened and then the return or drip valves. This caution is important. 4. Low Water. In case of low water, immediately cover the fires with ashes, or if no ashes are at hand, use fresh coal, and shut the ash pit and open the fire doors. Do not turn on the feed under any circumstances or tamper with or open the safety valves. Let the steam outlets remain as they are 5. Feeding. When necessary to take fresh water the boiler should be fed as slowly .as possible to avoid unnecessary contraction and leakage at joints. 6. Gauge Cocks and Water Gauge. Keep gauge cocks clean and in constant use. Glass guages should not be relied upon altogether. 7. Safety Valves. Raise the safety valves cautiously, and frequently, as they are liable to become fast in their seats. THE SCHOOL HOUSE. 117 8. Safety Valve, Automatic Regulator, and Steam Gauge. Should the gauge at any time indicate the limit of pressure to which the regulator is adjusted without its controlling the draft, the regulator should be examined and disconnected from the damper or draft door. If the regu- lator works quickly and well the trouble is in the damper or draft door, and it should at once be cleaned and made to work freely. Should the regulator fail to work, or work very slowly, the pipe connection to the boiler is choked and should be cleaned. See that pressure gauge, regulator, and safety valve agree; in case of difference, notify the company's inspectors. 9. Clean Plates and Heating Surfaces. Particular attention should be taken to keep plates and parts of boilers exposed to the fire perfectly clean. Also, all tubes, flues and connections well swept. This is particularly necessary in many types of small heating boilers with large heating surfaces and small heat passages, as they soon foul if neglected. Strict attention to this rule is necessary for full economy and capacity of boilers. 10. Blowing Off. If necessary to blow down during the season, the fires should be hauled and furnaces and bridge wall cleaned at least two hours before blowing down. Allow the boiler to stand until cool before filling with cold water. 11. Laying up Boilers for the Season. Haul fires, clean furnaces, and run off the water while hot. Thoroughly clean all heating surfaces at once. Remove hand and man-hole plates, dry out water if any remains, and leave the boiler thoroughly clean and dry. Drain all water from return drip-pipes. All good systems are provided with drip-cocks at lowest point in return pipes for this purpose. During the sum- mer see that no water can drip or moisture collect in or around the boiler. 12. Piping, Radiators, and Settings. Mark all joints that have shown signs of leakage and need packing; also air-cocks and valves and anything that may need repairs before using another season. If repairs are needed to boiler settings see what they are and have them made while the boiler is idle. Inspectors Will Give Special Instructions in Cases Not Covered by Tkese Rules. £3T If the Boiler shows distress or unusual behavior notify the Company at once. A Few General Suggestions for Operating Heating and Ventilating Apparatus in School Buildings. Furnaces. Care should be taken not to have too deep or heavy a fire in the furnaces during Spring and Fall, as there is great danger of over- heating the school-rooms. During cold winter weather run deep, full fires in the furnaces with coal up to within three inches of the top of the fire-pot at the edges, and well crowned above that level toward the middle. 118 THE SCHOOL HOUSE. During extreme cold weather the grate-bars should be turned over at least twice each day. Ashes should not be allowed to accumulate in the ash-pits. Fresh-Air Windows. The fresh-air windows should be wide open daytimes in mild and calm weather, and never less than one-quarter open even in extreme weather, as judicious handling of the school-room vent- duct dampers should prevent the passage of too much cold air out of the building, thereby checking the inflow through the furnace chambers. Always close the fresh-air windows tightly nights, Sundays and vacations, but never close the fresh-air windows entirely when school is in session. Controlling Temperature of School-rooms . The temperature of the air entering each school-room should be regulated by the teacher occupying the room, — this is done by pulling the warm-air chain, or the cold-air chain, as the needs of the moment may demand. The teacher should pull the necessary chain but a little way at a time, — this to prevent too sudden a rise or drop in the temperature of the air entering the school-room. Dampers in Ventilating Dttcts. The outflow of air from each school-room is controlled by a damper, which should be adjusted by the janitor before each session of school, according to the outside conditions. In mild and calm weather, this damper should be wide open ; but when the weather is cold and windy, it should be partially closed. Never should it be closed entirely when school is in session. During extremely windy weather the vent-duct, unless controlled by the use of this damper, might take out from the school-rooms a larger quantity of air than the warm-air ducts could provide suffi- ciently heated, — the excess outflow finding its way into the school- room cold, through leakage around the windows and doors and through the walls. Intelligence should be used in operating these vent-duct dampers. Schoolroom Windows and Doors. A much better circulation of air within the school-rooms can be obtained if the windows and doors of the school-rooms be kept closed. Windows and doors should always be kept closed when the large furnaces are in operation. THE SCHOOL HOUSE. 119 If, when the chains which allow the cool air to enter the school- rooms are pulled way down, the furnace drafts entirely checked, and it is still found that the school-rooms are uncomfortably warm, doors and windows may then be opened at discretion of the teacher. Air Rotation. At the close of school at night the fresh-air windows should be tightly closed and passage of air out from the building through the vent-ducts entirely checked ; the rotating dampers which allow air from the school-rooms to pass back to the furnaces should then be opened, and the furnace fires fixed for the night. A circulation of air within the building will thus be established, and a reasonable temperature maintained in the school-rooms during the night, with the minimum consumption of fuel. Stack- Heater . When the weather is cold enough to require good fires in the large furnaces which heat the school-rooms, these furnaces will often furnish enough power to move the air required ; but, on the other hand, when only low fires are needed in the large furnaces, it may be necessary to run the stack-heater in order to move the desired volume of air through the school-rooms. In warm or muggy weather, a good fire should always be kept in the stack-heater, not only for the ventilation of the school-rooms, but for the ventilation of the sanitaries as well. With Steam- Boiler Auxiliary . The steam boiler supplies steam for the radiators in the corridors and small rooms, and also furnishes heat for the vent-ducts. The steam may be supplied to the radiators in the corridors and small rooms when desired. In warm or muggy weather the vent-flue radiators should always be kept hot, in order to secure the proper ventilation of the school-rooms. Printed instructions (in large type) as above, if posted where they can be readily seen by the janitor, will be of great service to him when first taking charge of the heating and ventilating apparatus in a schoolhouse. CHAPTER IX. SANITARIES. THE sanitary appliances in schoolhouses should receive careful attention, not only when being installed, but also from the janitor. For buildings of large size the sanitary fixtures are generally placed in the basement, or, what would be better, in an extension in which they can be reached from the class-room floors and located where they can be properly ventilated, independently of the other parts of the building. On account of the cost of construction, and frequently from an architectural point, this is not often done, and part of the basement is utilized for that purpose. Where a suitable water supply is available and the fixtures are of good construction and properly placed and ventilated, the base- ment is not an objectionable place. Individual closets and fixtures are preferable to those known as range closets or latrines, but where the latter are properly flushed and vented they are not objectionable and are frequently used on account of the lower cost. With individual seat bowls those having a seat vent three or four inches diameter are to be preferred. The individual bowls should be vented into a pipe increasing in size as additional vents are connected and leading to a heated vent- flue or one where a fan is provided. In large and the best class of school buildings fans are used, but are more expensive than steam-heated flues. The partitions between the closets should be raised on metal supports from six to ten inches above the cement floor of the basement and no woodwork on or around the bowls should be used, except such as is required for the seats. This allows the janitor to use a hose freely and prevents the accumulation of offen- sive matter in places not easily reached. Each bowl should be provided with an automatic flushing device, of which there are several on the market that give good results. Apparatus is frequently used by which the whole number of bowls are automatically flushed at regular intervals. THE SCHOOL HOUSE. 121 When range closets are used they should have a large vent and flush. It is better to have a separate vent for each seat and to unite the several vents into one main vent. Range closets should not be incased in wood on the sides or ends, and the full width between the partitions should be hinged in order that the whole length of the range can be thoroughly cleaned. The waste-pipe should be of ample size but not too large to prevent thorough flushing. For the main pipe six inches is a good size. Extra heavy iron pipe within the building is to be preferred to vitrified tile pipe, on account of the liability of tile pipe to become separated at the joints and allow leakage into the ground under the basement floor. The iron pipe should extend well beyond the foundation wall and in all cases should be well trapped and provided with suitable clean-outs. The writer has seen tile pipes that had been improperly connected or not made water-tight that had leaked so badly as to saturate the ground for a considerable distance, and where it has been found necessary to take up the floor and remove a considerable quantity of earth, replace it with fresh and substitute iron pipe. Where cremating closets have been used the saturation of the earth has been more noticeable than with water-flushed fixtures. Where there was no available water supply for flushing closets cremating closets have been used, and where the vaults were con- structed of brick laid in and covered with Portland cement and a good drain provided to remove the liquid matter, and where ample ventilation into a heated flue was provided, they have not been objectionable if properly cared for by the janitor. Odors were not perceived in the building, but complaints have been made by per- sons residing near the buildings when the closets were burned out. Where a water supply can be had it is better to use flushing closets. Where a water supply is available, but no system of sewers, flushing closets or range closets can be used by constructing a double cesspool; that is, two cesspools located at such a distance from the building that there is no danger of the leakage finding a way under the building — one cesspool to receive the waste-pipe from the sanitary fixtures and to allow the heavier and more solid matter to settle, the other to be constructed of brick or field stone to allow the liquid to filter off. The two cesspools are connected by a siphon pipe (six inches in diameter), which will, when the first receptacle has become partly 122 THE SCHOOL HOUSE. filled with liquid, transfer it to the second or filtering cesspool. This arrangement cannot well be vised where the ground is con- stantly wet or where water in the ground is much above the bottom of the cesspool, or in clay. Each cesspool should be provided with a perforated manhole cover to prevent an accumulated gas from forcing its way through the trap and entering the schoolhouse basement. The urinals in a schoolhouse basement, where individual fixtures are not used, should be of slate, and should have suitable divisions for the older grades of pupils. In many school buildings the divisions are omitted on account of the additional cost of construction. A urinal has been constructed for an eight-room school building in accordance with the following specifications, and used with satisfactory results : "A gutter slab, 8 feet long and 18 inches wide and 3£ inches thick, in one piece ; one floor slab 8 feet long, 2 feet 6 inches wide and 1^ inches thick, sloped to the gutter slab; two end slabs 5 feet high, 2 feet 6 inches wide and 1 inch thick, and two back slabs each 4 feet long, 5 feet high and 1 inch thick, making the urinal when completed 8 feet long, 5 feet high and 3 feet 3f inches wide, including the floor slab. The gutter is to be countersunk 2^- inches deep at the outlet and 1 inch deep at the summit ; the back slants 5 inches and is to be grooved f-inch into ends, and all are to be grooved ^-inch into the gutter slab ; all to be strongly clamped together and bolted to the brickwork, using brass clamps and brass expansion-bolts. The floor slab laps 3£ inches on the gutter and is closely fitted to the ends ; the outer or -waste-pipe is a brass cesspool, having 3-inch waste trapped. "A J-inch brass flush-pipe runs the entire length, placed within two inches of the top, and perforated so as to give a uniform and even flush; this will have a controlling valve. " The end slab near the outlet has an 8 by 10 inches opening to receive an 8 by 10 uptake vent-pipe and an 8 by 8-inch ventilating- hood which runs on top of the back slab the entire length. This connects with an 8 by 8-inch uptake vent-pipe, both of these uptake pipes and hood being made of heavy galvanized iron, properly secured in place. The uptake pipes are connected near the ceiling with the vent-duct leading to the heated brick vent-flue. All exposed parts of the slate are to be planed, rubbed smooth and well-oiled, the joints filled with slate cement in the best manner." A better arrangement is that of a slate urinal vented at the bottom of the front slab (having at least 12 square inches of THE SCHOOL HOUSE. 123 opening for each 16 inches length) into a space between the front inclined slab and a perpendicular back slab, the space at the top to be at least four inches wide and the full length of the slabs and covered on the ends and top by slate slabs, except where it is vented near the center of the top by a galvanized-iron vent-pipe four inches wide and at least 20 inches long, which changes its form into a 10 inches diameter round pipe connected with a heated brick flue. The perpendicular back slab is grooved i-inch into the gutter slab. The inclined front slab at the bottom projects over the gutter at least three inches. The Boston Board of Schoolhouse Commissioners recommend, for water-closets and urinals, " Ventilation through fixtures, back of urinals, and 13 square inches local vent in water-closets. "Water-closets. The basement water-closets for primary and certain grammar schools are, approved washout vitreous earthen- ware or enamel iron latrines, or short hopper closets ; elsewhere a heavy wash-down closet, all as specified by the Commissioners, 13 square inches local vent from each section of closet, automatic flush. "Slate partitions for latrines resting on top of range, 5 feet 6 inches high and about 4 feet wide ; for closets 8 inches above floor, 5 feet 6 inches by 6 feet high and 4 feet wide; in both cases supported at ends with iron pipe from floor to ceiling. No doors. (These may be added later.) " Urinals. The urinals will be of slate, floor slab and trough, the back 4 feet 6 inches high, without partitions, flushed auto- matically with |-inch perforated pipe, vented at bottom (opening 10 square inches for each 16 inches length) into space behind back. " Piping. Cast-iron must be in trenches in basement, running trap with direct indirect fresh-air inlets, clean-outs at every change of direction ; soils and vents exposed as far as possible, no asphaltum, but oil-tested red lead and three coats paint. "Supplies exposed as far as possible ; where covered may be lead, elsewhere brass, no nickel plated. Hot- water for janitor's use in basement, and, if convenient, for master's and teachers' toilets. Supply from boiler, and from summer boiler, if any, or from a gas-heater." All plumbing should be carefully tested to ascertain if it is tight and well trapped, especially where smaller pipes enter the main drain. ' 124 THE SCHOOL HOUSE. Where water-closets are provided in teachers' toilet rooms they should be well vented. Soapstone sinks are frequently used in the basement in place of the ordinary cast-iron ones. Enameled iron is sometimes used. Many school buildings have stream drinking founts instead of faucets and dippers. Outside Saizitary Building's. The care of sanitary buildings in many towns and villages is a matter that is often neglected, and frequently they are found in a condition that does not bring credit to those who have the imme- diate care of such buildings. This is something to which school boards and teachers should give more attention than they usually do. They should see that such places are kept in at least a decent condition and that the vaults are properly cleaned. The janitor should be required to visit the sanitary building daily, cover the contents of the vault with fresh earth or ashes, and see that the seats, urinals and floors are in good condition. In winter especially these buildings are often found in bad condi- tion, as there is seldom any provision for heating. While- a stove in such buildings would add much to the comfort of the pupils, practically it would be of little use, as the fire would not be properly tended by the ordinary janitor, and some committees would object to.what they would call a needless waste of fuel. Where outside privies are used they should be placed at such a distance from the schoolhouse that odors will not reach the class- rooms when the wind is blowing from the direction of the sanitary building. When practicable they should not be located in a direc- tion from which the prevailing winds blow. Particular care should be taken that they are not located near the fresh-air supply for the furnaces or indirect radiators in the school building. When such buildings are used it is advisable to provide a tight vault with the walls laid in cement and covered on the inside and bottom with cement. A vault three or four feet deep and from four to five feet wide, extending the length of the building, will be found of ample size if cleaned out as often as it should be. The walls should be not less than 12 inches thick (some are 16), and the bottom of cement not less than two inches thick if the ground is solid, but if the building is placed where the ground is THE SCHOOL HOUSE. 125 wet or not firm, there should be below the cement a layer of con- crete not less than four inches thick. The vault should extend beyond the rear of the building and be covered with inclined and hinged doors for removing the contents. On the rear of the building, and extending not less than two feet above the ridge, should be a ventilating shaft leading from the vault. The windows should be hinged and fitted with attachments for readily opening and closing. Locks should be placed on the doors for closing the building when the schoolhouse is not occupied. Where the ordinary trough urinal is used it should be well covered with sheet zinc and the floor under and at least three feet in front should be covered with sheet zinc and the joints made water-tight. Hinged self-closing covers should be furnished for the seats. Where it is not practicable to provide separate buildings for boys and girls, one with a partition may be used, and a board division fence or divided covered way leading from the schoolhouse to the building. Where the sanitary building is attached to the schoolhouse by a covered way (which is not always advisable), self-closing doors should be provided at each end and ample provision made for doors or louvres in the sides to prevent odors entering the school house. Brick piers are sometimes placed in the vault under the rear wall of the building if it is of considerable length. Three-inch iron pipe is preferable to the brick piers, as the vaults can be more readily cleaned when this is used. Whatever class of sanitary fixtures or buMdings are provided for schoolhouses it is requisite that constant supervision should be exercised by teachers and janitors to have them kept in good con- dition. It should be a teacher's duty to see that the janitor faith- fully attends to that part of his work. In many sanitary buildings, especially in the smaller towns, the writer has found conditions that should not be tolerated and would not have been allowed to exist if either the school committee or teachers had taken means to ascertain whether the janitor was attending to this part of his duty. Vaults were found that apparently had not been cleaned out for years, seats and floors covered with filth, obscene writing on the walls, and doors with hinges and fastenings broken. 126 THE SCHOOL HOUSE. It has frequently been necessary to order seats and floors removed and new ones substituted in outside buildings, and in some cases new buildings were built. Such unsanitary conditions are demoralizing, and if parents had known of the existing conditions there would have been strong- protests entered with the school committee. Where a supply of fresh earth has not been obtained, kept dry and free from freezing, in cold weather sifted ashes from the furnaces or boilers can be used to good advantage in the vaults. In some badly-constructed cremating closets and in some of the so-called " foul air gathering rooms" with poorly cemented floors, trouble has been caused by the breaking, scaling or cracking of the cement, which allowed the liquid matter to soak into the ground under the basement floor and extensive repairs and alterations were required. Where any class of cremating closets are used in school- houses, extra care should be taken that the vaults are made per- fectly water-tight, thoroughly built and well drained. The heat in sanitary vent-shafts or ducts should be maintained at all times during the school term, except, perhaps, when there is a very considerable difference between the temperature in and out- side the building, or when a very strong wind is blowing across the top of the shaft and causing an outward flow of air. The sanitary vent-flue should never be placed in a position in which back drafts may be caused by the wind being deflected by roofs, towers or other projections. When a contagious disease appears among the pupils the entire schoolhouse should at once be thoroughly fumigated and disinfected under the direction of a competent person. PART II Plans and Descriptions OF School Houses uuhhjui^— =dnir MB 1 iDD D D D 1 iDD D D D 1 iDQ D D Q. I i D D D D ODD ;DDD b d n •^ N,, (E DDDDDhDpp DDDDDIDDD q- 'V- - -- o PLANS AND DESCRIPTIONS OF SCHOOL HOUSES. PLAX of a one-story, one-room schoolhouse with sections of heating and ventilating apparatus. The school-room is 28 by 32 feet and 12 feet high, with seats for 48 pupils. In front are two clothing rooms, one for boys and one for girls. A cast-iron sink is provided in each. There is a closet opening from the school-room for the teacher. Between the clothing-rooms are the furnace-room and fuel-bin. The heating is bv a medium-sized portable furnace. Fresh air is taken in through a galvanized-iron duct under the floor. This duct is 48 by 16 inches where it passes through the underpinning, and the bottom is slightly inclined toward the outside to allow rain that may be driven in to run out. The inlet is protected by a wire grill of one-eigbth-inch wire set in a channel-iron frame. A valve, with a pulley and a chain passing up into the furnace room, is provided, with a suitable catch to hold the valve in any desired position when a strong wind is blowing, or when the damper is closed at night. Before reaching the furnace the duct is tapped by a perpendicular one 24 by 30 inches, to furnish cold air for mixing with the warm air from the furnace when it is desired to reduce the temperature and yet supply fresh air to the school-room. A mixing-valve with pulleys and chain leading to the school- room is provided to enable the teacher to regulate the temperature. A suitable catch (as shown in another plate) is provided to hold the -chain and damper in any desired position. Warm air enters the school-room through an opening 30 by 30 inches, covered with a wire grill of one-eighth inch wire, one-and- one-half-inch diamond mesh, set in a channel-iron frame. The bottom of this opening is eight feet above the floor. The warm air is thrown forward across the ceiling, spreading till it reaches the three outer or cold sides, where it is cooled and falls, and is drawn back across the lower part of the room and removed by the exhaust vent stack. Note. — The method of setting up this heating apparatus was designed by the writer and has given satisfactory results where used. 130 THE SCHOOL HOUSE. In the top of the cold-air duct, before it reaches the upright part, is a trap-door covered on the bottom with galvanized iron which opens up into the furnace room. This is for rotating the air within the building at night or when the school-room is not occupied. By closing the outer damper in the fresh-air duct, closing the vent shaft opening from the school-room, and opening the doors between the school-room and furnace-room, the air is rotated through the furnace and a considerable saving of fuel is made. This trap-door should never be opened when the school-room is occupied. The exhaust vent or foul-air shaft has four-inch brick walls, and is 30 by 24 inches inside. Adjoining, and in the same stack, are the smoke flues for the furnace and vent-shaft heater. A small stove or " stack-heater," supported on two iron bars, is placed in the vent shaft just above the foul-air entrance. The foul-air vent opening is 24 by 30 inches, and the bottom is at the level of the floor, being covered with a wire grill similar to that at the warm-air inlet. A curved galvanized-iron damper is placed in the opening to regulate the outflow of air as may be desired on account of outside temperature or wind, or to close at night or when the school-room is not in use. , Plates Nos. II and III show plan and sections of what is known as the portable schoolhouse — a one-room school building for temporary use where the larger buildings are overcrowded, or for use until better accommodation can be provided. The building is constructed of light timbers and covered with matched and battened boards. The roof boards are covered with canvas, painted three coats. The building is supported on cedar posts and the space between the floor and the ground is inclosed with two thicknesses of matched boards, the outside boarding being perpendicular and the inside placed horizontally. 'The inside of the building is sheathed on the sides, ends and ceiling with matched boards. Between the upper and lower floor boards are two thicknesses of heavy building paper. The heating is by a jacketed stove or small portable furnace, which receives the air to be heated and for ventilation through a galvanized-iron duct leading from under the front platform, which is not boarded on the end, but provided with open lattice-work. A damper is provided in this fresh-air duct by which the quantity of air to be heated is regulated according to the temperature of the Note. — The method of setting up this heating apparatus was designed by the writer and has given good results. THE SCHOOL HOUSE. 131 o-*2 - - - -9,9 - - 132 THE SCHOOL HOUSE. THE SCHOOL HOUSE. 133 I outside air or the force of the wind. This damper is operated bv a pulley and a chain passing up into the school-room. The air passes up between the casing and the stove and is intro- duced into the school-room through a curved top, which changes the direction of the current and throws the air across the ceiling to the coldest part of the room. This curved top is movable, and can be changed to throw the air against the direction of the prevail- ing wind when desirable, thereby securing a more even distribution of heat in the schoolroom. In the floor of the schoolroom and behind the jacketed stove is a trap-door opening into the fresh-air duct. By closing the outer damper in the fresh-air duct, opening the trap-door and closing the damper at the opening into the ventilating shaft, the air can be rotated through the building at night. This also enables the janitor to quickly warm the room in the morning before the school session begins. The trap-door should never be opened while the school is in session. The ventilation is by means of a galvanized-iron shaft in which is placed a small stove or " stack-heater" just above the top of the vent opening, the bottom of which opening is at the floor level. The stack-heater is supported on two iron bars and the lower part of the ventilating shaft from the floor to above the heater is provided with a double casing, filled with an non-heat-conducting material, preferably asbestos. This vent opening is covered by a detachable wire grill. At the vent opening is placed a curved galvanized-iron damper, operated by a chain and catch. The smoke from the jacketed stove and from the stack-heater enters a galvanized-iron smoke-pipe which passes up near the center of the vent-shaft and above a galvanized-iron hood or cap above the top of the shaft. The outer clothing of the pupils is to be hung on hooks in the porch clothing room, which is ventilated into the vent-shaft through a 10 by 12 inch register at the floor level, having valves. The vent-shaft is 24 bv 30 inches, inside measurement. The opening from the school-room is 30 inches long by 24 inches high. The galvanized-iron fresh-air duct is 36 by 16 inches, and the circular opening in the movable top above the jacketed stove is 24 inches diameter. A small closet is provided for the teacher. Plates IV, V and VI. Basement, floor plan and plan and sections of heating and ventilating apparatus for a one-story two-room wooden 134 THE SCHOOL HOUSE. □ □ □ THE SCHOOL HOUSE. 135 136 THE SCHOOL HOUSE. PLATE VI. SECTION THROUGH VENT SHAFT THE SCHOOL HOUSE. 137 schoolhouse, intended to accommodate forty-eight pupils in each room. The rooms are 28 by 32 by 12 feet, lighted on two sides from the left and rear of the pupils. The teachers' platforms are omitted and a table-desk provided in each room. The pupils' outer garments are hung on racks in the corridor, in which is a well-trapped sink and a looking-glass. The basement is 9 feet 9 inches high, well lighted, the bottom concreted and covered with half an inch of Portland cement, and contains separate rooms for boys and girls, sanitary closets, coal- bins, cold-air room, furnaces and vent-shaft heaters. A well- trapped sink is also provided. If double run of sash or outside windows are provided for the class-rooms, especially if the building is in an exposed location, a considerable saving can be made in the amount of coal required. The school-rooms are heated by a large-size furnace encased in a double casing of galvanized iron set up inside a cold-air room, which is built of brick. If desired, an additional covering of non- heat-conducting material can be added to the outer casing of the furnace The fresh air is admitted to the cold-air room through two windows hinged and protected on the outside by a stout wire grating, and provided with cords and pulleys for regulating the amount of air admitted. A pit extends around and under the furnace, causing the air to be more evenly distributed than by the usual method of set- ting. The space between the two casings prevents the air being too rapidly cooled from the outside while and after passing the fire-pot. Over the top of the furnace are the mixing-valves for regulating the temperature of the air for the school-rooms. The cold air for mixing passes over the top casing of the furnace direct to the mixing-valves, each of which is operated from the school-room by pulleys, chain and catch. The warm-air ducts are 24 by 30 inches in cross-section. The warm air is admitted into each class-room through an opening 30 by 30 inches, covered by a wire grill set in a channel-iron frame. The warm-air inlets are placed on the inner or warm side of the room, but near the outer or rear wall of the building, and Note. — The method of setting this furnace was designed by the writer and has given very satisfactory results where used. 138 THE SCHOOL HOUSE. the bottom of the grill is eight feet above the floor. The temperature is regulated by the mixing-valves over the furnace. A four-inch diameter metallic thermometer with perforated back and sides, placed on the wire grill about two-thirds up from the bottom, half-way between the sides, will be of much service to the teacher in regulating the temperature. Two or three pieces of ribbon about one-quarter inch wide and about one foot long, tied into the grill just below the thermometer, will enable the teacher to judge of the amount and velocity of the incoming air. A thermometer, placed at about the level of the pupils' heads, when seated, and located on the partition in rear of the teacher's desk, should be provided ; also one for outside use, placed where the sun will not shine directly on it, for the janitor's use. The small supplementary heater for the corridor or hallway is intended for use in very cold or wet weather, also for drying the pupils' clothing and for a foot-warmer and drier. It also provides for moderately warming the basement. Each warm-air pipe from this heater is provided with a damper. This heater receives its air supply through a galvanized-iron duct and hinged window covered on the outside with stout wire-netting, and draws the air from under the front platform. In the stair risers in front and on each end of the outside front platform are wire-covered openings to admit fresh air to supply the heater. A register face, 27 by 38 inches, with a hinged door underneath, is provided in the floor of the closet between the two class-rooms, and opens into the cold-air room below for the purpose of rotating the air through the building at night or when the schools are not in session. The foul air from each school-room is taken from the floor level at the inner or warm corner of the room through a register face (without valves) 27 by 38 inches and a galvanized-iron duct down to the bottom of the foul-air shaft or stack, which it enters through an opening 24 inches high by 30 inches long. A valve or damper operated by a chain from the school-room is provided in each galvanized-iron foul-air duct. The brick foul-air shaft is 36 by 48 inches inside, and has a brick partition extending across the narrowest way to act as a cut-off and to prevent cross drafts from the ducts. This partition extends above the top of the foul-air entrances and on top of it is placed a cast-iron stove or "stack heater" with its smoke-pipe connected with a separate smoke flue. The fuel door and draft for the stack heater are tended from outside the shaft. THE SCHOOL HOUSE. 139 A damper is provided in the smoke-pipe and operated by a rod extending through to the front of the shaft. A manhole door is provided under the stack heater and in the front of the shaft. The foul air from the corridor or hallway is taken out through a wire grill, 12 by 12 inches, under the sink and directly into the vent shaft ; a galvanized-iron deflector, hinged at the bottom and arranged to open or close by a chain and catch is placed at this opening. This vent opening is desirable for removing the foul air and odors from the clothing and preventing them from entering the school-room. The sanitary closets in the basement are of the individual, short hopper, automatic flushing pattern, having a four-inch diameter seat vent connecting with a duct (increasing in size as each closet is added) to the sanitary vent-flue, which is 16 by 48 inches, inside dimensions. The boys' urinal is of oiled slate, with perforated flushing pipe at the top and vented into the same vent-flue as the closets. An underground drain-pipe is provided for the closets and urinal, and connects with a sewer or a double leaching cesspool well in the rear of the building. No separate vent opening is provided for the basement, as it will be well ventilated through the sanitary fixtures and vent-shaft if the stack-heater which is placed in the sanitary vent-shaft is properly located and a fire maintained therein. Hose for washing out should be provided and the underground drain thoroughly trapped. If there is no available water supply for the sanitary fixtures they should be placed outside in a separate building and at a good distance from the school. A matched board removable porch on the front platform is an advantage in winter and will save fuel. Plates VII, VIII and IX show plans of basement, first and second stories, and a section through vent-shaft for a two-story two-room schoolhouse. This building belongs to a class of which many were built in Massachusetts some years ago and were practically without ventila- tion, except by means of windows and doors. They were often heated by wood-burning stoves. The heating and ventilation of such schoolhouses may be made satisfactory if constructed as shown herein. In the basement is located a large brick-set furnace with a brick cold-air room, connected with the outside air by a galvanized-iron 140 THE SCHOOL HOUSE. THE SCHOOL HOUSE. 141 142 THE SCHOOL HOUSE. THE SCHOOL HOUSE. 143 duct six feet wide by two feet deep. The duct enters at the top of the cold-air room and is provided with a damper and the outer opening is protected by a stout wire grill. Two galvanized-iron ducts, 24 by 36 inches, supply warm fresh air, one to each class-room. These ducts are provided with mixing-valves or dampers to regulate the temperature of the air for the school-rooms. The setting of the furnaee and arrangement of the warm-air ducts are as shown in plates VII, VIII and IX. In the floor of the first story is a cast-iron register without valves, but provided with a hinged door opening down into the cold-air room for rotating air within the building when the schools are not in session. The ventilation of the building is by a brick stack, inside of which are the smoke flues. The foul air from the lower school- room is taken down through a cast-iron register face, 27 by 38 inches, in the floor and a galvanized-iron duct, which is gradually reduced in size to where it enters the bottom of the vent shaft, at which point it is 24 by 30 inches area. The register in the floor has no valves, but a damper operated by a chain and catch is provided. In the vent shaft, placed on iron bars just above the foul-air entrance, is a stove or "stack-heater" to raise the temperature of the outgoing air and produce a good outflow up through the vent shaft. The stack-heater should always receive its air for draft for the fire from outside the shaft. If the air for the combustion of the fuel in the stack-heater is taken from inside the stack, difficulty will be experienced in keeping the fire burning properly. The air rushing up on the outside of the heater will in a great measure destroy the draft for the fire. The foul air from the second story is taken directly into the vent shaft through an opening 30 inches long by 24 inches high, the bottom of which is at the floor level. A galvanized-iron curved damper is provided at this opening, and the opening is covered by a stout wire grill. The air brought down from the lower room and heated by the stack-heater passes up on the back of the curved damper and causes a good outflow of air from the second-story room. In each cloth- ing room is a 10 by 12-inch opening with a valved register and connecting with the vent shaft. Should it be desired to provide foot-warmers and heat the clothing rooms, it is advisable to use a small furnace (set up about 144 THE SCHOOL HOUSE. where the small coal-bin is located), which has pipes to the floor of each clothing-room. The supply of air for the small furnace should be taken from outside the building, preferably from under the front platform, which should have openings to freely admit air. A rotating register can also be used with the small furnace. When an attempt is made to heat the school-rooms and the clothing-rooms from the same furnace it is hardly ever suc- cessful. When the fresh-air supply for the large furnace is shut or partly shut off there will be a reversal of the air currents in the pipes to the lower clothing-rooms, and air will be taken down over the top of the furnace and be carried up into the school-rooms. Two standard size school-rooms are all that should be heated by a furnace, even if it is a large one. PLATE X. UU ' UI 4-i BA5CAENT FOUC liOQA 5CHOOL SMOWinO HUNTING ••• VENTILATION Plates X, XI, XII, XIII and XIV. — Plans and sections of the heating and ventilating apparatus for a two-story, four-room school- house, to be built of red brick with granite trimmings, slate roof, and copper gutters. In the basement, which is 10 feet 6 inches high and well lighted, are located the heating apparatus, fuel-room, cold-air room, sanitary fixtures and rooms for boys and girls, also bicycle racks. THE SCHOOL HOUSE. 145 PLATE XI. CLAbS PQOA riDST 5TOCY FOUB COCA 5CM00L . y — 1 "~ fli 1 Ml ■ — i '■ 1 £ I 1 f — 4 IbsT >■ — H X ^TiLATiOr- 1 L PLATE XII. - 1 I -I 1 U 5ttOW!NC MtATINC'-VCNTUAnOM MCOND 5TOCY FOUB COOA SCHOOL 146 THE SCHOOL HOUSE. THE SCHOOL HOUSE. 147 Bicycle runs are provided at each outside basement entrance. A well-trapped sink is placed in each basement room. The basement floor is of concrete and covered with Portland cement. On the first floor are two class-rooms 28 by 32 by 12 feet, intended to accommodate 49 pupils each, well lighted and the seats to be so arranged that the light will come from the left and rear of the pupils. There is also a small room for use of the teachers. Suitable closets are provided in each class-room and in the teachers' room. In the second story are two class-rooms similar to those in the first story, also a small room that can be used as a library or store- room, or as a superintendent's room. The corridors are 15 feet wide and well lighted ; clothing is hung on racks on the school-room side. The heating for the class-rooms is done by two large-size brick- set furnaces. The corridors and two small rooms are heated by a small sectional cast-iron boiler, which is also intended to furnish heat for the ventilating flues. Foot-warmers heated by the boiler are placed in the floor of the lower corridor, for use in cold or wet weather. A disc fan, operated by an electric motor, is provided for furnishing an abundant supply of fresh air in mild or moderately warm weather. In cold or windy weather the furnaces are to be used by the gravity system. If electricity is not available for running the fan it can be omitted, also the partition wall in which the fan is located. In such case the furnaces can be placed three feet nearer the rear wall. In cold weather, when it is desirable to quickly warm the class- rooms before the school session begins, the outside windows in the cold-air room and the dampers in the school-room and in the corridor vents being closed, the rotating register in the floor of the closet between the two lower class-rooms and all tbe doors in the class-rooms opened, the motor is started and the air is rotated through the building. If no fan is installed, the same arrangement of cold-air windows, dampers, rotating register and doors should be made and the air rotated by gravity. Before the school session commences or the pupils are admitted to the building, the vent-dampers should be opened, the rotating register and doors closed and the cold-air windows opened. Under 148 THE SCHOOL HOUSE. no conditions should the rotation of air through the building be allowed while the schools are in session. When using the fan during school hours, two windows and the doors in the partition in the cold-air room should be closed, the air taken in through the middle window opposite the fan and driven through the fan-opening. When using the gravity system all three windows and the two doors in the partition should be opened. The fresh warm-air flues for the class-rooms are of brick, 24 by 36 inches (area six square feet), and have mixing-valves or dampers, operated by chain, catch and pulley, by means of which the temperature of the incoming air can be properly regulated by the teachers without materially decreasing the volume. The vent-flues for the class-rooms are of brick, 24 by 30 inches (area five square feet) . The vent-flues, with the exception of the sanitary vents, have curved galvanized-iron dampers, operated by chain and catch. The sanitary vents should not be closed at any time. In each vent-flue, except the corridor vent, there are placed four sections, of five square feet each, of cast-iron radiators. These are placed just above the top of the inlet vent, spaced and inclined up and across the flue. In the corridor vent there are but two sections, or ten square feet of radiation. These radiators are connected with the small boiler and separately valved on each supply and return pipe. At night, or when the building is not occupied, the steam is shut off from the vent-flue radiators and the vent dampers closed. In extremely cold or windy weather it will not be necessary to keep steam on the vent-flue heaters, and in some cases of this kind the dampers can be partly closed, but in mild, calm or warm "weather steam should be kept on these heaters. The use of unsightly, costly and often worse than useless deflectors, diffusers and flap-valves is rendered unnecessary by properly locating the supply and vent-flues and having them of ample size and properly valved. The success of any system of heating and ventilation depends considerably on the good judgment of the janitor in operating the apparatus, and he should be carefully instructed in his duties. The teachers should also be instructed in the manner of operating the mixing- valves or dampers in the warm-air flues and the dampers in the vent-flues. Plates XV, XVI and XVII. — Plans for a two-story five-room school building- and for the heating and ventilation of the same. THE SCHOOL HOUSE. 14!) The building is to be constructed of red brick with granite trimmings, slated roof and copper gutters. There are four class-rooms and one large assembly-room or hall, which can, if desired, be divided into two class-rooms; also two PLATE XV. •Five Cocn SCHOOL . BASEMENT' '"i^t 111 " -showing-heating- and-ventilation- 5CALf OF FEET small rooms in the second story for the use of the teachers. In the basement, which has a concrete floor with a covering of Portland cement, are two sanitary rooms, cold-air rooms, boiler rooms and fuel rooms. The class-rooms are of standard size, 28 by 32 by 12 feet, intended to accommodate 49 pupils each. Transoms are over each door, except in the basement. The doors from the class and assembly-rooms open into the corridors, and each has a large 150 THE SCHOOL HOUSE. glass panel in the center to enable the teachers to see into the corridors. The corridors are 15 feet wide, with special racks on the walls for clothiner. PLATE XVI. SCAltOf PEET • FIVE COO/A SC HCBL- First story- showing-heating-and-ventflation The warm fresh air is admitted into the class-rooms through openings covered by wire grills 36 by 30 inches. The bottom of these openings is eight feet above the floor. In the assembly room the grills are 54 by 30 inches. The warm-air flues to the class- rooms are 36 by 24 inches (six square feet), and in the assembly room are 54 by 24 inches each. Each warm-air flue is provided with a galvanized-iron damper or mixing-valve to regulate the THE SCHOOL HOUSE. 151 temperature of the incoming air without materially decreasing the supply. The foul air is taken out at the floor level through wire grills, 30 by 24 inches (five square feet) . In the assembly room the outlet grill is 72 by 24 inches (12 square feet). PLATE XVII. •FIVE COQM5CHQDL- • SECOND STOPY- •5HOWING-HEATING-AND-VENTILATIOM- Each foul-air outlet vent, except the sanitary vents, is provided with a galvanized-iron damper to regulate the outflow or shut it off when the building is not occupied. In each class-room vent-flue are placed four sections of cast- iron smooth-surface radiators, each having five square feet of radiating surface (a total of 20 square feet). In the assembly- 152 THE SCHOOL HOUSE. room vent-flue are placed nine sections (45 square feet) of the same kind of radiators. These radiators are placed about one foot above the top of the vent opening from the room, evenly spaced, and inclined upward and across the flue. A vent -flue, 24 by 24 inches inside measurement, is provided for the corridors, both corridors venting into the same flue, and 15 square feet of radiation is placed above the lower corridor vent opening. The sanitary vent-flues are each 20 by 24 inches and contain 15 square feet of radiation. * The heating is by a horizontal tubular boiler, 54 inches in diameter, 15 feet 3 inches long, containing 60 three-inch tubes, 14 feet long, and rated at 48 horse-power. A small sectional boiler is also provided for heating the vent- flues when the large boiler is not in use. The piping for the vent-flues is so connected that either the large or small boiler can be used as desired. Each vent-flue heater is separately valved, both on the supply and return pipes. The radiation for each class-room consists of 400 square feet of cast-iron indirect pin radiators, of 20 square feet per section, made into three stacks of 120, 140 and 140 square feet — one section, two sections or three sections to be used as may be required. Each section is to be separately piped and valved. The assembly-hall has two distinct groups of indirect radiation, 480 square feet each, and each group is made up of four stacks, separately piped and valved. Around the outside walls are two lines of one-and-one-fourth-inch steam-pipe for use when the assembly-hall is not occupied. Two foot-warmers, each of 120 square feet, of the same kind of radiation used for the class-rooms, are provided in the lower corridor. Two lines of one-and-one-fourth-inch steam-pipe are also pro- vided in the corridors and placed under the clothing racks for drying the clothing in stormy weather. The sanitary rooms are heated by four lines of one-and-one- fourth-inch pipe, placed near the ceiling. Direct radiators are placed in the teachers' rooms and toilets. In the floor of a closet in each class-room is placed a register connecting with the cold-air room below. A tight-fitting shutter of galvanized iron is placed below the register to shut off the cold air from below when the register is not open. These registers, called rotating registers, are for rotating the air through the build- THE SCHOOL HOUSE. 153 ing when the schools are not in session. This is done as pre- viously stated in the description of a two-story four-room school building. The ventilation of the sanitary rooms and basement is through the fixtures, each closet having a four-inch diameter seat vent PLATE XVIII. ' 'UU?11I 5 ix Rocv\ school- "BASE/\ENT •SHOWING HEATING ^A / ENTILATlON• connected with a galvanized-iron duct leading from each line of closets and from the urinal to a steam-heated vent-flue. The air from the sanitary rooms being taken out through the closets and urinal vents prevents odors passing out from these rooms up into the building, as is sometimes the case when the room is vented by an outlet separate from that provided for the sanitary fixtures, or where air is forced into the sanitary room by a fan or gravity supply from the heating system. 154 THE SCHOOL HOUSE. A plenum condition should never be allowed in such rooms. An exhaust should be used instead of a plenum. Sufficient air will be supplied to keep the sanitary rooms free from odors, if taken into the sanitary rooms through a wire grill placed in the bottom of the doors leading from the basement corridor, and if the sanitary-vent flues are properly heated. PLATE XIX. l ijnf.niu ^1X BOCV\ SCHOOL ■ SCAtcormT F\R.ST 5TORY •SHOWING HF.ATINGS. VENTILATION- Plates XVIII, XIX and XX. — Plans for a six-room school building and for its heating and ventilation. The building is to be constructed of red brick with terra-cotta trimmings, slated roof and copper gutters. There are six class-rooms, each 28 by 32 by 12 feet and intended to accommodate 49 pupils. In the second story are two small rooms for the teachers' use. THE SCHOOL HOUSE. 155 The seats in four class-rooms are to be arranged to receive the light from the left and rear, and in two class-rooms the light is chiefly from the left. The corridors are 15 feet wide and contain the clothing- racks. Doors from the corridors to the class-rooms have each a large center panel of heavy glass, and transoms are provided over the doors. In the hasement are three rooms, a divided corridor, fuel and cold-air rooms. PLATE XX. 51 v roo/v school- ■Second Stody- .Showing Hfatinc & Vlntilation'- The fresh warm-air flues and the vent-flues for the class-rooms are of the same size and fitted with mixing-valves, dampers and steam radiation, as previouslv described for a four or five-room school-house, except that the sanitary vent-flues are 24 by 24 inches area. Rotating" registers are also provided. There are two foot-warmers in the lower corridor. 156 THE SCHOOL HOUSE. The general plan of the building is the same as that given for a five-room school, except that the assembly hall in the five-room building is replaced by two class-rooms, and the heating is by a combination of furnaces and steam heat. The six class-rooms are heated by three large brick-set furnaces, two rooms for each furnace. A cast-iron sectional boiler is provided for heating the corridors, vent-flues, foot-warmers and teachers' rooms. If desired, the boiler may be of sufficient size to warm the basement rooms by lines of one-and-one-fourth-inch steam-pipes placed near the ceiling. By the use of this boiler very satisfactory results are obtained, and the number of fires reduced from what •would be required if coal-burning stack-heaters and an additional furnace were used to heat the corridor and vent-flues. Plates XXI, XXII, XXIII, and XXIV. — Plans for a grammar school building. The building is to be constructed of light mottled brick with granite trimmings and slated roof, containing six class-rooms, one recitation-room, a manual -training room, two teachers' rooms, two sanitary rooms, boiler-room, coal-room and three cold-air rooms, besides the corridors and stairways. There are four class-rooms each 28 by 32 by 12 feet, two class-rooms 29 by 32 by 12 feet, each accommodating forty-nine pupils. The basement is twelve feet high, except the boiler-room and coal-room, which are two feet deeper, or fourteen feet in the clear. The basement entrances are built with a bicycle run to take bicycles down to the places provided for them. The corridors are fifteen feet wide, with walls of smooth water- struck brick -without "wood finish, being painted with light-colored gloss paint. Clothing is to be hung on special racks fastened to the walls, and there are two lines of 1^-inch steam-pipes below the racks and near the floor for drying and warming clothing in bad weather. Two foot-warmers are provided in the lower corridor. The heating is done by a two-pipe gravity return steam system. The two teachers' rooms are heated by direct radiators, the manual-training room in the basement by four lines of 1^-inch steam-pipe near the ceiling and also by indirect radiators. The boys' and girls' sanitary rooms are to be heated by four lines of 1^-inch steam-pipe near the ceiling, and ventilated through the sanitary fixtures, the seats having 4-inch diameter vents connecting with steam-heated vent-flues, with which the boys' urinal is also connected. Air is drawn into these rooms through wire grills in THE SCHOOL HOUSE. 15' 158 THE SCHOOL HOUSE. THE SCHOOL HOUSE. 159 @ rn txi 3— E^ o 1 5 J | { ST ill J a n o < u 1 ' 1 ^ h 160 THE SCHOOL HOUSE. THE SCHOOL HOUSE. 161 the bottom of the corridor doors, and the natural leakage around the windows and the removal of the foul air through the seat and urinal vents will properly ventilate these rooms and prevent odors from passing up and into the building. In the floor of the first story are three rotating registers for rotating the air through the indirect radiators when the schools are not in session. The air for the foot-warmers is rotated from the corridor at all times. A vent is provided in each corridor, both corridors being vented into the same shaft. Direct radiation is provided in each vestibule. The warm -air flues to the class-rooms are 24 by 36 inches in cross-section, and enter the rooms eight feet above the floor through openings covered by a wire grill 36 by 30 inches. Each warm-air flue is fitted with a mixing-valve or damper for regulating the tem- perature of the incoming air. An adjusting damper is also provided for each warm-air flue for regulating the amount of air for each room, as this will vary accord- ing to the height of the flue or its location with regard to the prevailing winds. Each vent-flue, except the sanitary, is to be provided with a galvanized-iron damper for regulating the outflow of air. In each class-room vent-flue there is twenty square feet of radiat- ing surface of lj-inch steam-pipe made into the form and placed as indicated in the section showing the vent-flues. The vent from the recitation room is carried down and through a galvanized-iron duct (No. 24 gauge iron) on the basement ceiling to the brick vent-flue for this room, which should have twenty-five square feet of steam-pipe radiation, placed about on a level with the floor of the first story. Each sanitary vent has twenty square feet of the same kind of radiation. The building is to be heated by two horizontal tubular boilers of 27 horse-power each, and a cast-iron sectional boiler for heating the vent-flues when the larger boilers are not in use in moderately warm weather. These sectional boilers are generally designated " summer boilers." The boilers are to be so piped and valved that either or all of them can be used as desired. The recitation-room is to have 300, the two middle class- rooms 380, and the four corner class-rooms 400 square feet of cast-iron indirect radiation of twenty square feet per section, made into three sections for each stack, separately piped and valved, in order that the amount in use can be regulated according to the 162 THE SCHOOL HOUSE. weather. The vent-flue heaters are to be separately valved and piped. Hand bowls and faucets are provided in the first and second story corridors and cast-iron sinks in the boys' and girls' sanitary rooms, bowls and sanitary fixtures in the teachers' rooms in the second story. Mirrors are placed over the bowls and sinks for the pupils' use and in the teachers' toilets. Hose is to be provided for use in the basement. It is advisable to install a stand-pipe and hose in the basement and each corridor for use in case of fire. Sections are given showing the arrangement of the indirect radia- tors, mixing-valves and warm-air flues, the foul-air flues, heaters and dampers, adjusting dampers, rotating register and windows in the cold-air rooms, clothing racks and the catches for holding the chains for the mixing-damper and vent dampers. PLATE XXV. ' ' 1 1 1 [ * i [ [ [ i . i -Basement- ■iShowikcWlatiwcsVentilatiok' ■• 5 "" orrto ' -TIGHT RDM SCHOOL- THE SCHOOL HOUSE. 163 Plates XXV, XXVI, XXVII and XXVIII.— Plans for a two- story, eight-room, brick school building, showing the heating, ventilating and sanitary appliances. A combination of the gravity and mechanical systems of heating and ventilation is used. In the gravity system there are 400 square feet of indirect cast- iron heating surface for each school-room. This is divided into stacks of 100, 140 and 160 square feet for each class-room, separ- ately piped and valved, in order that either a part or the whole can be used as desired, and is sufficient to meet the requirements of heating and ventilation in the coldest weather that occurs in Massachusetts. Fresh air is admitted through the windows in the two cold-air rooms in the basement, when the gravity system is in use (the ducts PLATE XXVI. CLAtoRCJiH r-j ;;,';,, ;-i. •JLALC OPFCCT rpRiT 3TORY- •3H0W]NCrltAT!NG'«» , /£NTILATMK' 164 THE SCHOOL HOUSE. leading from the fan being then closed) in cold weather, when the difference between the inside and outside temperature is sufficient to furnish a full supply of warm, pure air by gravity flow. In the floor of the closet between the rooms on each side of the lower corridor there is a rotating register connecting with the cold- air rooms below. PLATE XXVII -oecohd story - --Eicht Room School- -Showing Meating ••.Ventilation ■■ In the basement of one of the corridor extensions there is also a supplementary means of supplying air by a fan driven by an electric motor, and 800 square feet of indirect cast-iron radiation, divided into sections of 100, 140 and 160 square feet, as in the other cold- air rooms. This part of the apparatus is intended to be used in moderate and calm weather, when the requisite supply of fresh air is not easily obtained by the gravity system without overheating, espe- cially in the spring and fall months. THE SCHOOL HOUSE. 165 When in use the windows leading from outside directly into the gravity cold-air rooms are to he closed, and the sliding damper at the entrance of the galvanized-iron ducts into the gravity cold-air rooms opened, the windows in the cold-air corridor extension base- ment opened and the fan run by the motor, the air either passing through the heated radiators, or, by means of a specially designed damper, going to the fan without passing the radiators. This PLATE XXVIII. OcctionThbouch E.B--I -.DEJAIl>rOR-HD\TlNC»YENTlWnNG--aCT!™--mRfWTH-c-C- ■E!GHT-R f 5)M-3CHOOL- damper can be used as a mixing damper to regulate the heat and allow more or less warm or cold air to pass the fan as may be desired. A four-inch diameter metallic thermometer, placed in the side of the galvanized-iron duct leading to the air rooms at the bottom of the warm-air flues, which go to the schoolrooms, will enable the janitor to regulate the temperature of the air sent from the fan. Should it be desired to use the fan when the air is colder than the fan radiation can properly warm, a portion of the radiation in the other cold-air rooms can be used to good advantage. By the use of this combination system forty cubic feet of air per minute can be supplied for each pupil under all conditions of temperature. 166 THE SCHOOL HOUSE. While it may add somewhat to the first cost of the building, the effective work will more than make up for the extra first cost. If electric power is not available, the fan may be run by an engine having a large diameter, low-pressure cylinder. This, how- ever, will require a change in the piping and setting up of this part of the apparatus, and a small boiler of sufficient size to run the PLATE XXIX. ., \V„ ,11 V ' « v n A\ "i . xU > „«■* - ''''III'' '•' iJ'^UrtWl iiiimf 'I'm .; BROCK AVE., 5CHO0er; NEW BEDFORD MASS.,U.SA. engine and also furnish (at a reduced pressure) steam for the vent- flue heaters when the larger boilers are not in use. In addition to the two horizontal tubular, a cast-iron sectional boiler is supplied for heating the vent -flues when the electric motor is used or when the larger boilers are not fired up. The warm-air flues and the vent-flues are of the same size and location, and similarly provided with dampers and heat, as pre- viously described for other school buildings. Sections are given showing cold-air rooms, indirect radiators, mixing-dampers and fan. Plates XXIX, XXX, XXXI and XXXII. — Perspective and plans for an eight-room schoolhouse. THE SCHOOL HOUSE. 1G7 This schoolhouse is in the city of New Bedford, C. Hammond and Sons being the architects, and is a two-story building con- structed of red brick with granite trimmings; the roof covered with black slate. It contains eight class-rooms and two teachers' rooms, also wide corridors and vestibules. In the basement are located play rooms and sanitary rooms for the pupils, a room for the janitor, boiler PLATE XXX. 'BASEMENT PLAN BROCK AVE., SCHOOL. NEW BEDFORD, MASS..U.5 -f and fuel rooms, together with fresh-air chambers and the indirect steam-heating radiators and boilers. The class-rooms are intended to accommodate 49 pupils and teacher, a total of 50. They are well lighted, the pupils' seats ami desks being so placed that the light is received from the left and rear. The blackboards are of best black slate. The teachers' rooms in the second story are provided with heat- ing radiators and toilet closets. The corridors are wide and well lighted, there being glass in the transoms over the doors and a large panel of heavy glass in each door leading from the class-rooms. 168 THE SCHOOL HOUSE. The walls of the corridors, staircase wings and vestibules are faced with selected smooth-cut brick. The vestibule floors are of tiles. The basement floor is of concrete, well rolled and smooth. The plastering is of Windsor cement, and steel lathing is used on ceil- ings and wooden partitions. The plastering on the brick walls is laid directly on the brick. PLATE XXXI. floor plan BROCK AVE..SCHOOL, F.RST FLOOR PLAN. NEW BEO p ORD#MASS . tU . s . A . The partitions around the stairways are provided with fire stops, as required by the Massachusetts building regulations. The conductors, gutters and flashings are of rolled copper. The inside finish of the first and second stories is of selected red oak, and the floors double, the upper floors being of the best rift yellow pine, not over three inches wide. In each corridor are clothes rails with bronzed hooks for holding the pupils' clothing. Electric call-bells and speaking-tubes are provided from each class-room to the principal's room, also to the janitor's room, and from the main entrance to the janitor's room. THE SCHOOL HOUSE. 1 69 The sanitary closets and urinals in the basement arc provided with automatic flushing tanks, a'nd arc well trapped and well ventilated into a special vent-flue which contains steam-pipes, to cause an outflow of foul air from the basement rooms and sanitary fixtures. In the first and second story is a galvanized-iron stand-pipe and 50 feet of hose for use in case of fire. Suitable hose racks are provided. PLATE XXXII. SECOND FLOOR plan. BROCK AVE SCHOOL, NEW BEDFORD. MASS.,U.SlA. In the basement, corridors and teachers' rooms are water faucets and hasins or howls well trapped. Two horizontal tubular boilers are provided for heating the building, each being 42 inches in diameter, 14 feet long, having 38 tubes three inches in diameter and 13 feet long. Each boiler is rated at 32 horse-power and tested to 150 pounds under hydraulic pressure. Safety-valves, automatic damper-regulator, steam-gauges, water- gauges, fusible plugs, blow-off cocks and all required valves are provided. 170 THE SCHOOL HOUSE. A supplementary sectional boiler of the rated capacity of 400 square feet is also provided for the vent-shaft heaters and for use in mild weather in the place of the main heating boilers. The piping for the vent-shaft heaters is so arranged that either or both main boilers or the sectional boiler may be used as desired. The piping in the building is what is known as the two-pipe system, with supply and return for each radiator or coil, and so adjusted that water-hammer or snapping is prevented during the circulation of the steam, and suitable allowance is made for expan- sion and contraction. The return pipes are not shown on the drawings, but generally follow the line of the supply pipes. Valves are provided by which part or the whole of the heating radiators may be used as desired. The fresh air for each class- room is warmed by being passed through cast-iron indirect radiators in the basement. Four hundred square feet of indirect radiation is provided for each class-room, and is divided into three sections or stacks, so that a part or the whole may be used as desired. In the teachers' rooms and corridors are direct radiators, and in the basement are lines of steam-pipes overhead. Radiators are also provided for bringing warm air up through two registers in the floor of the first-story corridor, the air being rotated from the corridor floor near the stairway extensions. These are designated as foot-warmers, and enable the pupils to warm their feet and hands and dry their clothing in cold, stormy weather. In the floor of the closets between the class-rooms in the first story are what are termed rotating registers, for use at night or when the rooms are not in use. The windows in the cold-air rooms and the dampers in the vent -flues being closed, the rotating registers are opened and air is drawn down from the class-rooms, passes through the indirect radiators and is returned to the class- rooms through the warm-air flues, thereby keeping the rooms warm and saving fuel. The warm fresh air is brought into the class-rooms through openings eight feet above the floor as shown in the drawings, and the vitiated air is removed through openings at the floor level, located as shown in the plans. The warm-air and foul-air flues are of brick, and well smoothed up on the inside. Each foul-air flue contains 20 square feet of steam-pipe heating surface for causing an outward flow of vitiated air, and is also provided with a curved damper of galvanized iron, operated by a chain and catch, by which the amount of air taken from the rooms THE SCHOOL HOUSE. 171 can be regulated or shut off when the rooms are not in use. In each warm-air flue is a galvanized-iron mixing-valve. There is also an adjusting damper by which the supply of fresh warm air to each room may he regulated or shut off if any room is not occupied. The direct radiation consists of vertical loop cast-iron radiators of an aggregate of 325 square feet of surface in corridors and teachers' rooms, and 280 square feet of surface of 1J inch steam- pipe in coils overhead, in the hasement. The indirect radiators for the foot-warmers consist of 100 square feet each of cast-iron radiators. At an inspection of this building the following conditions were found : Weather, fair ; wind north and moderate ; outside temperature, 21° F. ; outside relative humidity, 57 per cent; harometer, 30.32; average temperature of air at inlets to class-rooms, 87.1° F. ; average supply of fresh air through inlet to each class-room, in cuhic feet per minute, 2,337; average amount of air removed at outlet from each class-room, in cubic feet per minute, 2,984; average amount of air, in cubic feet per minute, supplied at inlet for seating capacity of each class-room, 47.7; average amount of air, in cubic feet per minute, removed through outlet in class-rooms, for each pupil, 60.9 ; greatest amount of air, in cubic feet per minute, supplied at inlet to any class-room, 3,247; least amount, 1,730 cubic feet; average difference in temperature in any room, taken at the same time at four places, at the breathing plane, 2° F. ; least difference at same points, .5° F. ; average temperature at teachers' desks, 69.5° F. Xo uncomfortable drafts could be perceived in the several rooms. Plates XXXIII, XXXIV and XXXV.— Plans for a small high or a grammar school — a two-story building constructed of yellow brick, with vellow terra-cotta trimmings and slated roof. If used as a grammar school the rooms intended for the chemical and physical laboratories can be used as class-rooms. In the first storv are four class, two recitation, and two teachers' rooms, with toilets connected. The corner rooms are 28 by 32 feet and 12 feet high, intended for forty-nine pupils. The recitation rooms are each 17 feet 8 inches by 28 feet. The teachers' rooms, including toilets, are each 11 feet 4 inches by 28 feet. The center corridor is 15 feet and the front corridor 12 feet wide. 172 THE SCHOOL HOUSE. THE SCHOOL HOUSE. 173 174 THE SCHOOL HOUSE. THE SCHOOL HOUSE. 175 In the second story are two class-rooms, a chemical and a physi- cal laboratory, each 28 by 32 feet by 12 feet high, an assembly hall 36 by 73 feet, and two storage-rooms in the stairway exten- sion. The stairways at each end of the building are six feet wide and railed on both sides. The main doors open both ways, as do also the assembly-room doors. In the basement, which is 12 feet high, except the boiler-room, which is 14 feet 6 inches in height, is a manual-training room, a boys' and a girls' recreation-room, sanitary rooms, boiler-room and coal-room, cold-air rooms and places for bicycles. Two stairways lead up to the first story and there are two doors from the outside to the stairway extension. The basement floor is of concrete, with a covering of Portland cement or rock asphalt. The interior walls and partitions are of brick, except between the tw r o recitation-rooms, on the corridor sides of the teachers' rooms, and the small storage -rooms in the second story. Between the rooms are closets with doors connecting with the class-rooms. All wooden partitions are lathed with expanded metal lathing, which is the only kind of lathing used throughout the building. Fire stops, which are required by the Massachusetts building laws in all school buildings, are also built. The walls of the corridors and stairway extensions have a face of good quality smooth brick, well laid and painted with light colored gloss paint but with no wood finish. Bookcases with glass doors are placed in each class-room between the heat and the vent -flues. The windows in the first and second story rooms have a double run of sash; the basement, stairway extension and corridor win- dows, single. The windows between the corridors and rooms are six feet aboye the floor, and each door, except to the store-rooms and teachers' rooms, has a center panel of heavy glass. There are windows over the doors leading to the front and end entrances. All inside'doors have glass transoms. The corridors in which clothing is to be hung have wooden hanging frames projecting one foot from the sides, with two pieces for hooks, the lower one nearest the wall and the upper one project- ing, with hooks alternating, to prevent the crowding of the clothing. In the basement of the stairway extensions are stands for bicycles, which are to be brought down a runway by the side of the base- ment steps. Gymnastic appliances are supplied in both boys' and girls' recreation rooms. 176 THE SCHOOL HOUSE. The manual-training room is fitted with lathes, grindstone, work-benches and tools. The chemical laboratory has tables, sinks, chemical closets with glass sliding doors, water, illuminating gas, electric power and the requisite apparatus. The physical laboratory is also supplied with the necessary tables and apparatus. The assembly hall has two large ceiling lights, connecting with skylights in the roof. The ceiling lights are fitted with roller-shade curtains. One of the ceiling lights and one skylight has a hinged section operated by chains and pulleys, which can be used for ven- tilation should the room become overheated in moderate weather. The building is heated by a low-pressure, two-pipe, gravity, steam system, with two horizontal tubular boilers, each 54 inches in diameter, 15 feet 3 inches long, containing 60 three-inch tubes 14 feet long; also by a smaller horizontal tubular boiler, 36 inches in diameter, 9 feet 3 inches long, containing 34 two-and-one-half- inch tubes, 8 feet long. This small boiler is intended to furnish steam for the steam-pipes in the vent-ducts and for a low-pressure engine to run the turning lathes, etc., in the manual-training room when the large boilers are not in use. It can also be used to warm the radiators in the spring and fall months, when but very little heat is required for a part of the day. The three boilers are set, piped, valved and connected so that either may be used as desired. When it is necessarv to use very low pressure in the larger boilers for warming the building in moderate weather, the small boiler can be used at higher pressure to run the engine for operating the lathes and also for heating the vent -fl vies. A reducing pressure-valve should be provided, also a separator, tank, pump, and pump governor. If an electric motor is used for running the lathes, it will not be necessary to use the pump, etc., the small boiler can be reduced in size and the system can be run by gravity return. This would be advisable where electric power is to be had. By having the boiler-room lower than the other parts of the basement a good return of water by gravity to the boiler is secured, and a complicated system of traps, pumps, etc., is rendered unnecessary. The supply and return pipes are of ample size, properly pitched, graded, dripped and valved, so as to secure a free and noiseless circulation and return to the boilers. The class-rooms, assembly hall, recitation rooms, laboratories and teachers' rooms are heated by stacks of indirect radiators of the H. B. Smith School Pin, Bundy Newport, American Sterling, or similar pattern, placed in the cold-air rooms in the basement ; THE SCHOOL HOUSE. 177 each stack being divided into three sections so that part or the whole may he used as desired. Direct radiation is supplied in the corridor and stair extensions, and two lines of onc-and-one-quarter inch steam-pipe under the clothing racks in the corridors for drying in storm} weather and tor heating in extremely cold weather. At each end of the lower corridor there are floor registers without valves for use as foot-warmers, the air being drawn down through the register nearest the door, passing through the stack of radiators, which are to be cased with galvanized iron and suspended from the basement ceiling, and coming -up through the register farthest from the door. Good exhaust Hues are provided from the corridors, and the leakage of air into the corridors is sufficient to keep them in good condition. in the chemical and physical laboratories four lines of one-and- one-quarter-inch steam-pipe should be placed on the two exposed sides, to be used at night to prevent freezing in extremely cold weather when the rooms are not in use. Direct radiation is placed in the assembly hall in addition to the indirect, to keep the room partly warmed and to heat quickly when the indirect is turned on before the room is occupied. When occupied the direct should be shut off and only the indirect used. The manual-training room in the basement is also supplied with direct and indirect radiation. The recreation rooms and sanitary rooms are warmed by lines of overhead steam-pipes, the supply mains in the basement being protected by non-heat-conducting pipe covering. The ceiling of the boiler-room and the cold-air rooms are specially protected by non-heat-conducting material placed between the flooring and the metallic lathing — in the case of the boiler- room, to prevent the heat passing up through the floor and over- heating the rooms above, which often happens when the boilers are located under the school-room and no protection is provided other than the wooden floors. It is advisable to construct the ceil- ing of iron beams and terra-cotta arches and make the boiler-room fire-proof. If the cold-air rooms are not protected overhead the cold air chills the floor directly over them, sometimes to an uncomfortable degree in extremely cold weather. The cold-air room windows should be hung in two parts and be provided with cords and pulleys for opening and closing. 178 THE SCHOOL HOUSE. The fresh warm air is taken into the rooms through inlets of the same size and location as previously described in other plans. The dimensions of each of the four warm-air flues for the assembly hall are 52 by 24 inches. Tests of the best work show that by having the warm-air flues of liberal size the air is introduced into the rooms at a lower velocity and temperature than when the flues are too small. In moderate weather this is a decided advantage, as a sufficient amount of fresh air can be supplied without overheating the room, as was the case in some of the earlier work, where the temperature had to be raised too high for comfort in order to obtain the required volume of air with small ducts. In some cases, especially where fans or blowers have been used, the ducts have been reduced in size under pretense of cheapening the cost of construction, and the air forced into the room at a high velocity, causing uncomfortable drafts and a needless expenditure of power. Wire grills are used instead of cast-iron registers to cover the inlets and outlets. Mixing valves are supplied for warm-air flues. Adjustable galvanized-iron cut-offs or adjusting dampers are pro- vided at the bottom entrance for the warm air to regulate the supply of air to the several rooms under the varying conditions of wind and temperature or to cut off the supply from any unoccupied room . The use of double windows will be of great service in very cold and windy weather, and will to a considerable extent prevent too rapid cooling and precipitation of the air by the glass surface which often causes downward drafts in front of single windows. A considerable saving of fuel can be made by using double windows. The openings from the rooms and corridors into the vent -flues are of the size and location previously described in other plans. Galvanized-iron dampers are also provided for these vent openings. Vent-flue heaters are installed. By the use of steam-pipes or radiators in the vent -flues a good velocity is given to the outgoing foul air, back draft is prevented without the use of flap-valves, whose chief purpose appears to be to obstruct the outflow of the foul air and to cause a disagreeable noise by flapping up and down when moved by the wind. Experience and not theory has taught that means should always be provided for causing an outflow of the foul air through the vent- flues and ducts, either by heat or mechanical means. Attempts to cause an outflow by other methods, especially when the outlets are THE SCHOOL HOUSE. 179 obstructed by worse than useless flexible valves, which are liable to close when the room is occupied and ventilation required, and to open when the room is unoccupied and no ventilation needed, usually result in noticeable failures, as proved by numerous tests. With these contrivances there appears to be no practicable way of adjusting the outflow, and in extremely cold and windy weather, when the outflow will need checking, the flap-valves will be open to their full capacity ; but in mild and calm weather, when they should be wide open, they are liable to be closed. The sanitary closets are of a pattern having an especially large local vent (four inches in diameter) and each closet is vented into an underground duct running to the smoke-flue surrounding the iron smoke-pipe from the boilers. Each closet has an automatic flush. The divisions or par- titions between the closets are raised eight inches above the floor on metal standards, which allows the janitor to use w'ater liber- ally for washing the floor through a hose furnished for that purpose. Each line of closets is connected with a well -vented and trapped soil-pipe. The urinals are fitted with a perforated flushing-pipe, and have a liberal vent connected with the main closet vent-duct. The discharge pipe should be well trapped and vented. The sanitary -rooms are ventilated through the closets and urinals to the space around the boiler smoke-pipe. All plumbing should be of the open or exposed pattern and all fixtures w T ell trapped and vented. Plates XXXVIII and XXXIX are designs by the late John T. White, the friend and companion inspector of the writer for eighteen years. Plate XXXVIII. — Design for a direct -indirect radiator. This radiator is designed to be used in small halls or in churches, where it may be easy to provide for a strong exhaust leg of a venti- lating system, but difficult to arrange for a straight indirect method of heating and supplying air. Almost any good direct radiator may be used or a coil of pipe. The radiator is first cased in metal, and may then be finished in wood in any way desired. The fresh-air opening has an area of two square inches for each square foot of radiation; but the supply of air from outside may be controlled by damper, as shown, which can be held in any position. The inside damper is always to be entirely open or shut. When 180 THE SCHOOL HOUSE. 1DWU aavog THE SCHOOL HOUSE. 181 open, the air is taken from the room, and the effect is, of course, nearly the same as with a direct radiator. Such a radiator with 100 square feet of surface has been found to furnish 500 cubic feet of air per minute under fairly favorable conditions. PLATE XXXVII. SANITARY BUILDING The fresh-air opening, extending nearly the entire length of the stack, gives a more even distribution of air to the heating surface than (as is generally the case) where the opening is near the center of the stack and the area is obtained by one which is high and short instead of low and long, as shown in this design. 182 THE SCHOOL HOUSE. PLATE XXXVIII. Dan per Controller • No Scale • top of Floor. \ Section •Pla n 5c ALE 1 1 I 1 1 I I I I I I I I One Foot ■Design for Direct-Indirect Radiator. THE SCHOOL HOUSE. 183 Plate XXXIX. — Design for setting a portable furnace, showing a method of setting a portable furnace in a small hall or in a church, where the registers are necessarily placed in the floor. PLATE XXXIX. ROTATING REGISTER REGISTER feffiW ^v' mrnn FURNACE - SHOWING MIXING VALVF. REGISTER OVER In such cases, when the room is too warm, the usual remedy is to close the register and thus shut off the supply of air, throwing all the heat back on the furnace, increasing the danger from fire and possible injury to the pipes and castings. The registers here shown have no valves, and the temperature of the incoming air is regulated by a mixing-valve in each duct as shown. 184 THE SCHOOL HOUSE. There is a damper for controlling the supply of outside air, and a rotating damper is provided. The cold-air and warm-air ducts are much larger than those generally installed. There is a pit under the furnace about two feet deep — -an essential feature for good work. If any small rooms are to be heated, branches can be taken from the large pipes with switch dampers to control the flow of air. PLATE XL. CORRIDOR FOOT-WARMER Plate XL. — Foot-warmers to be placed in schoolhouse corridors. Six sections of indirect cast-iron pin radiators are made into a stack containing 120 square feet of radiating surface, which is suspended below the basement ceiling on two 1-J-inch iron pipes, which are secured to the floor timbers above by iron hangers. The sections are 15£ inches high at their highest part and 36 inches long. The pins are one inch long and the sections are set up four inches on centers with one-half inch space between the ends of the pins. Two-inch right-and-left nipples are used for connecting the sections, which are tapped for two-inch supply and return. A f-inch air-valve is placed in the quarter-turn or elbow of the return. This air-valve is placed in a position, where, should it be desirable to moisten the air, a small quantity of steam may be allowed to escape through the air-valve. THE SCHOOL HOUSE. 185 The casing is of twenty-four gauge galvanized iron put together with screws, nuts and angle iron, so that it may he easily removed should it he required to make repairs on the heating-stack. In the hottom of the casing are two clean-out slides for removing any dirt or substance that may fall through the register gratings in the floor of the corridor. The air is taken from the corridor down on one side, passes under and up through the radiator-stack and ascends to the corridor through another register in the corridor floor. This arrangement prevents the accumulation of dirt and various substances that would fall on the heated radiators through a register placed directly above the heating stack. Covering Boilers. Covering boilers by the use of sand is not advisable, because if cracks appear in the setting, the sand will deposit in the cracks when the wall is heated and will continue to doso and widen the cracks. When a boiler is arched over with bricks, care should be taken that the arch does not rest on the boiler, and that at least an inch space is left between the boiler and the brick arch, which should be self-supporting. An eightv-five per cent magnesia covering when properly applied makes a very desirable non-heat-conducting protection over the boiler and gives very satisfactory results. The practice of leaving a space completely bricked in around the boiler to gain additional heating surface is now but seldom resorted to, as the tendency is to burn out that part of the boiler above the water line. The returning of hot gases from the uptake, across the top of the boiler is another defect, as its efficiency is of doubt- ful value. Another practice not to be recommended, is that of continuing the boiler walls above the boiler for the purpose of obtaining a space above the boiler for heating air for ventilation, by utilizing the heat escaping through the boiler covering. Should cracks be made in the setting or covering, there is danger of the unconsumed gases passing into and contaminating the air intended for ven- tilation. With this setting the fireman or engineer is obliged to crawl through a door and over the boiler to reach either the steam or safety-valve, and in case of the safety-valve blowing off to relieve too high pressure, the steam is carried by the warm air ducts into 186 THE SCHOOL HOUSE. the school or other rooms which receive their air from this source, and possibly causing excitement or a panic among the pupils. Plates XLI, XLII, XLIII and XLIV. — Settings for horizontal tubular boilers. Designed and recommended by the Hartford Boiler Inspection and Insurance Company. Q--- 1 't^zQ Q -j fcf THE SCHOOL HOUSE. 187 < H y< o N 5 X w o t, M en o O H O H M M Q P H 55 O 188 THE SCHOOL HOUSE. PLATE XLIII. Cross Section of Setting for One Horizontal Tubular Boiler. THE SCHOOL HOUSE. 189 o pq « « H H o N 5 o X o ? H a o TABLE 15. (APPROXIMATE) AREAS Inches 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 10 .69 .76 .83 .9 .97 1.04 l.ll 1.18 1.25 1.31 1.38 1.45 1.52 1.59 1.66 1.73 1.8 1.8 11 .76 .84 .91 .99 1.06 1.14 1.22 1.29 1.37 1.45 1.52 1.6 1.68 1.75 1.83 1.9 1.98 2.0 12 .83 .91 1. 1.08 1.16 1.25 1.33 1.41 1.5 1.57 1.66 1.75 1.83 1.91 2. 2.08 2.16 2.2 13 .9 .99 1.08 1.17 1.26 1.35 1.44 1.53 1.62 1.71 1.8 1.89 1.98 2.07 2.16 2.25 2.34 2.4 14 .97 1.06 1.16 1.26 1.36 1.47 1.55 1.65 1.75 1.84 1.94 2.04 2.13 2.23 2.33 2.43 2.52 2.6 15 1.04 1.14 1.25 1.35 1.47 1.56 1.66 1.77 1.87 1.97 2.08 2.18 2.29 2.39 2.5 2.6 2.7 2.8 16 1.11 1.22 1.33 1.44 1.55 1.66 1.77 1.88 2. 2.11 2.22 2.33 2.44 2.55 2.66 2.77 2.88 3. 17 1.18 1.29 1.41 1.53 1.65 1.77 1.88 2. 2.12 2.24 2.36 2.47 2.59 2.71 2.83 2.95 3.07 3.11 18 1.25 1.37 1.5 1.62 1.75 1.87 2. 2.12 2.25 2.37 2.5 2.62 2.75 2.87 3. 3.12 3.25 3.3' 19 1.31 1.45 1.57 1.71 1.84 1.97 2.11 2.24 2.37 2.5 2.63 2.77 2.9 3.03 3.16 3.29 3.43 3.51 20 1.38 1.52 1.66 1.8 1.94 2.08 2.22 2.36 2.5 2.63 2.77 2.91 3.05 3.19 3.33 3.47 3.61 3.7! 21 1.45 1.6 1.75 1.89 2.04 2.18 2.33 2.47 2.62 2.77 2.91 3.06 3.2 3.35 3.5 3.64 3.7 3.91 22 1.52 1.68 1.83 1.98 2.13 2.29 2.44 2.59 2.75 2.9 3.05 3.2 3.36 3.51 3.66 3.81 3.97 4.15 23 1.59 1.75 1.91 2.07 2.23 2.39 2.55 2.71 2.87 3.03 3.19 3.35 3.51 3.67 3.83 3.99 4.15 4.3 24 1.66 1.83 2. 2.16 2.33 2.5 2.66 2.83 3. 3.16 3.33 3.5 3.66 3.83 4. 4.16 4.33 4.5 25 1.73 1.9 2.08 2.25 2.43 2.6 2.77 2.95 3.12 3.29 3.47 3.64 3.81 3.99 4.16 4.34 4.51 4.6* 26 1,8 1.98 2.16 2.34 2.52 2.7 2.8 3.07 3.25 3.43 3.61 3.7 3.97 4.15 4.33 4.51 4.69 4.81 27 1.87 2.06 2.25 2.43 2.62 2.81 3. 3.18 3.33 3.56 3.75 3.93 4.12 4.31 4.5 4.68 4.87 5.0( 28 1.94 2.13 2.33 2.52 2.72 2.91 3.11 3.3 3.5 3.69 3.88 4.08 4.27 4.47 4.66 4.86 5.05 5.25 29 2.01 2.21 2.4 2.61 2.81 3. 3.22 3.42 3.62 3.82 4.02 4.22 4.43 4.63 4.83 5.03 5.23 5.43 30 2.08 2.29 2.5 2.7 2.9 3.12 3.33 3.54 3.75 3.95 4.16 4.37 4.58 4.79 5. 5.2 5.41 5.62 31 2.15 2.36 2.58 2.79 3.01 3.22 3.44 3.66 3.87 4.09 4.3 4.52 4.73 4.95 5.16 5.38 5.45 5.81 32 2.22 2.44 2.66 2.88 3.11 3.33 3.55 3.77 4. 4.22 4.44 4.66 4.88 5.11 5.33 5.55 5.77 6. 33 2.29 2.52 2.75 2.97 3.2 3.43 3.66 3.89 4.12 4.35 4.58 4.81 5.04 5.27 5.5 5.72 5.95 6.18 31 2.36 2.59 2.83 3.06 3.3 3.54 3.77 4. 4.25 4.48 4.72 4.95 5.19 5.43 5.66 5.9 6.13 6.37 35 2.43 2.67 2.91 3.15 3.4 3.64 3.88 4.13 4.37 4.61 4.86 5.1 5.34 5.59 5.83 6.07 6.31 6.56 36 2.5 2.75 3. 3.25 3.5 3.75 4. 4.25 4.5 4.75 5. 5.25 5.5 5.75 6. 6.25 6.5 6.75 37 2.56 2.82 3.08 3.34 3.59 3.85 4.11 4.36 4.62 4.88 5.13 5.39 5.65 5.9 6.16 6.42 6.68 6.93 38 2.63 2.9 3.16 3.43 3.69 3.95 4.22 4.48 4.75 5.01 5.27 5.54 5.8 6.06 6.33 6.59 6.86 7.12 39 2.7 2.97 3.25 3.52 3.79 4.06 4.34 4.6 4.87 5.14 5.41 5.68 5.95 6*.22 6.5 6.77 7.04 7.24 40 2.77 3.05 3.33 3.61 3.88 4.16 4.44 4.72 5. 5.27 5.55 5.83 6.11 6.38 6.66 6.94 7.22 7.5 41 2.84 3.13 3.41 3.7 3.98 4.27 4.55 4.84 5.12 5.4 5.69 5.97 6.26 6.54 6.83 7.11 7.4 7.68 42 2.91 3.2 3.5 3.79 4.08 4.37 4.66 4.95 5.25 5.54 5.83 6.12 6.41 6.7 7. 7.29 7.58 7.87 43 2.98 3.28 3.58 3.88 4.18 4.47 4.77 5.07 5.37 5.67 5.97 6.29 6.56 6.86 7.16 7.46 7.76 8.06 44 3.05 3.36 3.66 3.97 4.27 4.5S 4.88 5.19 5.5 5.8 6.11 6.41 6.72 7.02 7.33 7.63 7.94 8.25 45 3.12 3.43 3.75 4.06 4.37 4.68 5. 5.31 5.62 5.93 6.25 6.56 6.87 7.18 7.5 7.81 8.12 8.43 DIMENSIONS IN INCHES. AREAS IN SQUARE FEET. OF RECTANGULAR OPENINGS. 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 Inches 1.94 2.01 2.08 2.15 2.22 2.29 2.36 2.43 2.5 2.56 2.63 2.7 2.77 2.84 2.91 2.98 3.05 3.12 10 2.13 2.21 2.29 2.36 2.44 2.52 2.59 2.67 2.75 2.82 2.9 2.97 3.05 3.13 3.2 3.28 3.36 3.43 11 2.33 2.4 2.5 2.58 2.66 2.75 2.83 2.91 3. 3.08 3.16 3.25 3.33 3.41 3.5 3.58 3.66 3.75 12 2.52 2.61 2.7 2.79 2.88 2.97 3.06 3.15 • 3.25 3.34 3.43 3.52 3.61 3.7 3.79 3.88 3.97 4.06 13 2.72 2.81 2.9 3.01 3.11 3.2 3.3 3.4 3.5 3.59 3.69 3.79 3.88 3.98 4.08 4.18 4.27 4.37 14 2.91 3. 3.12 3.22 3.33 3.43 3.54 3.64 3.75 3.85 3.95 4.06 4.16 4.27 4.37 4.47 4.58 4.68 15 3.11 3.22 3.33 3.44 3.55 3.66 3.77 3.88 4. 4.11 4.22 4.34 4.44 4.55 4.66 4.77 4.88 5. 16 3.3 3.42 3.54 3.66 3.77 3.89 4. 4.13 4.25 4.36 4.48 4.6 4.72 4.84 4.95 5.07 5.19 5.31 17 3.5 3.62 3.75 3.87 4. 4.12 4.25 4.37 4.5 4.62 4.75 4.87 5. 5.12 5.25 5.37 5.5 5.62 18 3.G9 3.82 3.95 4.09 4.22 4.35 4.48 4.61 4.75 4.88 5.01 5.14 5.27 5.4 5.54 5.67 5.8 5.93 19 3.88 4.02 4.16 4.3 4.44 4.58 4.72 4.86 5. 5.13 5.27 5.41 5.55 5.69 5.83 5.97 6.11 6.25 20 4.08 4.22 4.37 4.52 4.66 4.81 4.95 5.1 5.25 5.39 5.54 5.68 5.83 5.97 6.12 6.29 6.41 6.56 21 4.27 4.43 4.58 4.73 4.88 5.04 5.19 5.34 5.5 5.67 5.8 5.95 6.11 6.26 6.41 6.56 6.72 6.87 22 4.47 4.63 4.79 4.95 5.11 5.27 5.43 5.59 5.75 5.9 6.06 6.22 6.38 6.54 6.7 6.86 7.02 7.18 23 4.66 4.83 5. 5.16 5.33 5.5 5.66 5.83 6. 6.16 6.33 6.5 6.66 6.83 7. 7.16 7.33 7.5 24 4.86 5.03 5.2 5.38 5.55 5.72 5.9 6.07 6.25 6.42 6.59 6.77 6.94 7.11 7.29 7.46 7.63 7.81 25 5.05 5.23 5.41 5.45 5.77 5.95 6.13 6.31 6.5 6.68 6.86 7.04 7.22 7.4 7.58 7.76 7.94 8.12 26 5.25 5.43 5.62 5.81 6. 6.18 6.37 6.56 6.75 6.93 7.12 7.24 7.5 7.68 7.87 8.06 8.25 8.43 27 5.44 5.63 5.83 6.02 6.22 6.4 6.61 6.8 7. 7.19 7.38 7.58 7.77 7.97 8.16 8.36 8.55 8.75 28 5.63 5.84 6.04 6.24 6.44 6.64 6.84 7.04 7.25 7.45 7.65 7.8 8.05 8.25 8.45 8.65 8.86 9.06 29 5.83 6.04 6.25 6.45 6.66 6.87 7.08 7.29 7.5 7.7 7.91 8.12 8.33 8.54 8.75 8.95 9.16 9.37 30 6.02 6.24 6.45 6.67 6.88 7.1 7.31 7.53 7.75 7.96 8.18 8.39 8.61 8.82 9.04 9.25 9.47 9.68 31 6.22 6.44 6.66 6.88 7.1 7.33 7.5") 7.77 8. 8.22 8.44 8.66 8.88 9.11 9.33 9.55 9.77 10. 32 6.4 6.64 6.87 7.1 7.33 7.56 7.7!) 8.02 8.25 8.47 8.7 8.93 9.16 9.39 9.62 9.85 10.08 10.31 33 6.61 6.84 7.08 7.31 7.55 7.79 8.02 8.26 8.5 8.73 8.97 9.2 9.44 9.68 9.91 10.15 10.38 10.62 34 8.8 7.04 7.29 7.53 7.77 8.02 8.26 8.5 8.75 9. 9.23 9.47 9.72 9.89 10.2 10.45 10.69 10.93 35 7. 7.25 7.5 7.75 8. 8.25 8.5 8.75 9. 9.25 9.5 9.75 10. 10.25 10.5 10.75 11. 11.25 36 ;.\'.> 7.45 7.7 7.96 8.22 8.47 8.73 9. 9.25 9.5 9.76 10.02 10.27 10.5;; 10.79 11.04 1 1 .3 11.56 37 JM 7.65 7.91 8.18 8.44 8.7 8.97 9.23 9.5 9.76 10.02 10.29 10.55 10.81 11. OS 11.34 11.61 11.87 38 r.58 7.8 8.12 8.39 8.66 8.93 9.2 9.47 9.75 10.02 10.29 10.56 10.83 11.1 11.37 11.64 11.91 12.11 39 : .77 8.05 8.33 8.61 8.88 9.16 9.44 9.72 10. 10.27 10.55 10.83 11.11 11.38 11.66 11.94 12.12 12.5 40 r .97 8.25 8.54 8.82 9.11 9.39 9.68 9.89 10.25 L0.53 10.81 11.1 11.38 11.67 11.95 L2.24 12.52 12.81 41 !.16 8.45 8.75 9.04 9.33 9.62 9.91 10.2 10.5 in.::) 11.08 11.37 11.66 11.95 12.25 12.54 12.83 L3.12 42 ;.:',6 8.65 8.95 9.25 9.55 9.85 10.15 L0.45 10.75 11.04 11.34 11.64 11.94 12.24 12.54 12.84 L3.13 13.43 43 :.55 8.86 9.16 9.47 9.77 10.08 10.38 10.69 11. 11.3 11.61 11.9 J 12.12 12.52 12.83 13.13 13.44 13.75 44 .75 ...... 9.06 9.37 9.68 10. 10.31 10.62 10.93 11.25 11.56 11.87 12.11 12.5 12.81 13.12 L3.43 1."..:;. 14.06 45 NO DEDUCTION HAS BEEN MADE HERE FOR REGISTERS OR GRILLS. 102 THE SCHOOL HOUSE. TABLE 16. Areas and Circumference of Circles. Circum- Circum- Circum- Diam. Area. ference. Diam. Area. ference. Diam. Area. ference. In. Sq. Ft. Ft. In. Sq. Ft. Ft. In. Sq. Ft. Ft. 1 .0055 .2618 29 4.587 7.592 57 17.72 14.92 2 .0218 .5236 30 4.909 7.854 58 18.35 15.18 3 .0491 .7854 31 5.241 8.116 59 18.99 15.45 4 .0873 1.047 32 5.585 8.378 60 19.63 15.71 5 .1364 1.309 33 5.940 8.639 61 20.29 15 97 6 .1964 1.571 34 6.305- 8.901 62 20.97 16.23 7 .2673 1.833 35 6. £81 9.163 63 21.65 16.49 8 .3491 2.094 36 7.069 9.425 64 22.34 16.76 9 .4418 2.356 37 7.467 9.686 65 23.04 17.02 10 .5454 2.618 38 7.876 9.948 66 23.76 17.28 11 .6600 2.880 39 8.276 10.21 67 24.48 17.54 12 .7854 3.142 40 8.727 10.47 68 25.22 17.80 13 .9218 3.403 41 9.168 10.73 69 25.97 18.06 14 1.069 3.665 42 9.621 10.99 70 26.73 18.33 15 1.227 3.927 43 10.08 11.26 71 27.49 18.59 16 1.396 4.189 44 10.56 11.52 72 28.27 18.85 17 1.576 4.451 45 11.04 11.78 73 29.07 19.11 18 1.767 4.712 46 11.54 12.04 74 29.87 19.37 19 1.969 4.974 47 12.05 12.30 75 30.68 19 63 20 2.182 5.236 48 12.57 12.57 76 31.50 19.90 21 2.405 5.498 49 13.10 12.86 77 32.34 20.16 22 2.640 5.760 50 13.64 13.09 78 33.18 20.42 23 2.885 6.021 51 14.19 13.35 79 34.04 20.68 24 3.142 6.283 52 14.75 13.61 80 34.91 20.94 25 3.409 6.545 53 15.32 13.88. 81 35.78 21.21 26 3.687 6.807 54 15.90 14.14 82 36.67 21.47 27 3976 7.069 55 16.50 14.40 83 37.57 21.73 28 4.276 7.330 56 17.10 14.66 84 38.48 21.99 THE SCHOOL HOUSE. 198 ^ & ^ -S ^ * 8 5^ § ^ /co CM *! / / CO CM ". •* ^ 2 ? • / • -. r. CM u «) )> .« 1! .« / the interse heavy figun 'at the large For exampi h air (frictio g at the int marked 14. ' / O •-■ ■g / M - - - T ' CM / 4 -r ' « OS C5 CO s s / _° _ _: — C4 CM K — _ g [s, ^ "■. S Nj .! i. / / 'us "* '_- X — OS CI O x> p. / - - - - Tl tl ;: " ~ O ' 1^ § <* c - -• .r. "M 119 — ( r~ r~ P- 1-1 < Q / - - - ~ Sfl •m " X -* 10 CD '« H< h. c CO cs - .- K ,, OO - / ~ ~ - ■ ; ' "' 04 '' OS ~ 10 -" K <| / H ' N cc — ■0 / — — — (N 71 Cl 95 -■■ « ■-; X - y /- a / .ft CO c , EC - — „ A p. _- ■..- 1-1 / - _ "" — N Ci 91 CO ° ~ ■ - " DC - ZJ p, / .- _ -- CO r , at CO - ,. -, Cl a / - - - * ■O CD SO rl - 5 g fa ' / p. 7, X ■*« H CO f . UJ 1- X so / CO - - cn. IN CO — ■*■ •A OS " X 93 OS -' X / - — _ p. p. ,- 99 CJ t» 93 CO O -+ CO c^ cr / ~ ' _ ' " t _ x - la 1- r . 93 - / CO •"' cm SN 00 "* "" CO X ga 2 5 03 CO e ? ' tl c: OS m « / gg M 93 p. 3 - IS - iO»8qODSlO-*NrtON OWCDO-*WN®OCOt~HlOO)N® HIOO'*00»NH(00'*!»MNrHO NO0)l>l0'>*eilHffl00!0'*W'-iO00 O oooooooooooooooo iOO>OOiOOWOiOO»QO>00»00 HTi<»00H05ie00O(MlftNO)N'*N 00 K5'*C(J(NHO0)00StD>0'*ei5IN'HO ©-icr.l(5NC!0«'*ffiCCOIN'*»CO i-H F-i i-H i— lnoqNN(MNX»«ICOM CO 0-*COCNICOO"* , OOCMCDO^fOOCM«CO lOOiOOlCOlOO»OO0MOlOOlOO NSlOlNCOlOOCOffl-HN-tloSXO lO CO CO * X CO O0 »,00 0OOOGO0O0OQ00CCO OJCOt-rtiOOMI^rtioOSWt-'-iloc; tOOCONOMNOTft-O^t-H^N i— IHHH- 1 f-i i- 1 CN OM<005N10COH+KO ®'Ht^cqi>m»a500'*0)tC'Ooe t-CiO«M10CDC005rnjq-t®l>030 K^yTco" aTo — < cn co"-^co o^ccafo hm" CO ON-ttOCOOCO^fflcOON-fCOCOO OOOOJCBOIOIOJXOOMCOCOKCOCO -^HCO"ON©tDMONT)i-OOiON »OOOJS(MNH©-tOO*O^CJ1< NO0St»(B*WHO.00t->8'( l NOffi tH >0 lO CO t-^acf (jTo ■— ~ t-T ovf CO ^ lO CO tC tH OOOOOOOOOOOOOOOO 10 50KCOO)0-iWCO-*lO»NCO»0 »^ThlO!Ot»t>COO)OiOH«N»'* O >0 0»OOiOO>OOiOO>OOiOOiOO N-H35C0010CONOO; NtD-#M-iO WCO-t^iOiOOt-SOOMSfflOHH r-l rH »-H OJ oiooioomo>oo»oo>coiraoo BlOraOWlOWOCOOCOOOOWHO) COCOMOONNN^HOHfflOlOO-* CO «50>OOlOO»OOlCO>OOlOOiOO NK3INOMOMOt»lO«CNlOINO 05N!0OC0NHlO00(NfflOCl5l>Hl0 t- O00a-*HOOO!0'*NOCC!0'*NO ■*NHOO00ffll0tC0(NOffl00N!0 Tft-OCClOOOr-i^t-OCOfflOOH^t- co OOOOOOOOOOOOOOOO O^OOaOH(NM-*lO!ON00050H ON^!OfflH«10^ON lO cocoNt-cqOHOoiooiooi^oico Q " fa letoNooa-.o-NM-fioco^coojo THE SCHOOL HOUSE. 195 TABLE 19. Capacity of Pipes and Registers. ROUND PIPES. Diameter Area in Diameter Area in Diameter Area in of Pipe Sq. Inches. of Pipe. Sq. Inches. of Pipe. Sq. Inches. 7 in. 38 12 in. 113 22 in. 380 8 in. 50 14 in. 154 24 in. 452 9 in. 63 16 in. 201 20 in. 531 10 in. 78 18 in. 254 28 in. 616 11 in. 95 20 in. 314 30 in. 707 REGISTERS. Size of Capacity in Size of Capacity in Size of Capacity in Sq. Inches. Opening. Sq. Inches. Opening. Sq. Inches. Opening. 6X10 40 10X14 93 20X20 267 8X10 53 10X16 107 20 X 24 320 8X12 64 12X15 120 20X26 347 8X15 80 12X19 152 21X29 406 9X12 72 14X22 205 27X27 486 9X14 84 15X25 250 27X38 684 10X12 80 16X24 256 30X30 600 ROUND REGISTERS. 1 Size of Opening. Capacity in Sq. Inches. Size of Opening. Capacity in Sq. Inches. Size of Opening. Capacity in Sq. Inches. 7 in. 8 in. 9 in 10 in. 26 33 42 52 12 in. 14 in. 16 in. 18 in. 75 103 134 169 20 in. 24 in. 30 in. 36 in. 209 301 471 679 DIMENSIONS OF CAST-IRON REGISTERS. (TUTTLE AND BAILEY.) Size. Inches. 10X12 10X14 10X16 12X15 12X16 12X19 14X18 14X22 15X25 16X16 16X20 16X21 Net Area. Square Feet. .55 .64 .74 .83 .88 1.05 1.16 1.42 1.73 1.18 1.48 1.55 Size. Inches. 16X24 16X26 18X24 18X30 20X20 20X24 20X26 21X29 24X32 27X27 27X38 30X30 Net Area. Square Feet. 1.77 1.92 2.00 2.50 1.85 2.22 2.41 2.82 3.55 3.37 4.75 4.16 196 THE SCHOOL HOUSE. TABLE 20. Weights of and Q Steel per Lineal Foot (Based o?i 489.6 lbs. fer cubic foot.) Size. Wt. of • Wt. of ■ Size. Wt. of # Wt. of ■ Size. Wt. of • Wt.ofH Inches. 1 ft. long 1 ft. long. Inches. 1 ft. long 1 ft. long Inches 1 ft. long. 1ft. long. 0ft .0026 .0033 3 24.03 30.60 6 96.14 122.4 oft .0104 .0133 3ft 25.04 31.89 eft- 98.14 125.0 04 .0417 .0531 H 26.08 33.20 el 100.2 127.6 oft .0938 .1195 3ft 27.13 34.55 6ft 102.2 130.2 01 .1669 .2123 H 28.20 35.92 6j 104.3 132.8 oft .2608 .3333 °1 6 29.30 37.31 6-5- °1 6 106.4 _ 135.5 OS .3756 .4782 H 30.42 38.73 6 a u 8 108.5 138.2 Oft .5111 .6508 3ft 31.56 40.18 eft- 110.7 140.9 oi .6676 .8500 H 32.71 41.65 ei 112.8 143.6 0ft .8449 1.076 d 16 33.90 43.14 "in 114.9 146.5 0| 1.043 1.328 3 A '8 35.09 44.68 6£ 117.2 149.2 OH 1.262 1.608 Q1X °16 36.31 46.24 Hh' 119.4 152.1 of 1.502 1.913 3f 37.56 47.82 6* 121.7 154.9 oil 1.763 2.245 Sit 38.81 49.42 611 123.9 157.8 o& 2.044 2.603 °8 40.10 51.05 «s 126.2 160.8 rU-5 2.347 2.989 3l6 41.40 52.71 oil 12S. 5 163.6 1 2.670 3.400 4 42.73 54.40 7 130.9 166.6 1ft 3.014 3.838 4ft 44.07 56.11 n 135.6 172.6 li 3.379 4.303 41 45.44 57.85 71 140.4 178.7 1ft 3.766 4.795 4ft 46.83 59.62 n 145.3 184.9 H 4.173 5.312 4| 48.24 61.41 n 150.2 JL91.3 ift 4.600 5.857 4ft 49.66 63.23 u 155.2 197.7 if 5.019 6.428 4| 51.11 65.08 n 160.3 204.2 ift 5.518 7.026 A..1- *16 52.58 66.95 7 L ' 8 165.6 210.8 li 6.008 7.650 4-L *2 54.07 68.85 8 171.0 217.6 1-2- L l 6 6.520 8.301 4ft 55 59 70.78 «1 176.3 224.5 l| 7.051 8.978 4f 57.12 72.73 81 181.8 231.4 iH 7.604 9.682 *tt 58.67 74.70 8| 187.3 238.5 if 8.178 10.41 44 60.25 76.71 81 193.0 245.6 1 16 8.773 11.17 4!!- 61.84 78.74 8f 198.7 252.9 l 1 1 8 9.388 11.95 *i 63.46 80.81 8| 204.4 260 3 1 16 10.02 12.76 *16 65.10 82.89 8| 210.3 267.9 2 10.68 13.60 5 66.76 85.00 9 216.3 275.4 2ft 11.36 14.46 K.L. "1 6 68.44 87.14 91 222.4 283 2 21 12.06 15.35 H 70.14 89.30 n 228.5 290.9 2ft 12.78 16.27 "16 71.86 91.49 n 234.7 298.9 2i 13.52 17.22 H 73.60 93.72 91 241.0 306.8 2 ft 14.28 18.19 5ft 75.37 95.96 H 247.4 315.0 2f 15.07 19.18 6| 77.15 98.23 9f 253.9 323.2 2ft 15.86 20.20 5ft 78.95 100.5 91 260.4 331.6 2i 16.69 21.25 5i • 80.77 102.8 10 267.0 340.0 2ft 17.53 22.33 "16 82.62 105.2 101 280.6 357 2 a* 18.40 23.43 5| 84.49 107.6 101 294.4 374.9 2n 19.29 24.56 5H 86.38 110.0 10| 308 6 392.9 2| 20.20 25.00 6f 88.29 112.4 11 323.1 411.4 211 21.12 26.90 J 1 6 90.22 114 9 111 337.9 430.3 8i 22.07 28.10 5£ 92.17 117.4 Hi 353.1 449 6 2H 23.04 29.34 51f 94.14 119.9 ii| 368.6 489.4 These figures represent the theoretical weights of steel. Iron will run about 2 per cent lighter. THE SCHOOL HOUSE. 97 TABLE 21. Standard Gauges. U.S. STANDARD GAUGE. BIRMINGHAM GAUGE. No. of Gauge Thickness in Inches. Weight Square Foot. No. oi Gauge Thick- ness in Inches Weight Sq. Foot. • fractions Decimals. Iron. Steel. Iron. 1 Steel. 7-0's 6-0's 1 2 15. 32 .5 •46875 20.00 18.75 20.4 19.125 — - 5-0's 0000 000 00 1 2 3 4 5 6 7 8 9 10 11 1 6 JLi 3 2 a .4375 .40625 .375 .34375 .3125 .28125 .265625 .25 .234375 17.50 16.25 17.85 16.575 0000 .454 18.22 18.46 8 11 3 2 -5. 16 A i 4 15. 64 7 15. 13.75 12.50 11.25 10.625 10. 9.375 15.30 14.025 12.75 11.475 10.8375 10.2 9.5625 000 00 1 2 3 4 .425 .38 .34 .3 .284 .259 .238 17.05 L6.25 13.64 12.04 11.40 10.39 9.55 17.28 15.45 13.82 12.20 11.55 10.53 9.68 32 li 64 -3_ 1 6 ■ ^ 1_ .21875 .203125 .1875 8.75 8.125 7.5 8.925 8.2875 7.65 5 6 7 .22 .203 .18 8.83 8.15 7.22 8 95 8.25 7.32 64 -5. 32 .a. 64 .171875 6.875, 7.0125 8 .165 6.62 6.71 .15625 .140625 6.25 5.625 6.375 5.7375 9 10 .148 .134 5.94 5.38 6.02 5.45 8 -I- 64 * .125 5. 5.1 11 .12 4.82 4.88 12 .109375 4.375 4.625 12 .109 4.37 4.43 13 .09375 3.75 3.825 13 .095 3.81 3.86 14 5 . 64 .078125 3.125 3.1875 14 .083 3.33 3.37 15 T2"8 .0703125 2.8125 2.86875 15 .072 2.89 2.93 16 _1- 1 6 .0625 2.5 2.55 16 .065 2.61 2.64 17 9 160 .05625 2.25 2.295 17 .058 2.33 2.36 18 -1- 20 .05 2. 2.04 18 .049 1.97 1.99 19 T60 .04375 1.75 1.785 19 .042 1.69 1.71 20 -3. 80 .0375 1.50 1.53 20 035 1.40 1.42 21 _ll- 320 .034375 1.375 1.4025 21 .032 1.28 1.30 22 32 .03125 1.25 1.275 22 028 1.12 1.14 23 _8_ 320 .028125 1.125 1.1475 23 .025 1.00 1.02 24 4_0 .025 1. 1.02 24 .022 .883 .895 25 3^0 .021875 .865 .8925 25 .02 .803 .813 26 _3_ 160 .01875 .75 .765 26 .018 .722 .732 27 -11_ 640 .0171875 .6875 .70125 27 .016 .642 .651 28 -1. 64 .015625 .625 .6375 28 .014 .562 .569 29 . 9 . 640 .0140625 .5625 .57375 29 .013 30 _1- 80 .0125 .5 .51 30 .012 31 64 .010985 .4375 44625 31 .01 32 _13_ 1280 .01045625 .40625 .414375 32 .009 33 _3_ 320 .009375 ' .375 .3825 33 .008 34 _L1_ 1 280 .008593:5 .34375 .350625 34 .007 35 _5_ 640 .0078125 .3125 .31875 35 .005 36 a_ 12 80 .00703125 .28125 .286875 36 .004 37 _17_ 2560 .00664062 .265625 .2709375 37 38 160 .00625 .25 .255 — — — — All sheets of iron and steel are rolled to U.S. standard gauge unless otherwise ordered- The low temperature (as compared with iron) at which steel plates have to be finished, causes a slight springing of the rolls, leaving the plate thicker in the center than on the edge. This is especially noticeable in plates less than ft i nc h thick and over 66 inches wide, which* may be of full thickness on the edge and yet be as much as ]/ % inch thicker in the middle. 198 THE SCHOOL HOUSE. TABLE 22 Estimated Weights of Galvanized Sheets. U.S. Stan- dard Gauge 10 12 14 16 18 20 22 24 25 26 27 28 29 30 Weight per / sq.ft., lbs ( 5.781 4.531 3.281 2.656 2.156 1.656 1406 1.156 1.031 .9062 .8437 .7812 .7187 .6562 Weight per / sq. ft., oz. ( 92.5 72.5 52.5 42.5 34.5 26.5 22.5 18.5 16.5 14.5 13.5 12.5 11.5 10.5 Size of Sheet We IGHT of Sheet— -Pounds 24 x 72 69 54 39 32 26 20 17 14 12 11 10 9 9 8 24 x 84 81 63 46 37 30 23 20 16 14 13 12 11 10 9 24 x 96 93 73 53 43 35 27 23 19 17 15 14 13 12 11 24 x 120 116 91 66 53 43 33 28 23 21 18 17 16 14 13 26 x 72 75 59 43 35 28 22 18 15 13 12 11 10 9 9 26 x 84 88 69 50 40 33 25 21 18 16 14 13 12 11 10 26 x 96 100 79 57 46 37 29 24 20 18 16 15 14 12 11 26 x 120 125 98 71 58 47 36 30 25 22 20 18 17 16 14 28 x 72 81 63 46 37 30 23 20 16 14 13 12 11 10 9 28 x 84 94 74 54 43 35 27 23 19 17 15 14 13 12 11 28 x 96 108 85 61 50 40 31 26 22 19 17 16 15 13 12 28 x 120 135 106 77 62 50 39 33 27 24 21 20 18 17 15 30 x 72 87 68 49 40 32 25 21 17 15 14 13 12 11 10 30 x 84 101 79 57 46 38 29 25 20 18 16 15 14 13 11 30 x 96 116 91 66 53 43 33 28 23 21 18 17 16 14 13 30 x 120 145 104 113 82 82 59 66 48 54 39 41 30 35 29 26 23 21 20 18 16 36 x 72 25 21 19 16 15 14 13 12 36 x 84 121 95 69 55 45 35 30 24 22 19 18 16 15 14 36 x 96 139 109 79 64 52 40 34 28 25 22 20 19. 17 16 36 x 120 173 136 98 80 65 50 42 35 31 27 25 23 22 20 42 x 72 121 95 71 56 45 34 29 24 22 19 18 16 15 14 42 x 84 142 162 111 127 80 92 65 74 53 41 34 39 28 32 25 29 22 25 21 24 19 22 18 20 16 42 x 96 60 46 18 42 x 120 202 L59 115 93 75 52 58 40 49 34 41 28 36 25 33 22 29 20 27 19 25 17 23 48 x 72 139 109 79 64 16 48 x 84 162 125 92 74 60 46 39 32 29 25 24 22 20 18 48 x 96 185 145 105 85 69 55 45 37 33 29 27 25 23 21 48 x 120 231 181 131 106 86 66 56 46 41 36 34 31 29 THE SCHOOL HOUSE. 199 TABLE 23. Circumferences of Circles. Comprehending Diameters Used by Boiler Makers. Diameter in Circumference Area in Diameter in Circumference Inches. in Inches. Sq. Inches. Inches. in Inches Sq. Inches 12 . 37f 113 58 1824 2642 14 44 154 60 188! 2827! 16 504 201 62 194| 3019 18 56* 254! 64 201 3217 20 62$ 3144 66 207} 213| 3421! 22 69 3804 68 3631| 24 75f 452f 70 2195 3848! 26 81| 531 72 2264 4071! 28 875 615| 74 232g 43005 30 94j 7065 76 238 & 4536! 32 1004 804| 78 2445 44788 34 1063 908 80 251! 5026! 36 113 10175 82 257! 5281 38 1191 11344 84 263J 5541 1 40 125| 1256| 86 2704 58085 42 1311 ' 1385! 88 276! 60824 44 1384 1520! 90 282| 6361f 46 H4| 1662 92 289 6647| 48 150f 1809! 94 295! 6939f 50 157 1963! 96 301! 7238! 52 163i 2123$ 98 3075 7543 54 169| 2290| 100 314! 7854 56 175J 2463 102 320| 8171| Boilermakers usually add three times the thickness of the plate to length of iron for the take-up in rolling; also add for laps, single or double riveting. TABLE 24. Number of Tubes Usually Put in Return Tubular Boilers. Hand-holes Under Tubes. Manhole U NDER Tu BES. Diam. 2A-Inch Tubes. 3-Inch 3J-Inch Tubes. 4-Inch Diar 3-Inch 3J-Inch Tubes. 4-Inch Boiler. Tubes. Tubes. Tubes. Tubes. 36 38 26 _ _ _ _ _ 42 52 38 - - 42 - 22 18 44 _ 38 34 22 44 28 26 20 48 _ 52 38 34 48 44 28 26 54 _ 54 44 34 54 56 44 36 60 _ 82 64 54 60 62 54 44 66 _ _ 72 54 66 - 88 66 54 72 _ _ 92 72 72 124 86 70 - - - - - 78 132 100 84 200 THE SCHOOL HOUSE. TABLE 25. Dimensions of Standard Wrought Iron Pipe. Inches. Actual Diameter. Circumference. Inches. Length pf Pipe in feet per Square Foot of Surface. Area. Square Inches. Nominal Inside Diam. Inside. Outside. H Internal. External. Inside. Outside. Internal. External. i .27 .40 .07 .84 1.27 14.15 9.44 .06 .12 ± .36 .54 .08 1.14 1.69 10.50 7.07 .10 .22 8 .49 .67 .09 1.55 2.12 7.67 5.65 .19 .35 2 .62 .84 .10 1.95 2.65 6.13 4.50 .30 .55 3 4 .82 1.05 .11 2.58 3.29 4.63 3.63 .53 .86 1 1.04 1.31 .13 3.29 4.13 3.67 2.90 .86 1.35 H 1.38 1.66 .14 4.33 5.21 2.76 2.30 1.49 2.16 H 1.61 1.90 .14 5.06 5.96 ■ 2.37 2.01 2.03 3.83 2 2.06 2.37 .15 6.49 7.46 1.84 1.61 3.35 4.43 2Jr 2.46 2.87 .20 7.75 9.03 1.54 1.32 4.78 6.49 3 3.06 3.50 .21 9.63 10.96 1.24 1.09 7.38 9.62 31 3.56 4.00 .22 11.14 12.56 1.07 .95 9.83 12.50 4 4.02 4.50 .23 12.64 14.13 .94 .84 12.73 15.90 4 1 4.50 5.00 .24 14.15 15.70 .84 .76 15.93 19.63 5 5.04 5.56 .25 15.84 17.47 .75 .62 19.99 24.30 6 6.06 6.62 .28 19.05 20.81 .63 .57 28.88 34.47 7 7.02 7.62 .30 22.06 23.95 .54 .50 38.53 45.66 8 7.98 8.62 .32 25.07 27.09 .47 .44 50.03 58.42 9 9.00 9.6$ .34 28.27 30.43 .42 .40 63.63 73.71 10 10.01 10.75 .36 31.47 33.77 .38 .35 78.83 90.79 11 11.00 11.75 .37 34.55 36.91 .34 .32 95.03 108.43 12 12.00 12.75 .37 37.70 40.05 .32 .30 113.09 127.67 13 13.25 14.00 .37 41.62 43.98 .29 .27 137.88 153.94 14 14.25 15.00 .37 44.76 47.12 .27 .25 159.48 167.71 15 15.40 16.00 .28 48,48 50.26 .25 .24 187.04 201.06 TABLE 26. Expansion of Metals. The linear .Expansion, or Extension of Metals for One Degree Rise in Temperature. Material. Increase of Length in One Foot for an Increase in Temperature of 1° F. Material. Increase of Length in One Foot for an Increase in Temperature of 1° F. Cast-Iron Wrought-Iron Steel Tubes Copper .0000740 .0000823 .0000719 .0001146 Brass Zinc Lead Tin .0001244 .0001961 .0001900 .0001692 To find the amount of expansion or contraction of a bar or pipe of given length, which will be caused by a given change in tempera- ture, multiply the length in feet by the number of degrees of change in temperature. Multiply this product by the co-efficient given in THE SCHOOL HOUSE. 2 01 the table for the material employed. The result will be the ch in length in inches. Iron pipes which are used in steam and hot-water fitting expand about one and one-half inches for 100 feet in length. In long lines of pipe this expansion must be provided for; other- wise it will make trouble h\ breaking connections or shoving appa- ratus out of place. TABLE 27. For Estimating Size of Coal-Bin. Cubic Feet in One Ton. Kind of Coal. Short Ton, 2,000 lbs. Long Ton, 2,240 lbs. Broken Egg Stove Nut Pocahontas 33. 33.6 34.2 35. 36. 37. :;7.(; 38 2 39.2 40.2 The folio-wing is from tests by Mr. D. P. Sullivan, Sealer of Weights and Measures, Boston, Mass. Kind of Coal. One Ton. Cubic Feet. Cubic Inches White Ash Stove 37 116 White Ash (egg) Stove 36 36 Shamokin Stove 37 662 Lackawanna (nut) Stove 31 857 Franklin ( Ljkens Valley) Stove 38 164 Lehigh (hard egg) Furnace 33 576 Lehigh (free burning) Furnace 36 62 Lackawanna (free burning) Furnace 38 796 New River Soft Steam 36 1295 Cumberland Blacksmiths' 30 723 INDEX PAGES Air, amount heated 75, 98 amount for respiration . . 24, 27 amount for ventilation . . 28,41 carbonic acid in 24-29 carbonic oxide in 25 circulation of . . . .35, 44-52, 54, 57, 58, 59, 65 composition of 24, 25 humidity of 28, 29 impurities in 24-27 leakage in school-rooms 51, 54, 55, 61 lime water test for carbonic acid in 29-32 measurement of ... . 33, 35—39 nitrogenous poison in. . . 25, 26 supply for school-rooms- . 50, 60, 61, 62 temperature of ... 38, 39, 48, 49, 60, 61, 62, 75 valves in radiators .... 96 velocity at inlets . .36,37,51,52 vitiated by lights 29, 53 volume and weight . . . . 39, 48 Anemometers 33-37 Appropriation for building . . 6 Architects competition plans by . 2,6 Architects to file plans with inspector 3 Automatic heat control . . 98, 99, 100 Basements 11, 12 Bicycle runs 12 Blackboards 22 Boiler, care and management of 115-117 cast iron 76, 86, 87 coal burned by ... . 74, 75, 78 construction of 75-80 covering 185 fittings required for . . . 87, 92 and furnace rooms . . . . 11, 12 grates for 75, 76, 78 heating surface of . . . 76, 77, 78 horse-power of . 74, 81, 82. 83, 89 horizontal tubular . 76, 77, 81, 82 inspection of 90-92 Massachusetts laws relating to 91, 92 Massachusetts inspectors' rule for pressure .... 85 U.S. standard for pressure 85 plans of settings for . 186-189 safety valves for 80, 87, 91, 92 settings for ... 83-85, 186-189 Boiler, size of 81, 82 smoke flues for 76-79 tubes for 76, 79 upright tubular 76, 86 water tube 86 Building Committee, appoint- ment of 2, 6 Building, construction of . . . S, 9 Care of heating apparatus . . 108-119 Casings for furnaces .... 103, 137 for radiators 96, 97 Cast iron furnaces 102 Cast iron sectional boilers . . 86, 87 Cast iron registers 64, 195 Chemical laboratories .... 12 Chimneys . . . . 57, 58, 66-69, 71-73 Circulation of air 35, 44, 46-54, 57-59,65 Clocks 22 Clothing-rooms 12, 13 Coal, amount burned . . . 74, 75, 78 Cold-air rooms . . . 12,'105, 109, 110 Combination of furnace and fan . . . 105, 106 144, 146, 147, 148 Combination of furnace and steam heat 105, 144, 146, 147, 148, 152, 153 Corridors 12, 13 Cost of fuel 62 of ventilation . . .42, 44, 62, 75 Dampers . 53, 54, 64, 65, 68, 111, 118 Deflectors and diffusers .... 53 Desks 19, 20, 21 Ducts and flues, foul air . . . 52, 54-58, 61, 62, 66-70 Ducts and flues, warm air 51, 52, 63-65 Engineers and firemen, licensed 88-90 Erroneous ideas of ventilation . 42-44 Exits 14, 15 Fans 50. 56, 69 105, 106 Fire, means for preventing spread of 3, 9, 10, 11 Fire escapes on school houses . 15 Figures, 1-9, school house . . furniture 19, 20, 21 10, Professor Wolpert's Air Tester 30 11, Lime Water Apparatus 32 12, Template for correcting anemometer 34 13 and 14, Form of air inlet 35 15. 16. 17 and 18, measuring air with anemometer . . 36, 37 19, 20, 21. location of inlets and outlets and circulation of air in school-rooms . 47, 48 INDEX. 203 V j T-. PAGES t iremen and Engineers, licensed 88-90 Flap valves 54 55, 58 Foot warmers 13, 184,'l85 Furnaces, cast-iron 102 and fan, combination of 105, 106 grates for J01 and hot water, combination . of 105, 106 location of . . . 101, 103, 104, 111 management of 117-119 Pipes for 1 05 P lt for 103 regulating temperature of 103, 104 setting of 103 size of 10i smoke pipes 103, 104 and steam-heat combination of 105 test for gas leakage .... 102 twin connected 105 wrought iron 102 use of, in school buildings 101 Galvanized iron, dampers ... 54 iron, size and weight of sheets 198 iron vent-flues 58 Gas engines 106 lights 53 Glass 13, 16 Grates, boiler 7.-,, 76, 78 furnace 101 Heat, automatic control of . . 98-100 in vent flues .... 66-70, 106, 107, 111, 112 Heating apparatus, location of . 53, 54 cost of 02 Height of school buildings . . 7, 8 Inlets, air. form of 35 air, location of . 44, 46-49, 58, 64 air, size of . . . 51, 60, 61, 63, 64 Janitors, duties of and instruc- tions for 108-1 19 Leakage of air 51,55,56 Lime water test for purity of air 29-31 apparatus for preparing . . 31-33 Location of air-inlets and outlets 35. 44, 46-49, 58, 60, 61. 63, 64, 65, 68, 70 of heating apparatus 53, 104, 105 of school buildings . . 1, 6, 7 Massachusetts laws for construc- tion of buildings . . . 2, 3, 4, 5 laws for inspection of steam- boilers 90, 91, 92 laws for licensing engineers and firemen .... 88, 89, 90 requirements to prevent spread of fire .... 9, 10, 11 requirements for ventilation 5, 41, 42 m , . PACES Measurement of air ... 33, 35_38 Mixing dampers and valves . . ra • ; 68, 64, 104, 106 Flans for and descriptions of schoolhouses, Part II. 127 Plates. I, one-room schoolhouse 128-130 II and III, one-room portable schoolhouse 130-133 IV, V and VI, two-room, one-story schoolhouse, 133-139 VII, VIII and IX. two-room two-story schoolhouse. 139-144 X, XI. XII, XIII and XIV, four-room, two-story schoolhouse I44_i4g XV, XVI and XVII, five- room, two-story school- house 148-154 XVIII, XIX and XX, six- room, two-story school- house 153-156 XXI, XXII, XXIII, XXIV, seven-room, two-story schoolhouse 156-162 XXV, XXVI, XXVII and XXVIII, eight-room, two- story schoolhouse . . . 162-166 XXIX. XXX, XXXI, and XXXII, eight-room, two- story schoolhouse . . . 166-171 XXXIII, XXXIVandXXXV small high or a grammar schoolhouse 171-179 XXXVI and XXXVII sani- tary buildings .... 180, 181 XXXVIII, direct-indirect radiator 179-182 XXXIX. portable furnace for small hall or church 183, 184 XL, foot-warmer for school- house corridor .... 184, 185 XLI, XLII and XLIII. set- ting for one horizontal tubular boiler .... 186-188 XLIV, section of setting for two horizontal tubular boilers 189 Plans, competition 2, 1; to be filed with inspector. . 3 Plenum and exhaust systems .... 50, 51, 55 Prevention of spread of fire . . 3, 9, 10, 11 Radiation, direct 97, 98 direct-indirect 97 indirect 95-97, 99, 100 Radiators, casing 95-'.'7 cast-iron . 70, 95, 96 piping 70, 93 Rooms 17, 18, 23 204 INDEX. PAGES Sanitary buildings and fixtures, care of 120-126 Seats 18, 19, 20, 21 Stairs 12, 14, 15 Stack-heaters . 68, 69, 106, 107, 119 Steam-pipes 69, 70, 93-95 Steam-valves 94, 96 Systems, defective 42-46 exhaust and plenum . 50, 51, 55 Tables 1, for Wolpert's air test . . 31 2, of wind velocity and pressure 40 3, of tests of amount of heat and air in school- houses 60 4, of tests of amount of heat and air in school- houses 60 5, of tests of amount of heat and air in school- houses 61 6, of tests of amount of heat and air in school- houses 61 7, relative cost of fuel in schoolhouses 62 8, of boiler, grate and heating surfaces 76 9, of area of grate surface and tube opening .... 76 10, of standard boiler tubes . 77 11, standard sizes of boilers 81, 82 12, of dimensions of brick settings boilers 84 13, of dimensions of brick settings boilers 85 14, of sizes of supply and return steam-pipes .... 93 15, of areas of rectangular openings 190, 191 16, of areas and circumfer- ence of circles 192 PAGES Tables: 17, for equalizing diameter of pipes 193 18, of number of gallons in round tanks and cisterns . 194 19, of capacity of pipes and registers 195 20, of weight of steel bars per foot 196 21, of standard gauges . . . 197 22, of weights of galvanized sheets 198 23, of circumferences of circles used by boiler makers . 199 24, of number of tubes used in return tubular boilers . 199 25, of dimensions of stand- ard wrought-iron pipe . . 200 26, of expansion of metals . . 200 27, for estimating size of coal bins 201 Temperature in school-rooms 41, 60, 61, 62, 118 Thermometers 22 Try-cocks in water-pipes ... 11 Ventilation, Massachusetts re- quirements for 41, 42 erroneous ideas of . . 42, 43, 44 systems of 45, 46 Vent-ducts, flues and shafts . . .... 54, 56, 57, 66-70, 106, 107 Vestibules 14 Warm-air ducts and flues . . . 63-65 Water-motors 106 Wind, action on chimneys and vent-flues 63-65 varying conditions of . . . 56, 70 velocity and pressure . 39, 40, 56 Windows 13, 16, 17 Wire grills . . . . 64, 65 Wolpert's air test . .... 29,30,31 Wooden flues and ducts, not allowed 3 NOV 25 1905