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Lectures on Ventilation

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Lectures on Ventilation
by Lewis W. Leeds
206185Lectures on VentilationLewis W. Leeds


LECTURES ON VENTILATION:


BEING A COURSE DELIVERED IN THE


FRANKLIN INSTITUTE,

OF PHILADELPHIA,


DURING THE WINTER OF 1866-67


BY LEWIS W. LEEDS,

Special Agent of the Quartermaster-General, for the Ventilation of Government Hospitals during the War; and Consulting Engineer of Ventilation and Heating for the U. S. Treasury Department.



Man's own breath is his greatest enemy.



NEW YORK:
JOHN WILEY & SON, PUBLISHERS,
2 CLINTON HALL, ASTOE PLACE.
1869.



Entered according to Act of Congress, in the year 1868, by
LEWIS W. LEEDS,
In the Clerk's Office of the District Court of the United States for the Southern District of New York.



NEW YORK PRINTING COMPANY,
81, 83, and 85 Centre Street,
NEW YORK.



PREFACE.


These Lectures were not originally written with any view to their publication ; but as they were afterwards requested for publication in the Journal of the Franklin Institute, and there attracted very favorable notice, I believed the rapidly increasing interest in the subject of ventilation would enable the publishers to sell a sufficient number to pay the expense of their publication ; and, if so, that this very spirit of inquiry which would lead to the perusal of even so small a work, might be one step forward towards that much-needed more general education on this important subject.

It was not my desire to give an elaborate treatise on the subject of ventilation. I believed a few general principles, illustrated in a familiar way, would be much more likely to be read ; and, I hoped, would act as seed-grain in commencing the growth of an inquiry which, when once started in the right direction, would soon discover the condition of the air we breathe to be of so much importance that the investigation would be eagerly pursued.

L. W. L.



CONTENTS.



Philadelphia a healthy city—Owing to the superior ventilation of its houses—But the theory of ventilation still imperfectly understood—About forty per cent, of all deaths due to foul air—The death rate for 1865—Expense of unnecessary sickness—In London—In Massachusetts—In New York—In Philadelphia—Consumption the result of breathing impure air—Entirely preventable—Infantile mortality—Report on warming and ventilating the Capitol—Copies of various tables therefrom—Carbonic acid taken as the test, but not infallible—The uniform purity of the external atmosphere—Illustrated by the city of Manchester—Overflowed lands unhealthy—Air of Paris, London and other cities—Carbonic acid in houses—Here we find the curse of foul air—Our own breath is our greatest enemy—Scavengers more healthy than factory operatives—Wonderful cures of consumption by placing the patients in cow stables—City buildings prevent ventilation, consequently are unhealthy—The air from the filthiest street more wholesome than close bed-room air—Unfortunate prejudice against night air—Dr Franklin's opinion of night air—Compared with the instructions of the Board of Health, 1866—Sleeping with open windows—Fire not objectionable—A small room ventilated is better than a large room not ventilated—Illustration—Fresh air at night prevents cholera—Illustrated by New York workhouse—Dr. Hamilton's report—Night air just as healthy as day air—Candle extinguished by the breath—The breath falls instead of rises—Children near the floor killed first—Physicians' certificates do not state "killed by foul air"—Open fire-places are excellent ventilators—All fire-boards should be used for kindling wood—Illustration showing when ceiling ventilation is necessary


The effect produced by heat upon the movements of air—Air a real substance—Exerts a pressure of fifteen tons on an ordinary sized man—It cannot be moved without the expanditure of power—The sun's rays the great moving power—They pass through the forty-five miles of atmosphere without heating it, and heat the solid substances of the earth's surface—Experiments showing the effect of radiant heat and reflected heat—The air of the room not pure and dry—The ordinary moisture absorbs from fifty to seventy times as much as the air—Many gases absorb much more—The moisture in the air the great regulator of heat—Air is heated by coming in immediate contact with hotter substances—Impossibility of any air remaining at rest—The practical application of these principles—The open fire acts like the sun, heating by radiation only—Probable electric or ozonic change in furnace-heated air—The stove heats both by radiation and circulation—The stove nor the open fire not suitable for large crowded rooms—Circulating warmed air best—Erroneous views in regard to ventilation—Experiments with liquids of different densities—When warming and ventilating by circulating air, the escape for the used air should be from the bottom of the room—But when ventilating with cooler air the escape should be from the top of the room—Windows should lower from the top and flues open at the bottom of the room—The fashionable system of heating by direct radiation, without any fresh air, very objectionable


One breath of impure air shortens our life—Difficulty of getting pure air to breathe in houses and cars—Foul air in steam cars—Want of the proper knowledge regarding ventilation among all classes—Want of ventilation in this lecture room—Want of ventilation in the Cooper Institute, and in many other new and splendid buildings—Street cars very foul—My own chamber fully ventilated—I have no new patent idea, sufficient for all time without further thought—Constantly varying conditions require separate intelligent thought and action—The air moves horizontally in summer—Flues are then of no account—We must depend on open doors and windows—How to ventilate a sick room in the morning—The same in the evening—Windows should always lower from the top—To make air move in the summer is the great desideratum—When in motion the cold air falls and warm air rises ; when at rest, it is arranged in horizontal layers, according to temperature—A flue is simply a passage for air of different temperatures—Experiments with flues of different temperatures—Expansion of air by heat—Weight required to keep it from expanding—Heating air weakens it instead of giving it power—Experiments showing draughts by lighted candles—Ventilation of churches—Illustrations not exaggerated—Examination of church in neighborhood—Fresh air taken from foul cellar—No fresh air supplied to churches used as hospitals in Washington—Depending on a sham ventilator painted on the solid wall—Foul air in Philadelphia schools—New York public schools—Many of the ventilators perfect shams—Covered up air-tight by the capping stones—Importance of the evaporation of water—A strong fire in basement will draw gas out of second story stove—A strong fire up stairs will draw foul gases from untrapped sewers—A very healthy location may thus be made very unhealthy—Drs. Palmer, Ford and Earle's report of epidemic at Maple Wood Institute—An arrangement for ventilation that ought to be in every house—Flues generally too small, especially in Philadelphia—Very large ones put in government hospitals, which proved thoroughly efficient—The leading points in regard to heating—The fresh air must be warmed before entering in winter—A hot water furnace requires additional moisture—Heating by steam—Steam-pipes ought to be laid through the street the same as gas and water—Two-thirds of heating surface should be for heating the fresh air and one third for direct radiation—Forty pounds of water required to be evaporated every minute for U. S. Senate Chamber—All stoves should have fresh-air boxes—Dampers in fresh air-boxes not good—Experience has fully demonstrated that careful attention to these things will be amply rewarded by increased health, strength, happiness and longevity


Article relating to the Grand Prize awarded to Hospital Ventilation and other Sanitary arrangements, Paris Exhibition