192 ANNUAL REPORT OF THE Off. Doc. 



It is a well known fact that the open blazing fireplace, although an 

 expensive form of heater, is the best for ventilation, happiness and 

 home cheer. The stove furnishes more heat, but is not so good as 

 a ventilator, because with the open fireplace a much larger amount of 

 heat and air are carried up the chimney. It is shown that the un- 

 pleasant heat of stoves may be partly avoided by providing stoves 

 which have a large surface of metal, so that the heat may be dis- 

 tributed evenly over the iron without heating any part to redness, 

 since red-hot iron allows the passage of harmful gases formed in the 

 burning of coal. A disagreeable feature of the stove is the dry air 

 which it furnishes. In all heating, a certain amount of moi&ture 

 must be present to meet the requirements of comfort. An open 

 fire door does not dry the air to any great extent, but the stove should 

 have a receptacle for water. 



Steam radiators are objected to on account of their lack of ventila- 

 tion and their greater expense. 



The warm air furnace brings from outside of the house a constant 

 current of fresh air, carries it over heated surfaces, and discharges 

 it by means of pipes into the different apartments. It is highly rec- 

 ommended for heating purposes, since it serves as a partial ventila- 

 tor, supplies a moist air, and, if adapted to the building in which it is 

 placed, does not allow the escape of gases, smoke or dust into the 

 rooms which it heats. To supply pure, warm air, it is necessary that 

 the fresh air pipe open directly into the fresh out-door air. 



There is a close connection between the methods adapted for 

 heating and those intended for ventilation. Ventilation is defined 

 as the problem of changing the air in a room with sufficient rapidity 

 without at the same time creating draughts. It is generally under- 

 stood that such a change is necessary in an occupied room, because 

 each occupant in every act of respiration is drawing from the air 

 of the room a certain quantity of oxygen and giving out in its stead 

 a quantity of poisonous carbonic acid gas, besides impure exhala- 

 tions from the skin. In a large number of homes no means are used 

 to remove this foul matter, and what was rejected by the body is 

 rebreathed again and again, not only by the person first rejecting 

 it, but by all the inmates of the room. In the blood thus poisoned 

 is laid the foundation of disease. No building materials, and no 

 windows nor doors are absolutely air-tight; if they were so, some 

 modern buildings would be unfit to sustain life, and the history of 

 the ''Black Hole of Calcutta," with its high death rate, might be re- 

 peated in many churches and school houses of the present day. 

 Since pure air is free, and since the rooms of our houses may be sup- 

 plied with it and still be comfortable with a little extra fire, why 

 need we suffer with head-ache, lassitude and disease as a result of 

 its continued lack? 



