312 WARMING AND VENTILATION. 



which, added to the natural veutihition produced by the kitchen tire, 

 will iully suffice to change the air of such a kitchen more than ouce an 

 hour. 



The expense for a whole year for one small gas-burner, consuming 1| 

 feet of gas an hour, and burning six hours a day, would be Sh cubic 

 feet a day, or 3,100 cubic feet a year, which, at the rate of $1.70 a thou- 

 sand feet, would cost $5.27, a very moderate expenditure for getting 

 rid of a nauseous smell, which would otherwise be experienced twice a 

 day. 



It may be added that the preceding results relate to metal pipes 

 placed on the outside and exposed to cooling, while, in general, similar 

 ventilating-pipes may be, and ought to be, made of earthen ware, and 

 placed in the thickness of the walls or in the interior of buildings, 

 which, exposing them less to cooling, would increase the effect ob- 

 tained. In the case of large kitchens with wide fire-places, when the 

 ranges are kept \nery hot, and are used almost all the time, it would be 

 more economical to place a coal-grate in the lower j)art of the chimney, 

 at about the top of the tire-ijlace, and this would also be the most simple 

 and direct method for country-houses. 



107. Use of the lost heat from kitchen-ranges for ventilating and for 

 heating baths. — Besides the advantage of securing a change of air and 

 the removal of bad odors from the kitchen, the hot-water pipes men- 

 tioned in §105 serve to supply baths, which may be established with 

 success, as mentioned in §81 in barracks, as well as in those establish- 

 ments where ])rovisious are cooked for the poor, to be distributed to 

 them gratuitously or sold to them at a low price. The addition of 

 hot-water baths to these useful establishments might thus be made at 

 very little expense. 



An arrangement of this kind is adopted with success in the new lying- 

 in house established by the administration of public assistance, rue du 

 Faubourg St. Jacques, to utilize the lost heat from the stoves used for 

 making plasters. 



108. The baths may be heated also by means of ordinary hot-air 

 kitchen-ranges without recourse to the use of hot-water circulation, or, 

 what is better, by combining the two means of utilizing the heat lost 

 from the range during the time the meals are being prepared. 



109. Privies. — The necessary arrangements to be made in order to 

 prevent the infection which these attachments to buildings often pro- 

 duce vary with the mode of construction adopted and the nature of the 

 building. 



The regulations for the construction of privy-wells are as follows : 

 The down-pipes should dip at their lower end into the contents of the 

 well, or better into a fixed or movable copper basin, into which it is well 

 when it can be done to force water from time to time in order to wash it. 



It follows from these arrangements that the only gases which can 



