328 Economy of Fuel. 



be entirely freed from inconvenience on account of their occasional 

 production, it is only necessary to provide an escape in the manner 

 indicated at F. The kitchen fire place is of course completely closed 

 during the winter. By the adoption of this plan, every flue in the 

 house except one, is rendered useless; and much worse than useless, 

 because, besides occupying a great space, they carry off the hot air 

 which is sent up from the furnace. And yet they do not perform all 

 the purposes of ventilation, since their apertures are below the prop- 

 er level for that object. Seven out of eight have consequently been 

 closed at the top, by boards laid in mortar. 



Ventilation, when required, is readily effected by letting down a 

 sash from the top. 



From November to April, (the time this apparatus is in use,) the 

 average consumption of anthracite is one ton per month ; and no 

 other fuel whatever is required except a little charcoal, and a trifling 

 quantity of light wood for rekindling the fire, should it accidentally 

 become extinct. 



Canvass has been adopted to form the air chamber, because it is 

 lighter, cheaper, more manageable than either iron or brick, and oc- 

 cupies no space of importance, when removed for the summer. 

 Where such removal is not desirable, or where the slightest danger 

 is apprehended, it were probably better to form it of some ordinary 

 building material. The whole of the above apparatus would not 

 perhaps be improperly termed a tent furnace. 



As already stated, the gas pipe in the actual arrangement above 

 described, passes into a kitchen chimney, and the column C, is omit- 

 ted ; consequently considerable loss is sustained notwithstanding the 

 quantity of pipe enclosed in the air chamber. 



In order to assure myself of the practicability of heating an apart- 

 ment on the third floor, by means of the gas thus escaping from the 

 kitchen, as well as to determine the relation of the temperature of 

 the escaping gas, to that of the open air, and to the highest tempera- 

 ture required in the rooms below, experiments were made at the top 

 of the chimney, and at several stages below. Care was taken to 

 allow the thermometer, (which for this purpose was suspended to a 

 measuring line,) time to attain the temperature of the gas at each 

 stage, and then to withdraw it quickly, when about to be examined. 



Exp. 1. In this experiment the air was at 40°; the parlor D, 

 72°; the gas at the very top of the chimney, 134°; and at four feet 

 below, 139°. 



