34 TRANSACTIONS OF THE AMERICAN INSTITUTE. 



and in all conditions, deem it proper that they should notice the 

 more prominent improvements in each which will be deserving of 

 an award. 



The principal novelty in the hot air furnace of Bartlett is its 

 form, and while it is open to the usual objections made against 

 hot air furnaces in allowing the air intended for breathing as 

 well as heating purposes to come in contact with the usually red 

 hot fire box, it is to be commended for the simple manner in 

 ■which the gases of combustion are prevented from finding a way 

 into the hot air chamber. The examiners deem this a cheap and 

 efficient method of heating in situations where a chilling tempera- 

 ture is rapidly produced by immense drafts or currents of cold 

 air, yet they cannot endorse it as the best method of heating. 

 They recommend that a silver medal be presented to the 

 inventor. 



Brown's Water Furnace. 



The object of this invention is to furnish to a house or con- 

 servatory a large quantity of air at a moderate temperature, 

 generally below but never exceeding the boiling point of water. 

 The apparatus is necessarily very large, because the heating sur- 

 face must vary inversely with the temperature, yet the boiler and 

 nearly all the other parts being made of cast iron, it is compara- ' 

 lively cheap. It is well adapted for green houses, for public 

 schools, and for large assembly rooms, where a frequent change of 

 air is more important than high temperature. 



Mr. Brown has an ingenious method of regulating the heat of 

 the water so as not to allow it to reach a state of ebullition. 

 The apparatus requires careful attention, and in the coldest 

 weather the fire should be continuous in order to guard against 

 the danger of freezing. The examiners recommend that a silver 

 medal bo presented to the inventor. 



Baker & Smith's Improved Low Pressure Self-regulating 

 Steam Warming Apparatus. 



The inventors of this apparatus are to be specially commended 

 for the care and caution they have shown in making every part 

 of their arrangement secure against accidents. The boilers they 

 put up are made by other parties, but are tested by the inventors, 

 so as to insure the capability of sustaining about one hundred 

 times the pressure to which they are usually subjected. Tho 

 pipes which distribute the steam and radiate the heat are of the 



