DESCRIPTION OF A STOVE, 27 



through them freely, without fo much air entering with it as 

 would condenfe it, or fink the temperature below the degree 

 neceflary for combuftion. 



V V are the external parts of the two heat openings. H eat openings. 



m m Apertures of the flove, by which the air, that is to 

 iflue through the heat openings, enters. Thefe are clofed 

 when the air is drawn from without through a pipe paffing 

 under the floor ; which is much more advantageous for renew- 

 ing the refpirable air of the apartment, and prevents the dan- 

 ger of currents of cold air attracted by the fire; and which 

 is necefTary, as I have obferved, whenever the volume of air 

 in the apartment is not fufficient, to fupply both the confump- 

 tion of the fire, and the circulation in the heat pipes. 



Fig. 2. is a plan of the foundation of the hearth at the 

 height of the line A B, fig. 1 . II are empty fpaces, to receive 

 the air, and convey it into the compartments, where it is to 

 be heated before it iflues by the heat openings, whether the 

 air be obtained from without, or fimply by the apertures m m, 

 fig. I. 



Fig. 3. pi. IV. plan at the height of the line C D, fig. I; that 

 above the door of the fire-place, nnnn are the double plates 

 of caft iron, forming the compartments in which the air is to 

 receive the effect of the heat of the fire, 



o o The empty fpace between thefe plates. f 



Fig. 4. Front feclion at the line I K, fig. 3. The arrows 

 indicate the direction of the fmoke in the circulatory pipes of 

 the front part.* 



In this the plates of iron n n are feen in their perpendicular 

 fituation, with the tongues which form their compartments on 

 each fide of the fire-place. One of thefe plates is reprefented 

 in front fig. 7. 



T is an opening left at the bottom of the fourth circulatory 

 pipe, to reftore the draught of air in the fire-place, if necef- 



* Among the number of Swedifli ftoves defcribed and delineated 

 in the collection publifhed by baron Cronftedt there are feveral, the 

 circulating pipes of which pafs under the hearth. This gives them 

 a little more extent no doubt, but as foon as the hearth is covered 

 wjth afhes, the air paffing beneath can receive but a very flight im- 

 preffion of heat; it obliges the fire-place to be railed higher; and it 

 renders the conftruction more complex and expenfive. For thefe 

 reafons I have adopted the moil fjmple plan. 



4 fary, 



