37-2 



THE GARDENER. 



[Aug- 



CANNELL'S PATENT ECONOMISING BOILER. 



The long sharp weather of last winter, and the immense consumption of fuel to 

 keep up the necessary temperature to preserve my plants, caused me to ponder 

 much about heating our horticultural buildings, and at the same time to see if it 

 was not possible to utilise the great amount of heat which has been, up to the 

 present time, allowed to escape up the chimney. I determined to put my 

 ideas together, and see if I could not combine all the qualities that a boiler 

 should possess, and the annexed engravings and the following particulars will 

 show how I have succeeded. 



The larger engraving and boiler (fig. 18) consists of nine or more separate hollow 

 castings, placed one upon another. Upon brickwork is placed the basement or 

 No. 1 casting, consisting of a hollow rectangular frame, into which are fixed 



Fig. 18. 



eight (more or less, according to the size of boiler) circular hollow fire-bars, 

 placed at such a distance from one another as to allow sufficient space for the 

 draught. 



At the back or further end of this casting are the return-pipes, and in the 

 front the discharge-pipe for cleansing the interior of the boiler at any time. The 

 ashpit is formed by the brickwork supporting the first or basement casting, and 

 is enclosed by a door hung on a solid cast-iron frame, built into the brickwork 

 or otherwise. The furnace-door is to be hung in the same way. 



Upon the first casting are placed four other separate hollow castings, of which 

 Nos. 2 and 3, forming the sides of the furnace, are fluted and placed parallel with 

 the hollow fire-bars, and are of such a length that the two remaining castings, 



