16 



THE AMATEUE S GBEENHOUSE 



to the circulation of tlie blood in the body— the fuel is the 

 food, the fire is the life, the boiler is the heart, the flow pipe 

 the aorta, and its ramifications the arteries ; the return pipe 

 i« the vena cava and its ramifications the veins. 



In making a selection of a boiler it is of the utmost import- 

 ance to ensure greater power than will be required under 

 ordinary circumstances, and in the case of an extensive range 

 of houses there should be two boilers, and they should be in 

 use alternately during periods of a month or so at a time. In 

 case of an accident to one of them — and the best boilers will at 

 times break down — there is another ready for use, and with' all 





CONICAL BOILEE WITH FEEDIIfG TOP. 



(Thames Bank Iron Company.) 



connections complete, so that the turning of a valve and the 

 lighting of a fire are sufiicieut to save the plants from destruc- 

 tion. We have seen a collection of plants, valued at some 

 thousands of pounds, destroyed through the breaking down of 

 a boiler in a season of intense frost, and at a moment of fes- 

 tivity when no one was prepared for such an emergency. 



The simplest form of boiler for a small house is the IJpright 

 Conical, which consists of a furnace communicating with an 

 upright chimney through the boiler, which is an upright 

 cylinder not necessarily of a " conical" form. This may be 

 used without any brick setting, but is far more serviceable with 

 setting than without it, because of the great power of brick- 

 work to prevent waste of heat. One great advantage of this form 



