lOO Heating Green-houses. 



can testify, who have seen the tons of seed, the acres of seed-beds, the 

 many acres of transplanted trees, and the immense stoi-e-cellars where 

 the salable plants are wintered, so as to be ready for shipment at any 

 moment. To realize this, visit Robert Douglass & Son, Waukegan, 

 Illinois. 



HEATING GREEN-HOUSES. 



By W. D. Philbrick, Newton Centre, Mass. 



A USEFUL article, under the above heading, appeared in the January 

 number, from Mr. W. C. Strong. While I do not by any means desire 

 an vuiprofitable controversy with a good friend, still less to set up my 

 opinion against that of an older and much more experienced gardener, 

 there are still some further considerations connected with this subject 

 which deserve notice. 



There is, no doubt, much loss from the hot gas of the coal passing 

 out of the chimney where there is no radiating flue connected with the 

 boiler, or when no boiler is used, from want of length enough in the 

 flue to radiate or conduct all the heat from the coal gases. To over- 

 come this, I have connected with my Hitchings boiler a horizontal flue 

 fifty feet long, in addition to the ordinary direct flue rising perpendicu- 

 larly from the boiler. The gases escaping through the direct flue are 

 quite hot, and this is only used to blow the fire or kindle anew ; but 

 when the horizontal flue is used, the gases escape at a temperature 

 seldom more than twenty degrees higher than that of the house, and I 

 think this difference is needed to secure a good draught. 



In fact, the importance of good draught is so great, that I would not 

 dispense with the direct flue on any account ; and I think the saving of 

 fuel by the use of a long horizontal flue is more apparent than real 

 when the draught is sacrificed. For while we undoubtedly save the 

 heat which would be otherwise carried off" by the burned gases, we are, 

 perhaps, not aware that these very gases are often capable of producing 

 more heat if properly burned in a hot fire with good draught. Coal 

 burned at a dull, cherry-red heat, and especially when in large mass, 

 with imperfect draught, is converted by the combustion into a gas, called 

 carbonic oxide, which passes off" up chimney unburned ; now, if we 

 could burn this gas, we should (theoretically) gain exactly as much 

 more heat as the slowly burned coal yielded in producing it. It is this 

 gas burning which makes the blue flame to be seen over an open fire of 



