THE MAGAZINE 



OF 



HORTICULTURE, 



NOVEMBER, 1850. 



ORIGINAL COMMUNICATIONS. 



Art. I. Polmaise Method of Heating Greenhouses and 

 Hothouses, compared with Hotwater, scientifically and 

 practically considered. By R. B. Leuchars. 



{Continued, from p. 441.) 



Havimg considered the merits of hot air and hot water, in 

 comparison with each other, I shall now point out some of 

 the causes of faihire in hotwater apparatuses, which have led 

 to the premature condemnation of this method, with the 

 view of showing that these failures are not attributable to 

 the system, nor the principles upon which it works, but to 

 a misconstruction of the one, and a misapplication of the 

 other. 



I may here remark, that many apparatuses that have come 

 under my observation have failed through the most trifling 

 causes, so trifling, indeed, that the necessary alterations 

 would cost only a few dollars to convert the useless and 

 unprofitable into a perfect and efiicient apparatus; and I 

 liave seen some instances of these unworkable apparatuses 

 removed and destroyed, and the whole cost sacrificed, when 

 the opinion of a person who understood the subject would 

 have saved the apparatus from destruction, and made it 

 answer the intended purpose. 



Perhaps the most frequent defect in a hotwater apparatus, is 

 " imperfect circulation." It is this circulation which prevents 

 the water in the boiler from being heated above the boiling 



VOL. XVI. NO. XI. 61 



