Greenhouses and Hothouses. 255 



others, I shall be glad to be informed of it. My own ex- 

 perience has convinced me, that you can obtain little more 

 than half the calorific influence of the fire, and that half at 

 a temperature and in a condition which ought never to be 

 admitted into a hothouse. 



Notwithstanding the overwhelming amount of evidence 

 which has been adduced against hot air for heating hot- 

 houses, there are many who do not hesitate to recommend it. 

 But we hope the day of dictatorial and vituperative contro- 

 versy on disputable subjects is gone past. We are not to 

 risk our reputation, or be misled by the vague assertions 

 of theoretical enthusiasts, who seem to be insensible of their 

 liability to err, and establish their notions of right and 

 wrong upon the assumptions of their own infallibility. The 

 learned editor of the Gardenei'^ s Chrotiicle, who is the chief 

 horticultural theorist of England, and who is only groping 

 in the dawn of a profession of which he wishes to be con- 

 sidered as a master and practical teacher, has been the strong- 

 est advocate of this system of heating, showing, in a most 

 striking manner, how comparatively little the greatest ca- 

 pacities can perform beyond the limits of their own province. 



Clifton Park, Baltimore^ April, 1850. 



We commend the above paper to the careful perusal of 

 all who are about erecting greenhouses, hothouses, or vineries. 

 Mr. Leuchars has shown, that he fully understands the sub- 

 ject he has taken hold of, — a subject, we do not hesitate to 

 say, that receives but little reflection, and is but little under- 

 stood. All advocates of Polmaise should especially note his 

 views on the principles of heating. Mr. Leuchars has done 

 a good service in exposing so fully the absurdities of the 

 Polmaise system of heating", — a system which we believe 

 can never be adopted in this country, only at the sacrifice of 

 great labor and expense. We have read all that its greatest 

 advocates have advanced in its favor, and once attempted to 

 warm a small house in this manner : and though we were 

 enabled to keep out the frost, it was only at a waste of fuel 

 and labor. — Ed. 



