VARIOUS METHODS OF HEATING DESCRIBED IN DETAIL. 217 



its position, but the chief object was to hold and retain a sup- 

 ply of warm water, which it did admirably, and effectually 

 warmed the house besides. The manner in which this tank 

 retained the heat after the fire had ceased to burn, impressed 

 me with the idea that heat could be drawn off from the regular 

 apparatus, and applied afterwards when necessary, or for any 

 other purpose. I believe the heat generated by wooden tanks to 

 be most favorable to the structural development of plants, as con- 

 taining more moisture than heat radiated from either iron or 

 brick, because the temperature is lower. 



We have already remarked that the tank system of heating 

 hot-houses has but very lately been brought into general notice, 

 and still receives much less attention than its utility, simplicity, 

 and economy claim for it ; and where it has been used, it is 

 chiefly as a medium of bottom-heat, for which it is undoubtedly 

 superior to anything that has yet been applied. The efficiency 

 of tanks in supplying atmospheric heat has been doubted by 

 some and denied by others, without, however, as far as I can 

 learn, bringing any practical facts to bear upon the subject. I 

 am convinced that the system, rightly applied, will prove the 

 doubts to be entirely without foundation. Simplicity in any 

 system of heating is a point of incalculable importance ; and 

 when economy and adaptibility are combined with it, a claim is 

 presented which facts only can overthrow. It is very true that 

 we practicals are, many of us at least, prone to adhere bigotedly 

 to any method with which we are acquainted, and which we 

 have already proved safe and simple, and are unwilling to 

 believe that any other method can be safer and simpler than 

 itself. Gardeners are proverbially a cautious and thoughtful 

 class of men; perhaps seldom directly opposing principles 

 founded upon theoretical deductions, but frequently slow in 

 instituting experiments with the view of establishing their truth. 

 In these days of invention and progress, it is the duty of every 

 one engaged in horticultural pursuits, and particularly garden- 

 ers, not only to make themselves acquainted with the views and 

 opinions of other persons, but to test, by various counter-experi- 

 ments, the conclusions they have drawn. No man is justified 



