309 



A FEW OBSEEVATIONS ON HEATING 

 BY HOT WATEE. 



This being a subject that is very intimately connected witL. 

 the cultivation and. forcing of fruits under glass, it has been 

 considered advisable to append a few observations on the 

 principles of heating by hot water ; for, notwithstanding all 

 the elaborate essays that have from time to time appeared in 

 the horticultural press on heating hothouses with hot water — 

 not to say anything of the stirring controversies that have 

 taken place on the subject — I have the best reasons for be- 

 lieving that many whom the matter intimately concerns have 

 stiU. but very vague and erroneous ideas regarding the prin- 

 ciples upon which the proper adjustment of hot-water boUers 

 and pipes depend. And from some cause or other, it is a 

 notion very prevalent that the easiest and shortest way to 

 get deeply immersed in the disagreeable and undefined diffi- 

 culty figuratively termed " hot water," is to plunge into this 

 heating question, in which are involved furnaces, boilers, 

 pipes, fire, and water, besides that unfortunate being who has 

 to control the elements and conditions of combustion so as to 

 have half-a-dozen thermometer-needles in as many hothouses 

 standing at certain hair-like marks at half-a-dozen different 

 times in the four-and-twenty hours. 



It is my belief that, if those who have to do with fixing 

 pipes and boUers were to make themselves acquainted with 

 the effects of heat and the power of gravitation on water, it 



