Steam and Hot Water for Greenhouse Heating. 189 



appear at all uniform, however, and the observations are not 

 such as to give any satisfactory indications toward an answer to 

 the question. 



EXPERmENTS ELSEWHEEE. 



It appears from the literature readily available, that the use of 

 steam inclosed circuits was invented by Mr. Hague, in England, 

 about 1820,* although certain methods in which 1 he steam passed 

 off at the further end of the house, had been previously in use. 

 At this time the construction of apparatus was such as to require 

 almost constant attention to fires, in order to maintain the tem- 

 perature. Frequent repairs were needed and explosions were 

 common. The first trials with hot water were made by Anthony 

 Bacon and Mr. Atkinson in 1822.§ These men worked independ- 

 ently, and both secured succe.«sful results. 



The laws governing the circulation of liot water are carefully 

 treated by Thomas Tredgold in a paper before the London Horti- 

 cultural Society in 1828.§§ In 1840, John Rogers wrote: "On 

 the whole there appears no doubt that the circulation of hot 

 water in iron pipes is the best means hitherto devised for heating 

 horticultural buildings."** This quotation probably represents 

 about the consensus of opinion on the subject in England to the 

 present day. One of the earlier promoters of this sy*>tem was 

 Charles Hood, author of "A Pmctical Treatise on Warming 

 P>uildings by Hot Water, and an Inquiry into the Laws of Radient 

 and Conducted Heat," 



The use of steam for heating purposes began to receive marked 

 attention in this country some fifteen years ago. In the discus- 

 sions of the Society of American Florists in 1885, the average 

 from estimates in answer to circulars by nearly fifty florists 

 showed that one ton of coal with hot water heated 108 square feet 

 of glass to a temperature of fifty-three and one-third degTees, while 

 with steam the same amount heated 149 square feet to a tem- 

 perature of sixty and three-fourths degrees. The proceedings of 



* Trans. I.on. Hort. Soc. iv. p. 4S4. § Trans. Lon. Hort. Soc, vii. 204. §§ Trans. Lon. 

 Hort. Soc, vii. 568. ** Trans. Lon. Hort. Soc, 3d series, 11. 364. 



