162 Agkicultural Experiment Station, Ithaca, N. Y. 



house, although, it was actually the coldest. Jt is apparent thnt 

 air temperatures are influenced by sun, ventilation, watering and 

 general management, and they- are discontinuous; and they onn 

 not, therefore, be accepted as accurate measures of the liealing 

 capacity of any apparatus. It follows that the perfomiances of 

 two systems can be studied nearly as weU in houses of different 

 construction as in similar ones, for the house is, to a certain extent, 

 eliminated from the problem and the actual work of the a])parati)s 

 is considered. The heat must be measured in and on tlie pipes; 

 after it leaves them it is largely beyond our control. And the 

 dissimilar houses present the actual conditions of commerc;)'!!- 

 establishments better than the others. 



All our experience emphasizes the greater \•alu^? of steam, bnl 

 it must be understood that we do not condemn hot water. Stenni 

 is certainly better for our conditions, and we bciliev-' Ihat iv is 

 superior for verj- large houses where the fall is flight, for most 

 forcing-houses, and for all establishments whion are Hkely w b*- 

 often modified and extended. For conservatory purposes, for 

 straight runs and small houses, it is perhaps equaled — possibly 

 surpassed in some instances — by hot water. Sieam oA'^ercomes 

 obstacles, as elbows and angles and obstnictions, better than hot 

 water. It travels faster and farther. Crooked runs with littlt 

 fall are great diflBculties in hot-water heatiag. Steam can be 

 varied more quickly than hot water. On the other hand, «.teaui 

 is as steady as hot water under proper management, -nd it req.iiivs 

 no more attention. In our own experience, ihe same treat- 

 ment is given both heaters. Plants thrive as well under steam 

 heat as under hot-water heat. The opinion that steam heat is 

 a " dry heat " is erroneous. 



Hot-water heating demands from a third to a hal- more piping 

 than steam heating, and the original cost is, therefore, irreatiT. 

 This additional piping has a certain advantage, however, inas- 

 much as each pipe is less hot than in steam systems and is less 

 lilvely to injure plants which stand close to it. This .advantage is . 

 not great, however, especially in forcing establishiriini1;s where no 



