On tlie Comparative Merits of Steam and Hot Water for 



Greenhouse Heating. 



I. EXPERIMENTS AT CORNELL. 



The question of tlie comparative merits of steam and hot water 

 for heating horticultural buildings has received much attentitni 

 from practical men. Experiments have also been made by Pro- 

 fessor Maynard, of Massachusetts, and Professor Taft, of Michi- 

 gan, in comparing the coal consumed and the temperature obtained 

 in houses of similar construction, with all the conditions as nearly 

 alike as possible. The object of the present observations was 

 to learn, if possible, something more concerning the woridngs 

 of the, two systems, which should have a practical beanng on 

 the subject. 



1. Methods; general records. — These experiments were made 

 in the University forcing-houses, a ground plan of which is shown 

 in the diagram, Fig. 1. A, B is a low house twenty by sixty 

 feet, with three-fourths span, the north walk and benches being 

 higher than those on the south side. It is a cool house, used 

 mainly for lettuce and radishes, and is divided into two apart- 

 ments by a board partition. It has a roof pitch of about twenty- 

 two degrees on the south side, and twenty-six and a half degrees 

 on the north side. In the second series, which has the same 

 ground area, house C has a steep roof with a gable eleven feet 

 above the walk. The south slope of this house C is at an angle 

 of some forty degrees, and the north slope about forty-two degrees. 

 The roof of house D has an angle of- nearly thirty-one degrees on 

 the south, and thirty-nine degrees on the north side. A cross- 

 section of this house is shown in Fig. 2, page 177. Both houses 

 have a three-fourths span with lower benches on the south side. 

 C is used principally for tomatoes, D for cucumbers and beans. 

 House E is an ornamental or conservatory attachment, with glass 



