THE CONSTRUCTION OF PLANT HOUSES. 79 



ally influences plants profoundly, and usually beneficially, it is yet 

 undetermined just how this effect is brought about. It is highly 

 probable, however, as Lemstrom himself suggests, that the modifi- 

 cations are not the direct result of electrification of the plants or 

 the atmosphere, but rather follow some chemical change in the 

 atmosphere which is engendered by the current. The experimenter 

 is to continue his studies, and I expect to supplement them in 

 America, for I consider it the most promising field in the many 

 obscure interrelations of electric energy and horticultural practice. 

 I expect little practical result to follow auy method of direct 

 electrification of vegetation, but there is promise in those broader 

 applications which intensify the normal processes of Nature. 



The announcement for the next Saturday was a paper on "The 

 Construction of Plant Houses," by W. A. Burnham, Irvington-ou- 

 Hudsou, N. Y. 



MEETING FOR DISCUSSION. 



Saturday, February 10, 1894. 



A Meeting for Discussion was holdeu today at eleven o'clock, 

 the President, Nathaniel T. Kidder, in the chair. The follow- 

 ing paper was read by the author. 



The Construction op Plant Houses. 



By W. A. BUKNHAM, Irvington-on-Hiuison, N. Y. 



I have been requested to give a paper on Greenhouse Construc- 

 tion, and so far as practicable to illustrate by diagrams and plans 

 the most approved construction. In accepting the invitation of 

 your Committee I cannot hope to cover the whole field of invention 

 and the plans which have been presented to the public as the 

 ne plus ultra of greenhouse building, but will present only such 

 modes and details of construction as have come under my personal 

 observation during the past twenty-one years of my experience as 

 a builder, and by their use have proved their adaptation to the 

 requirements of a greenhouse. 



The progress of greenhouse building during this time has been 

 very marked, as also it had been during the previous ten years, sa 



