ELECTR O- HOR TIC I Z TURE. 



became yellow, browns turned to green, greens lost their 

 brightness, and dark purple became glossy black. When- 

 ever shadows of other leaves protected the foliage the 

 color was unchanged, and the precise limits of the 

 shadow, even to the dentations of the overhanging leaves, 

 were visible for days afterwards. Plants five feet away 

 were little affected at this time, and those 12 feet away 

 were unchanged. 



In all these experiments with ornamental plants, it was 

 noticeable that the light exercised a very injurious effect 

 within a radius of about six feet. Between six and 

 eight feet the results were indifferent, and beyond that 

 point there was usually a noticeable tendency towards 

 a taller and straighter growth, and it seemed to us that 

 at distances of a dozen feet or more the flowers were 

 more intense in color, particularly when they first 

 opened. There was usually a perceptible gain in earli- 

 ness in the light house, also. 



EXPERIMENTS ELSEWHERE. 



The experiments of C. W. Siemens, in England, and 

 P. P. Deherain, in France, with our own, appear to be 

 the only definite investigations of the subject upon what 

 may be called a practical or horticultural scale. 



At the close of extended experiments , Siemens was 

 very sanguine that the electric 

 light can be profitably employed 

 in horticulture. He had shown 

 that growth can be hastened by 

 the addition of electric light to 

 daylight ; that injury does not nec- 

 essarily follow continuous light 

 throughout the twenty-four hours ; 

 that electric light often deepens 

 the green of leaves and the tints of 

 flowers and sometimes intensifies 

 flavors, and that it aids to produce 

 good seeds ; and he thought that 

 the addition of the electric light 

 enabled plants to bear a higher 

 temperature in the greenhouses 

 than they otherwise could. 



Deherain's experiments were con- 

 ducted at Paris, in 1889. His gen- 

 eral conclusions of the influence of 

 electric light upon plants are as 

 follows : 



1. "The electric light from 

 lamps contains rays harmful to 

 vegetation. 



2. "The greater part of the in- 

 jurious rays are modified by a 

 transparent glass. 



3. "The electric light contains 

 enough rays to maintain full-grown plants two and one- 

 half months. 



4. "The light is too weak to enable sprouting seeds 

 to prosper or to bring adult plants to maturity." 



Finally,, observations were made more recently upon 

 the influence of the electric light upon plants in the 



winter palace at St. Petersburg. It was observed that 

 in a single night ornamental plants turned yellow, and 

 then lost their leaves. 



RECAPITULATION. 



It is impossible to draw many definite conclusions 

 from the above researches. Yet there are a few points 

 which are clear. The electric light promotes assimila- 

 tion ; it often hastens growth and maturity ; it is capable 

 of producing natural flavors and colors in fruits ; it often 

 intensifies colors of flowers and sometimes increases the 

 production of flowers. 



The experiments show that periods of darkness are 

 not necessary to the growth and development of plants. 

 There is every reason, therefore, to suppose that the 

 electric light can be profitably used in the growing of 

 plants. It is only necessary to overcome the difficulties 

 the chief of which are the injurious influences upon 

 plants near the light ; the too rapid hastening of maturity 

 in some ; and, in short, the whole series of practical 

 adjustments of conditions to individual circumstances. 



It is a common notion that plants need rest at 

 night ; but this is not true, in the sense in which animals 

 need rest. If light is continuous, they simply grow 

 more or less continuously, as conditions require. There 



Fig. 7. Influence of Electric Light upon Verbenas. 



is no such thing as a plant becoming worn out or tired 

 out because of the stimulating influence of continuous 

 light. 



On the whole, I am inclined towards Siemens's view 

 — that there is a future for electro-horticulture. 



L. H. Bailev. 



