Morning journal and courier., 1880-04-03
Dr. Siemens' DiscOvery-The Electric
 Light and Vegetation.

From the London Times
 Dr. c. W. Siemens gave at 8 recent meeting of the Royal Society description of some ex- perimsnts upon the above subject which have been conducted during the last two months at his house at Sherwood, and exhibited spec imens. The method pursued was to plant quick-growing plants-such as mustard, car rots, swedes, beans, cucumbers and melons- in pots, and these pots were divided into four groups, one of which was kept entirely in the dark one was exposed to the influence of the electric light only, and one to daylight and electric light in succession. The electric light applied for six hours each evening-from to Hand the plants were then left in darkness during the remainder of the night. The general result was that the plants kept entirely in the dark soon died, those exposed to the electric light only or to daylight only throve about equally, and those exposed to both day and electric light throve far better than either, the specimens of mustard and of carrots exhibited to the society showing this difference in a very remarkable way. Dr. Siemens only considers himself yet on the threshhold of the investigation, but thinks the experiments already made are sufficient to jus tify the following conclusions: l. That elec- tric light is efficacious in producing chlorophyl in the leaves of plants and in promoting growth. 2. That electric centre of light equal to 400 candles placed at a distance of two metres from growing plants appeared to be equal in effect to average daylight at this season of the year but that more economi- cal effects can be obtained by more powerful light centres. 3. That the carbonic acid and nitrogenous compounds generated in diminu- tive quantities in the electric arc produce no sensible deleterious effects upon plants en- closed in the same space. 4. That plants do not appear to require period of rest during the twenty -four hours of the day, but make increased and vigorous progress if subjected during daytime to sunlight and during the night to electric light. B. That the radiation of heat from powerful electric arcs be made available to counteract the effect of night frost, and is likely to promote the set ting and ripening of fruit in the open air. 6. That while under the influence of electric light, plants can sustain increased stove heat without collapsing, circumstance favorable to forcing by electric light 2. That the ex- pense of electro horticulture depends mainly upon the cost of mechanical energy, and Is very moderate where natural sources of such energy, such as waterfalls, can be made avail able The paper gave rise to a highly inter that the evidence afforded of the practical identity, as regards vegetation, of solar and electric light, besides the probability that it would be turned to immediate account by hor- ticulturists, would afford great facilities for the scientific investigation of the influence exerted by light, as compared with other agencies, in promoting the formation of the active principles or most valuable constituents of plants such as the quinine of the cinchona bark, the gluten of wheat and so forth Be- fore concluding his observations Dr. Siemens placed a pot of pudding tulips in the full brightness of an electric lamp in the meeting room, and in about 40 minutes the buds had expanded into full bloom.y