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New Zealand Herald, Volume XXXI, Issue 9492, 23 April 1894, Page 5

Experiments are still being carried on ay experts in America to test the effects of the electric light on the growth and development of plants in greenhouses. A third report on the subject was recently published in a bulletin of the Cornell University Station. Professor Bailey commences the report with the following paragraph :— "For four winters we have made a study of the influence of the electric arc lamp upon plants grown in greenhouses. The results of these investigations, so far as published, appear in Bulletins 30 and 42. During two winters the lamp was hung inside the house, and part of the time the light was naked and at other times screened by a glass globe. lb was found that lettuce was greatly hastened in growth by the light, and various flowers were earlier and brighter under its influence. Many plants were injured by the naked light, but sustained no injury, or were even benefited by a light which was modified by passing through an opal globe or even through common glass. It therefore seemed reasonable to expect that if the lighb were placed above the house the glass roof would afford a sufficient screen, and this feature of the investigation was the particular subject of the bulletin last year (Bulletin 42, September, 1892). It was found that radishes and other plants which were injured by a naked light inside the house and even by a light modified by an opal globe, were benefited by a light above the roof; and lettuce and flowers still showed a marked benefit from it. This experiment was repeated last winter, and the results are given in the sequel. We also continued our observations upon the effect of coloured glass screens interposed between the lamp and the plants for the purpose of ascertaining what part of the spectrum influences plants inquiry which we mentioned last year bub upon which no reporb has heretofore been made. Finally, we have to report a preliminary investigation to determine to what distance the influence of the light extends." lb appears that in the case of cauliflowers the results of the electric lighb are somewhat conflicting, the lighb having very little influence on these vegetables, except when placed too near, when ib is injurious.