66 MASSACHUSETTS HORTICULTURAL SOCIETY. 



by the injuries resulting from the unscreened arc. Subsequently 

 we have found that the use of a glob-e or pane of glass will avert 

 the injuries to flowers as well as to foliage, and the long stems 

 and open inflorescence, together with increase in earliness in some 

 cases, may be obtained without fear of injury. Yet we are not 

 ready to recommend the electric arc lamp for the growing of 

 flowers. 



If the noxious effects of the electric light can be overcome by 

 the interposition of glass, it remained to determine whether the 

 light can be hung above the house to advantage, the glass roof 

 serving as the screen. A lamp, surrounded by a globe, was hung 

 six feet above the middle of a glass roof, and lettuce, endive, 

 beets, radishes, and spinach, and other plants, were grown 

 beneath. The lamp was so arranged that half the house had no 

 electric light, while the other half received the full glare of the 

 arc. The lettuce, as usual, was from a week to ten days earlier 

 in the lighted compartment, and the effect was marked in the 

 remotest corner of the house, forty feet from the lamp. Endive, 

 Avhich had been injured in other experiments, now showed no bad 

 results, although it did not appear to be benefited ; but radishes, 

 which had been among the plants most seriously injured in all our 

 experiments, now showed for the first time a decided gain in the 

 light compartment, indicating that at a certain degree of attenua- 

 tion, the light may be made acceptable to any plant. The plants 

 in the light house were ahead in every feature. The proportion 

 of tops to the entire plant was greater in the light than in the dark 

 house, the difference being that between 55 per cent and 49 per 

 cent. In 1890, under the naked light, radishes were uniformly 

 injured, the loss ranging from 45 to 65 per cent ; the same year, 

 under a light protected by an opal 'globe, the injury was still 

 apparent, but the loss in tubers was only from one to five per cent 

 of the crop, but at the same time the weight of leaves was 

 increased ; now this year, under light strained through a globe 

 a'nd a glass roof, there was an increase in both tubers and tops. 

 Similar results were obtained with beets and spinach ; but cauli- 

 flowers were decidedly better in the dark house, thus adding a new 

 source of perplexity, the discussion of which will be resumed 

 presently. 



Violets and daisies were also grown in this experiment. In 

 botli instances, strong plants were set in the beds a few days 



