SUCCESS IN MARKET GARDENING 

 calculations it has been common to reckon from 

 the glass surface actually present in the given case. 

 A method still more precise consists in reckoning 

 from the whole exposed surface of the structure; 

 glass, sides and ends; rating the two latter as of 

 one-third the radiating effect resulting from a 

 similar surface of glass. 



ELECTRO-CULTURE. In my Arlington green- 

 house above mentioned is afforded an example of 

 successful and profitable use of the electric light 

 in stimulating plant growths. Four 10-ampere, 

 45 volt, Brush arc lamps of 2,000 nominal candle- 

 power are employed, when the beds are occupied 

 with lettuce, with the effect of causing the growth 

 of this crop to be maintained continuously instead 

 of being intermitted at night; this saves time, if 

 not quite proportionately, at least in a material 

 degree; accelerating the maturity of the crop, and 

 enabling the cucumber plants, which are to follow, 

 to begin their growth so much the earlier. 



I have not yet extended my use of the electric 

 light to the culture of other crops than lettuce; 

 and believe there is ground for thinking that some 

 at least will be injured, rather than benefited by 

 that treatment. Except in the case of lettuce, 



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