THE HORTICULTURAL SOCIETY OF NEW YORK 



We shoukl not leave this first experiment withont giving one of 

 the most important conclusions by Dr. Siemens : 



"Periodic darkness evidently favors growth in the sense of 

 elongating the stalks of plants, the continuous stimulus of light 

 appears favorable for healthy development at a greatly accelerated 

 pace, through all the stages of the annual life of the plant, from the 

 early leaf to the ripening fruit. The latter is superior in size, in 

 aroma, and in color to that produced by alternating light, and the 

 resulting seeds are not' at any rate devoid of re-germinating 

 power." 



We are also interested in the cost of these experiments. Dr. 

 Siemens states that nine lights over three-fourths acre of glass 

 cost 1 6 shillings per day. 



While scientists in England, France and Germany were testing 



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Fig. I. — Growth curves for following plants — i-A and i-B Ivy, 2-A and 2-B Boston Fern, 3-A 

 and 3-B Calla Lilies, 4-A and 4-B Tradescantia or Wandering Jew. 5-A and 5-B Geranium (apple 

 scented). 



30 



