MOONLIGHT. 63 



As far as is yet known, solar light alone has the power of 

 producing any practical effect upon vegetation. That of the 

 moon has, however, been shown to be not without influence. 

 That the moon has a great mechanical effect upon our globe is 

 undisputed. Of this, we need not say that the perpetually 

 alternate ebbing and flowing of the tide affords the most 

 evident proof. But, whilst the effects of the moon are 

 admitted to be extremely powerful in this respect, the influence 

 of her light, except as regards illumination, has been 

 often considered by scientific men as inappreciable ; and the 

 proverbs to the contrary, cm:rent among the unlearned, have 

 been accordingly estimated as popular errors. It has, however, 

 been at last demonstrated that the moon's rays are very far 

 from powerless. We learn from a note by M. Zantedeschi 

 (Comptes Bendus, October, 1852), that these rays do affect vege- 

 tation. This philosopher states that, " the influence, physical, 

 chemical, and physiological of the moon's light, which has 

 hitherto been the object of so much research and speculation 

 amongst scientific and agricultural writers, has been recently 

 investigated by him in consequence of his having had occasion 

 to give a historical summary of the works on the subject. In 

 the course of his inquiries he found it necessary to clear many 

 doubtful points, in doing which his attention was forcibly 

 arrested by the movements exercised in mere moonlight, under 

 certain circumstances, by the organs of plants ; and this led 

 him to make the whole subject a serious and profound study. 

 His observations were commenced in 1847, in the Botanic 

 Garden at Venice ; they were continued in 1848 in the Botanic 

 Garden at Florence, and at Padua in 1850, 1851, and 1853. 

 In the whole series of his experiments M. Zantedeschi always 

 remarked certain motions in plants having a delicate organiza- 

 tion as soon as they were brought under the influence of 

 the lunar rays. In those experiments the rays were always 

 diffused, being neither concentrated by lens nor mirror. Such 

 movements could not be obtained by the action of heat, in 

 whatever way thermal influences were applied. It was in vain 

 to elevate or depress the temperature : in the absence of 

 moonlight the phenomena in question could not be elicited. 



