80 SMITH : EFFECT OF THE MOON's PHASES OF THE 



Experiments liave been Ctarried out in Soiitli India to test 

 the theory of the effect of the moon's ])liases. Tliese liave been 

 complicated by the fact that certain remedial measures have 

 been undertaken at the same time, viz., prolonged soaking in 

 water immediately after felling and also covering the felled 

 bamboos from the Hght. There has not been therefore any 

 decisive test of the effect of the moon's phases, but, as far as 

 it can be ascertained, they lend no support to the native suppo- 

 sition. We have therefore no well-attested facts in support of 

 the idea, and there is really therefore nothing to be explained 

 by any facts known to science respecting the bamboo. It may, 

 liowever, be worth while for me to indicate along what lines a 

 connection l^etween known facts and the native supposition may 

 be expected if on any, and also to provide a tentative explana- 

 tion of certain facts which seem to be the outcome of the experi- 

 ments in South India. The amount of water present in the 

 culms, whether mature or growing, of the giant bamboo 

 depends largely on the humidity of the atmosphere, and to 

 some extent on the intensity of light also. Thus, at night at 

 Peradeniya, when the light is very feeble and the humidity of 

 the atmosphere very liigh, the adult culms are full of water 

 which rapidly oozes out in drops when any injury is made, such 

 as knocking a nail mto the culm. At this time also the young 

 growing culms are so saturated vnth water tliat this oozes out 

 spontaneously from the tips and axils of the bracts of the 

 slieathing leaves. The supply of water is no doubt due to the 

 activity of the root system which forces by root pressure a 

 copioussupply into tlie culms above , whether adult or immature. 

 Now, in the daytime this supply is required to replace the 

 rapid loss from the extensive leaf system of the adult culms. 

 It happens therefore that there is a rapid transpiration current 

 along the adult culms and the water is removed as fast as it is 

 supplied from the roots. To be strictly accurate in fact the 

 upward suction of the leaf system combines with the root pres- 

 sure to produce a current of water more rapid than would be 

 the result of root pressure alone. Not only does the k)ss of 

 water from the leaves produce a rapid transpiration current in 

 the adult culms, but it also appropriates the supply for the 

 growing cuhns wliicli arc on the same rliizome system. 



