420 



THE UNIVERSE. 



CHAPTER IV. 



TRANSPIRATION IN PLANTS. 



Vegetable pli3'siolog7 approaches ver)- nearly that of 

 animals. Like them plants exhale moisture abundantly 

 by their whole surface. It is this which, condensed 

 upon the leaves by the cold of night, forms on them 

 limpid little droj^s of water, which the vulgar incorrectly 

 ascribe to a deposit of atmospheric moisture. 



The idea that plants transpire like animals is due to 

 Muschenbroeck, one of the professors Avho have contri- 



:^^^ 



228. Discovery nf the Transpiration of Plants. — Muschenbroeek's experiment. 



buted most to rendering the university of Leyden illustri- 

 ous. For this purpose he covered with a plate of lead the 



