184 OXYGEN YIELDED BY ANIMALCULES. 



gases which constitute the atmosphere. We find 

 them in fact always and everywhere the same. 

 Infinite Wisdom has provided, therefore, that as 

 there is an enormous demand on one of its elements, 

 so of this there should be as ample a supply. 



In a very interesting memoir by Messrs. August 

 and Morren, contained in the Transactions of the 

 Academy of Brussels for 1841, it is shown that 

 water with organic substances evolves a gas which 

 contains sixty-one per cent, of oxygen ; and they 

 conclude their treatise by saying : "It follows from 

 the preceding remarks, that the phenomenon of the 

 evolution of oxygen gas is due to the Chlamido- 

 nomas pulvisculus, Ehrenberg, and to several green 

 animals still lower in the scale." 



In Liebig's Chemistry, this statement is quoted, 

 and that eminent man then proceeds to remark: "The 

 author took the opportunity of convincing himself 

 of the accuracy of this long -observed fact, by means 

 of some water out of a trough in his garden, the 

 water being coloured strongly green by different 

 kinds of infusoria. This water was freed, by means 

 of a sieve, from all particles of vegetable matter, 

 and being placed in a jar inverted in a porcelain 

 vessel containing the same water, was exposed for 

 several weeks to the action of solar light. During 

 this time a continued accumulation of gas took 

 place in the upper part of this jar. After fourteen 

 days, one-third of the water in the jar had been 

 pressed out of it, and the gas which had taken its 



