SCHULTZENSTEIN — NUTRITIVE CONSTITUENTS OF WATER. 110 



hydrates, as oil of lemons, oil of turpentine, india-rubber. Oil 

 of lemons, according to Th. de Saussure, contains 86*89 C, 

 12 '32 H, proportions which are absolutely contrary to the hydrate 

 theory. 



In DeCandolle's ' Physiology of Plants,' as translated by Roper 

 (vol. i. p. 364), we find a table of the elementary composition of 

 many vegetable substances, from which an addition may easily be 

 made to the instances which have been brought forward. 



It is abundantly clear, then, that, in the nourishment of plants, 

 water cannot be used for the formation of hydrated carbons with 

 the carbon derived from the carbonic acid of the air — that it must 

 be useless in practical gardening and agriculture to attempt to 

 nourish plants with pure water and carbonic acid without any 

 humous constituents, as, in fact, all attempts to nourish plants 

 with carbonic acid and water have miscarried. 



Another view of the agency of water in the nutriment of plants 

 is that of Berthollet, that a decomposition of water takes place in 

 such a manner that the hydrogen is assimilated, but the oxygen 

 set free. Saussure contradicted this completely, by showing that 

 the water always runs unaltered through the plant, whose sub- 

 stance never increases by the assimilation of water. Notwith- 

 standing which, Liebig, altogether unacquainted with Saussure's 

 experiments, has sought a new explanation of Berthollet's theory, 

 without troubling himself previously about the truth of the 

 grounds on which it depends, and without making a single experi- 

 ment on the subject. Liebig supposes that we must explain the 

 decomposition of water after the analogy of the contact of zinc, 

 water, and carbonic acid, where the zinc rusts in the water and 

 the oxide of zinc unites with the carbonic acid to form carbonate 

 of zinc. The living plant, according to this view, acts as zinc in 

 galvanic decomposition. This is an addition to Liebig' s numerous 

 explanations of circumstances of organic life, which are not 

 present in nature, but are mere fancies, since decomposition 

 and assimilation of water do not take place in plants, as appears 

 from every experiment ; but suppose there were such processes, 

 the view which would make plants galvanic batteries is just as 

 though a man should explain living growth out of decomposition, 

 as indeed is sometimes the case, or compare a living plant with a 

 stinking dunghill. The gardener and cultivator can only be puzzled 

 by such lifeless explanations. His first principle should be that 

 in the cultivation of plants he has to do with living beings, which 

 he must keep alive, and not sacrifice by galvanic experiments. 



