i66 



THE ENERGY OF THE LIVING PROTOPLASM. 



to arouse the envy of the chemist and instigate him to try to 

 accomplish the same ends. To these endeavours we owe a long 

 series of interesting syntheses since the artificial preparation of 

 urea by Wdhler in the year 1828. Carbon and hydrogen were 

 united in the electric arc by Berthclot ; acetylene, thus formed, 

 leads, among other things, to ethylene, ethyl alcohol, acetic acid, 

 aldehyde, acetone, and glyoxal. Acetylene yields at low red 

 heat benzene, from which, again, numerous derivatives can be 

 obtained. Acetone, further, may easily be converted into 

 trimethyl-benzene, aldehyde into trimethyl-pyridine ; from pyri- 

 dine, again, conine may be reached (Ladcnbur«). Glyoxal leads, 

 bv way of its cyanhydrin, to tartaric acid. 



Carbon can be united with aluminium and this product 

 fields, by decomposition with water, methane (Moissan). Methane, 

 again, yields methyl alcohol and formaldehyde, while the latter 

 yields by condensation several kinds of sugars (0. Loew). 

 Formic acid can be obtained by the action of sodium upon moist 

 carbon dioxide (H. Kolbc), or by the action of iron filings upon 

 bisulphide of carbon in presence of water in sealed tubes at 

 ioo° (O. Loew). Oxalic acid results by passing dry carbon 

 dioxide over hot sodium amalgam (E. Drcchsel), or by treating 

 the product of reduction of bisulphide of carbon by sodium 

 amalgam with fusing potash or boiling baryta water (0. Loew). 

 From a mixture of oxalic ester and acetic ester aconitic acid can 

 be obtained (L. Claiscn and E. Hori) ; from acetone and oxalic 

 ester, oxytoluic acid, and from this an anthracene derivative, 

 (dimethyl-anthrarufin) was obtained {Claiscn). From malonic 

 ester phloroglucin can be reached [A. Bacycv), from succinic 

 ester hydroquinone, from malic acid oxynicotinic acid and 

 daphnetin (Pcchmann). 



These and similar synthetic processes, are, however, for the 

 most part only possible by the application of powerful agents, 

 such as strong bases or acids, sodium alcoholate, sodium 

 amalgam, chloride of zinc, etc., and partly by the aid of high 

 temperature ; while no light is thrown upon the special method 

 followed by the living protoplasm of plant-cells, a material consist- 

 ing of proteids of neutral reaction or nearly so, and very easily 

 changed by any substance with powerful affinities. The chemical 

 agency consists here merely of specific waves. We are acquaint- 



