THE CHEMISTRY OE THE ANIMAL BODY. 531 



THE CHEMISTRY OP THE COMPOUNDS OF CARBON. 



Derivatives of Methane. 



The complicated structure aud the great variety of the compounds of car- 

 bon are due to the fact that carbon-atoms have a greater power for union 

 with one another than have the atoms of other elements. 



Saturated Hydrocarbons or Paraffins (formula, C„H 2n + 2 ). — 



Methane, CH 4 , gas. Pentane, C 5 H 12 , liquid at 38°. 



Ethane, C 2 H 6 , " Hexane, C 6 H 14 . " 71°. 



Propane, C 3 H 8 , " Heptane, C 7 H 16 , " 98°. 



Butane, C 4 H 10 , " etc. 



These are the constituents of petroleum and natural gas, and are formed by the action 

 of low heat on coal under pressure in the absence of oxygen, and are probably derived 

 from fossil animal fat, since it has been shown that the paraffins may be obtained in large 

 quantity by beating fish oil at a pressure of ten atmospheres. 1 The paraffins may all be 

 formed synthetically from methane by the action of sodium on halogen compounds of the 

 group : 



2CH 3 I + 2Na = C 2 H 6 + 2NaI. 



C 2 H 5 I + CH3I + 2Na = C 3 H 8 + 2NaI. 



This may be continued to form a theoretically endless number of compounds. Paraffins are 

 notably resistant to chemical reagents, not being affected by either concentrated nitric or 

 sulphuric acids. Vaseline contains a mixture of paraffins melting between 30° and 40°. 

 By massage vaseline may be absorbed by the skin, through the epithelial cells of the seba- 

 ceous glands. In rabbits and dogs, directly after such treatment, it may be detected de- 

 posited especially in muscle, but it is for the greater part destroyed in the body. 2 



Monatomic Alcohol Radicals. 



These are radicals which may be considered as paraffins less one atom of hydrogen, and 

 therefore having one free bond. They form the basis of homologous series of alcohols 

 and acids. 



Monatomic Alcohols (general formula, C n H 2n + jOH). — 



Methyl alcohol, CH,OH. Amyl alcohol, C 5 H„OH. 



Ethyl alcohol, C 2 H 5 01I. Hexyl alcohol, C„H 13 OH. 



Propyl alcohol, C B H T OH. Heptyl alcohol, C T H u OH. 

 Butyl alcohol, C 4 H 9 OH. etc. 



General Reactions for Primary Alcohols.— (1) Alcohols treated with sulphuric acid 

 give ethers (see Ethyl ether) : 



2CH3OH + h 2 so 4 = ch:;>° + H *° + H2SOi< 



Methyl ether. 

 (2) Alcohols oxidized give first aldehyde and then acid : 

 CH s OH + = HC ^g + H 2 0. 



Methyl aldehyde. 



CH 2 + = HC<£J H 



Formic acid. 



1 Engler: Berichte der deutschen chemischen OeseUachaft, 1888, Bil. 21, S. 1816. 



1 Soubiranski : Archivfiir exper. Pathologie und Pharmakologie, 1893, Bd, 31, S. 329. 



