THE CHEMISTRY OF THE ANIMAL BODY. 977 



Trichlormethane, or Chloroform, CHC1 S . This temporarily paralyzes nerves and 

 nerve centres. It is principally removed as vapor through the lungs, but is partially 

 burned, thereby increasing the inorganic chlorides in the urine. l After giving chloroform 

 it may itself occur in the urine, and likewise a substance which reduces Fehling's solu- 

 tion, glycuronic acid (which see). 



Methyl Aldehyde, or Formic Aldehyde, H.CHO. This may be pro- 

 duced synthetically by passing vapor of methyl alcohol mixed with air over 

 an ignited platinum spiral, 



CH 3 OH + O = H.CHO + H 2 O. 



On cooling the vapor, the aldehyde is found dissolved in the alcohol. On 

 evaporation of the alcohol, the aldehyde, through condensation of three of 

 its molecules, forms a crystalline body having the composition (HCHO) 3 and 

 called paraformic aldehyde. This latter treated with calcium or magnesium 

 hydrate again suffers condensation with the production of fomiose, C 6 H 12 O 6 , a 

 sweet-tasting sugar (Butlerow, Loew) identical with i-frtictose (Fischer). 

 Baeyer 2 first suggested that the sugar synthesis in the plant was analogous 

 to the above process. He conceived the reduction of carbon dioxide to 

 carbon monoxide, which united with chlorophyll, and afterward through 

 hydrogen addition became formic aldehyde; then in upward stages became 

 metaformic aldehyde, sugar, starch, and cellulose. Reinke 3 has shown the 

 presence of formic aldehyde in chlorophyll leaves, and believes its produc- 

 tion due to the reduction of carbonic acid through the power of the sun 

 on the leaf, thus : 



H 2 CO 3 = HCHO + O 2 . 



Bach 4 states that carbonic acid and water in the presence of uranium acetate 

 yield formic aldehyde and nascent oxygen when placed in the sun. According 

 to Stocklasa, 5 400 grams of fresh leaves (128 grams dry) of the sugar beet 

 form synthetically and send to the beet root 31 grams of cane-sugar in 

 thirty days. 



General Behavior of Aldehydes. They act as reducing agents, being readily oxidized 

 to the corresponding acid. With nascent hydrogen they are reduced to alcohols. A dis- 

 tinctive reaction of aldehydes and ketones is their union with phenyl hydrazin, C 6 H 5 

 NH NH 2 , giving hydrazones : 



CH 3 CHO + C 6 H 5 NHNH 2 = CH 3 .CH:N.NH.C 6 H 5 + H 2 0. 

 Preparation. By distillation of the salt of an acid with a salt of formic acid : 

 CH 3 COONa + HCOONa = Na 2 C0 3 + CH 3 CHO. 



Aceto-aldehyde. 



Methyl Mercaptan, CH 3 SH. This is a product of bacterial action on 

 proteid, 6 and is found with H 2 S in the intestine. It is, furthermore, 



1 A. Zeller: Zeitschrift filr physiologische Chemie, 1883, Bd. 8, p. 74. 



2 Berichte der deutecften chemischen Gesellschaft, 1870, Bd. 3, p. 67. 

 8 Ibid., 1881, Bd. 14, p. 2144. 



4 Ibid., 1894, Bd. 26, pp. 502 and 689. 



6 Stocklasa: Zeitschrift fur physiologische Chemie, 1895, Bd. 21, p. 83. 

 8 M. Nencki : Archivfur txper. Pathologic und Pharmakologie, 1891, Bd. 28, p. 206. 

 62 



