40 SCIENCE AND SOIL 



chiefly of allyl * sulfid (C 3 H 5 ) 2 S; and mustard oil is also composed 

 of organic sulfur compounds. 



Phosphorus. Phosphorus is the Greek word for the morning 

 star, and signifies light. The element phosphorus is closely asso- 

 ciated with the beginning of all forms of mortal life. The nucleus 

 of every living cell in plants and animals is rich in phosphorus. 

 Nuclein, the phosphorized nitrogenous constituent of the cell- 

 nucleus, contains as high as 10 per cent of the element phosphorus, 

 although it may contain no sulfur. The following formula has been 

 suggested byMiescher for nuclein derived from animal cells: 



C 29 H 49 22 N 9 P 3 . 



Lecithin, C 44 H 90 O 9 NP, is a well-known organic phosphorus com- 

 pound, which it is thought may have some controlling influence in 

 the formation of fats and oils. Ordinary corn contains about 5 

 per cent of oil, of which 1.5 per cent consists of lecithin; that is, 

 i^ pounds of lecithin are found in 100 pounds of the oil. 



It should be remembered that, while sulfur is contained in many 

 proteids, phosphorus is present in every cell of every plant. The 

 grain or seed of plants contains, as a rule, more than fifty times as 

 much phosphorus as sulfur. The phosphorus of the corn kernel is 

 found largely in the germ. In 1000 pounds of corn there are about 

 100 pounds of germs containing more than two pounds of the ele- 

 ment phosphorus. About 95 per cent of the ash obtained from the 

 burning of corn consists of the phosphates of potassium and 

 magnesium. Hay, straw, and other coarse products usually 

 contain more sulfur than the grain, but these coarser parts com- 

 monly remain on the farm, while the grain is more likely to be sold. 



1 The monovalent allyl group ( CsHs) differs from the trivalent glyceryl 

 (=CsH6) only in having a double bond, as shown in allyl alcohol and glycerin 

 (which might also be called glyceryl alcohol) : 



Allyl alcohol Glycerin 



CH 2 CH 2 OH 



II I 



CH CHOH 



I I 



CH 2 OH CH 2 OH 



