376 Hilda Kincaid : 



element than any other, in fact the body tries to hold back no 

 other element as energetically as it does phosphorus. Tt deals 

 with phosphorus in a more economic manner than Avith nitro- 

 gen, for with increased nitrogen intake the body immediately 

 responds by increased nitrogen output to preserve the nitrogen 

 equilibrium. With increased phosphorus intake, however, 

 equilibrium is not established, but some of the phosphorus is 

 retained (11). The amount of phosphorus actually absorbed 

 from the alimentary canal depends on the kind of food — in 

 vegetable foods which contain a large quantity of calcium a 

 good deal of the phosphorus is left behind in the faeces as in^ 

 soluble calcium pho'sphate ; in meat feeding, on the contrary, 

 most of the phosphorus in the faeces is due to actual intestinal 

 secretion. In the food phosphorus is taken in for the most part 

 in organic combination as nucleoalbumen, nucl^in, casein, 

 lecithin, etc., in eggs, milk, leguminous vegetables, and only 

 in small degree in inorganic combination as in grains, and 

 meat. 



The experiments of Hart, McCollum and Fuller at the Wis- 

 consin Agricultural Experiment Station (12) show how im- 

 portant is a normal supply of P.^ O, in food. Animals fed on 

 food deficient in this constituent very soon became abnormal, 

 exhibiting weakness of limbs, langour, debility, and if the ex- 

 periment continued long enough, finally death ; whilst if the 

 diet was nuide normal again the animals gradually recovered. 

 A disease, allied to rickets, is often found in cattle living on 

 natural foods poor in calcium phosphate. In nearly all cases it 

 is found if phosj^hates are added to the diet they are quickly 

 absorbed with remedial effect ; but a much better effect is 

 gained by the addition to the diet of organic phosphoi-us com- 

 binations than by the addition of only the inorganic salts. The 

 res\ilts of the experiments of Le Clerc and Cook (2-1) seem to 

 point to the fact that organic pliospliorus t.ixouis iiitrni;en 

 metabolism, and increases nitrogen and ])liospliorus retention, 

 especially in the case of a phosphorus poor food. 



Tlie researclies of Cronheini and Miiller (13) on c-hihlren, 

 and those of Rohmann, Ehrstrom and Guin[)('rt (2")), liave 

 shown organic phosphoi-us feeding to be superior to inorganic 

 for frrowth and nourishment, and for this reason human milk is 



