318 HENRY A. MATTILL AND HELEN I. MATTILL 



be deficient in Ca (McCollum, Simmonds and Parsons). The ingestion of 

 excessive quantities of fat, protein or carbohydrate increases lime ex- 

 cretion (Kochmann(a) (&)). N and Ca balances show no parallelism wliat- 

 ever. 



Albu-Neuberg state that NaCl increases and that alkalies reduce CaO 

 resorption: neither v. Wendt nor Givens support this statement, Aron 

 found that high K and low Na intake decreased Ca absorption, but Adler 

 was not able to confirm this. Dubois and Stolte by adding alkali to the 

 diet of rachitic children were able to convert a negative to a positive lime- 

 balance, but if the balance was originally positive the addition of alkali had 

 little effect. Neither Givens nor Granstrorn were able to show any effect of 

 alkali or acid administration on the lime balance of a dog. Secchi on the 

 other hand found in dog and man an increased Ca output, especially in the 

 feces, when HC1 was administered. Undoubtedly the nutritive condition 

 of the individual at the time such an experiment is initiated influences 

 the result ; Givens' dogs were on a minimum or even inadequate Ca intake, 

 while Secchi's subjects showed a positive Ca balance. An addition of 

 H 3 PO 4 causes an increased CaO output in both urine and feces. 



In the adult there is a tendency to Ca equilibrium. Renvall increased 

 the lime intake over the amount necessary for equilibrium by ingesting 

 CaCO 3 and found a retention of CaO for several days, followed by equilib- 

 rium on a higher level of intake and output. This is strikingly like pro- 

 tein and NaCl metabolism, and is confirmed by Sherman and by Herbst. 



In infancy and childhood the question of lime metabolism, as of phos- 

 phorus, becomes one of especial importance because of the need of the 

 body for these elements in growth and especially in bone formation. 

 Weiser has shown in work on dogs that gain in weight, on a diet poor 

 only in Ca, is below normal, and surprisingly enough, the bones make up 

 a larger percentage of the total body weight than in the control animals. 

 The water content of the bones was 20-30 per cent higher than that of 

 the controls, the ash content lower, and the fat content about the same. 

 The composition of the ash varied from the normal and the variation was 

 greatest in the ribs and least in the skull, and was characterized by de- 

 creased Ca, P 2 O 5 an d SOo, and by the appearance of 3-5.5 per cent Na 2 O 

 and 0.35-1.25 per cent K.jO. Aron and Sebauer confirm this. E. Yoit 

 found the breast bone and skull of pigeons to be most affected by a Ca free 

 diet. Ai'on(d) and Bruning in work on growing rats which they main- 

 tained at constant weight by underfeeding on an otherwise adequate diet, 

 or by food containing only carbohydrate, found a markedly increased 

 percentage of ash in the total body, as compared with control animals of 

 the same weight but younger. 



The amounts of the mineral elements required to make a gain of 100 

 g. in the body weight of infants have been calculated from various angles. 

 Camerer and Soldner based their estimate on the composition of new-born 



