vii KATABOLIC CONSTITUENTS OF UEINE 407 



Succi, as also I. Munk on Cetti, observed a progressive diminution 

 of the chlorine content from the commencement to the end of the 

 fast. During inanition, when the plasma and tissues are very 

 poor in sodium chloride, ingestion of this salt produces no corre- 

 sponding rise in its excretion. On resuming the normal diet a 

 considerable amount of the salt given with the food is retained for 

 two or three days. 



Pathological observations support these facts. In febrile 

 maladies in general, especially in pneumonia, rheumatic arthritis, 

 and typhoid, there is a very marked diminution in the sodium 

 chloride excretion by the urine (liypochloruria). According to 

 Salkowski this is not merely the result of the decreased consumption 

 of salted foods, but is a true retention of chlorine in the body. In 

 fact, sodium chloride excretion rises again without ingestion of 

 food, as soon as the crisis of the illness is over. In one case of 

 pneumonia, the sodium chloride excreted fell to 1-1 -6 grin, per 

 diem, and rose again after the crisis to 7 - S7 grins., and on the 

 next day to 16'1S grms. This fact cannot be explained simply 

 by reabsorption of the exudate, the molecular concentration of 

 which is always isotonic with blood plasma (Winter and others) 

 one of the most important functions of the sodium chloride in the 

 blood being to maintain equilibrium in the osmotic pressure of the 

 tissue fluids. 



The sulphuric acid excreted in the urine, either in the form of 

 nil-aline sulphates or combined with the aromatic products in the 

 form of ethereal sulphates, amounts as a whole in adults, with a 

 mixed diet, to T5-3 grms. per diem calculated as S0 3 (Fiirbringer 

 and Neubauer). As a rule, the amount of sulphates introduced 

 with the food is scanty, and even when abundantly supplied in 

 the form of magnesium or sodium sulphate the greater part of 

 these salts are eliminated by the intestine, on which they act as a 

 cathartic. The sulphuric acid of the urine thus originates almost 

 exclusively from the oxidation of the sulphur of the proteins 

 introduced with the food, or from the tissue protein consumed. 

 The variations of the sulphuric acid in the urine are therefore 

 almost parallel with those of the urea, both being decomposition 

 products of protein. 



The amount of sulphuric acid combined with the aromatic 

 ethers is on an average y 1 ^- the total sulphuric acid, but this ratio 

 is subject to many pronounced oscillations according to the nature 

 of the diet and the varying intensity of the putrefactive processes 

 of the intestine (supra, p. 395 et seq.}. 



The whole of the sulphur contained in the urine does not 

 appear as sulphuric acid : part of it is present in the form of 

 organic compounds of which some only are known to us. Salkowski 

 gives the name of neutral sulphur to these, to distinguish them 

 from the preceding or acid sulphur. Neutral sulphur constitutes 



