70 EXPERIMENT STATION EECOED. 



the blood stream and the cells. This action disappears when the amount of 

 sulphate is reduced, and there then follows a stage of stimulation, the sulphate 

 causing a very marked diuresis, sometimes accompanied by the excretion of 

 much more sulphates than were injected into the body together with the amount 

 found in the food. Sulphate also has a marked irritant action on the kidney 

 cells when more than a small amount is present. Purgation is not usual ; during 

 the second day after an injection an increased quantity of sulphates is excreted 

 in the feces, but the following day the amount has again fallen to normal. 

 Calcium carbonate, phosphate, and oxalate are found in the urine after large 

 doses, and arc probably products of incomplete oxidation, the oxidation having 

 been interfered with by the high concentration in the blood preventing inter- 

 change with the cells. 



" Hyposulphites act very much like sulphates, being very quickly reduced in 

 the body to sulphate. 



" Sulphites and sulphids are somewhat similar in their action, and this action 

 depends on the amount of oxidizing ferments found in the animal. In some 

 animals they are at once oxidized, and the sulphates produced give the typical 

 picture described above. If the animal is deficient in oxidizing ferments the 

 sulphite appears to unite with and neutralize the action of the tissue ferments. 

 Sulphid appears to unite to some constituent of the cell itself, and both interfere, 

 according to the quantity, with tissue changes, and if in sufficient amount they 

 stop all metabolic changes and the animal dies of failure of respiration and 

 circulation, with perhaps convulsions. If the amount is sublethal, it is attacked 

 by the oxidizing ferments, and gradually got rid of as sulphate. In the case of 

 sulphite, when the toxic dose is large the sulphate gives the diuretic action, 

 but in the case of sulphid the amount of sulphate is so minute that little or no 

 diuresis is often to be seen. Both sulphite and sulphid interfere with metabolic 

 changes, especially with oxidation processes, causing the excretion of calcium 

 especially, but also of other insoluble salts in the form of carbonate, phosphate, 

 and oxalate. There is also an intense renal irritation as the result of both these 

 salts. The irritation caused by all these three sulphur compounds raises the 

 possibility as to whether they may not, in part at least, be the cause of chronic 

 nephritis and cirrhosis of the liver, both frequently ascribed to malted drinks, 

 which are known to contain large amounts of sulphates. When it is also con- 

 sidered that these people usually have insoluble salts in their urine, such as 

 are described in this paper, and as such results are not common after drinks 

 which are free from sulphates, it is possible that the sulphates, and not the 

 alcohol, may be the cause of their condition." 



Studies in nutrition. — An investigation of the influence of saltpeter on the 

 nutrition and health of man with reference to its occurrence in cured meats: 

 III, The experimental data of the bio-chemical investigations, H. S. Gbindley 

 ET AL. (Univ. III., 1911, pp. VIII+4^2). — This volume of studies in nutrition 

 carried on at the University of Illinois reports experimental data of the extended 

 investigations of the influence on the nutrition and health of man of saltpeter 

 as it occurs in cured meats. The methods of analysis followed are described 

 and the kind and amounts of food eaten, as well as the chemical composition of 

 food and excretory products, are recorded. The fat balance and coefficient of 

 digestibility of fat are recorded, as are also data regarding the volume, specific 

 gravity, acidity, and chemical composition of the urine. The recorded data are 

 not discussed with reference to their bearing on the general question under 

 consideration, the volume as a whole being one of a series. The records of food 

 consumption constitute a very extended dietary study or feeding experiment 

 under carefully controlled conditions. 



