836 



GENERAL DISORDERS OF NUTRITION. 



for long periods together, to evacuate a larger weight of urine and 

 faeces than they had taken in of food and drink, without losing in 

 weight. Every investigator and experimenter, who has given his at- 

 tention to the subject of diabetes, has to suffer from the strong in 

 clination on the part of the patient to deceive him, and to conceal a 

 portion of the liquid that he drinks. In the researches and experi- 

 ments of Reich and Liebermeister at the Greifswalder clinic, the re- 

 sults of which have been published by Dr. Reich, at first, the quantity 

 of urine and faeces, evacuated by both of the patients under observa- 

 tion, seemed to exceed the amount which they ate and drank. But 

 after they began to watch the patients so closely that they were never 

 left alone for a moment, nor withdrawn from immediate observation, 

 the quantity of ingesta began to exceed that of excreta of urine and 

 faeces. 



With regard to the cause of the immense increase in the secretion 

 of urine in diabetes, Liebermeister and Reich have proved by their 

 experiments that the very large quantity of liquid which they imbibe 

 is not of itself sufficient to account for it. For a number of days, and 

 with great care, they measured out equal portions of food and drink to 

 two patients with diabetes, and a similar portion to a perfectly healthy 

 and trustworthy man (Mr. Hoffmann, student of medicine), and meas- 

 ured the flow of urine for every twenty-four hours, from each of them, 

 with the same accuracy. The result showed, that in Candidate Hoff 

 mann the secretion of urine was considerably augmented by the very 

 large quantity of liquid which he had swallowed in the cause of science, 

 but that it was far less than that passed in the same time by the sick 

 men. Hoffmann passed from five thousand to six thousand cubic 

 centimetres (five to six quarts), while the patients passed from 

 seven thousand to ten thousand. It is possible that the presence of 

 sugar in the blood may increase the power of filtration through the 

 glomeruli of the Malpighian capsules, thereby augmenting the amount 

 of urine secreted. However, this hypothetical explanation of the 

 polyuria of diabetes is superfluous, since it is fully accounted for by 

 Vbgel, in his classical work upon this disease, as follows : " What- 

 soever may be the source of the sugar contained in the blood in dia- 

 betes, the necessary consequence of its presence is, that the saccharine 

 serum of the blood greedily attracts to itself, by endosmosis, all the 

 liquids from the parenchyma, and all the water of the food and drink 

 which enters the alimentary canal. The more the blood attracts 

 water, so much the more does it increase in volume, and augment the 

 intravascular pressure. The increase of pressure in the glomeruli of 

 the Malpighian capsules of the kidneys then produces polyuria." 



The high specific gravity of diabetic urine, which in mild cases 



