THE KIDNEYS SECRETION OF URINE. 519 



kind, arises out of its possession of a power of retarding the metamorphosis 

 of the tissues; since \ve find that men, when supplied with this article, can 

 far better sustain being put upon a short allowance of food, than when des- 

 titute of it. 



418. Of the substances that accelerate the metamorphosis of the tissues, 

 and thus augment the solids of the urine, the Alkalies and their carbonates 

 and Chloride of Sodium are those whose action is best known ; these (with 

 such of their salts as are formed by acids which are decomposed in the blood 

 into the carbonic, such as the acetates, tartrates, and citrates) have a solvent 

 action on the albuminous compounds generally, and tend to break up these 

 compounds into simpler forms of combination. Hence it seems likely that 

 their presence in the Blood in increased amount, will tend to hasten the 

 retrograde metamorphosis of the tissues; their chemical force being ex- 

 erted, not merely upon those which are already in a state of disintegration, 

 but also upon those which, being disposed to degenerate, cannot exercise 

 that resisting power which they possess when in a state of complete vital 

 activity. 1 The operation of Liquor Potassse in health, in acute rheumatism, 

 and in chronic diseases, has been carefully studied by Dr. Parkes; 2 and he 

 has given satisfactory evidence that it causes an increase in the solids of the 

 urine generally, but especially in the urea and in the amount of the sulphuric 

 and phosphoric acids ; thus clearly showing that it hastens the metamorphosis 

 of some of the albuminous structures of the body. Similar results were ob- 

 tained by Dr. Golding Bird, 3 from the employment of acetate of potash. 

 It does not appear, however, that the excretion of the urinary solids is aug- 

 mented by those "diuretic" medicines, which cause a larger amount of liquid 

 to be passed off through the Kidneys, merely by determining an increased 

 flow of blood to them. On the contrary, it would seem as if, by producing 

 congestion and irritation, they sometimes interfere with the normal process 

 of secretion; so that the quantity of solid constituents is actually decreased, 

 notwithstanding the large augmentation in the watery part of the urine. 4 

 This very important fact has been demonstrated by Prof. Krahmer, 5 who 

 gives the following as the result of his observations upon the amounts ex- 

 creted in 24 hours, after the administration of diuretics to persons in health: 



Total solids. Organic Inorganic 



Medicine given. iu Urine. Compounds. Compounds. 



None, 2.40 oz. 1.28 oz. 1.13 oz. 



Juniper, 2.12 " 0.94 " 1 18 " 



Venice Turpentine, . . . 1.94 " 1.11 " 083 " 



Squill, 2.25 " 1 04 " 1 21 " 



Digitalis, 2.45 " 1.28 " 1.17 " 



Guaiacum, 2.43 " 1.38 " 1 05 " 



Culchicum, 2.32 " 1.36 " 0.9(3 " 



It seems highly probable that the " critical evacuations " of urine, as of 

 sweat, or fecal matter, on which the older physicians were accustomed to lay 

 great stress, are really charged .with noxious substances, of which the blood 

 is thus depurated ; and that great benefit would frequently arise in practice 

 from the use of the "alterative "diuretics," as suggested by Dr. G. Bird, 

 where (as in chronic rheumatism, gout, etc.) there is reason to believe that a 



1 See Voit, On the Action of Common Salt, etc., Munich, 1860. 



2 Brit, and For. Med.-Chir Review, vols. xi, xiii, xiv. 



3 See his Lectures on the Influence of Researches in Organic Chemistry on Thera- 

 peutics, in Medical Gazette, 1848, vol. xlii, p. 230. 



4 In the case of Digitalis Dr. Brunton found there was a cnnsidcradlc absolute, 

 though not relative, increase in the amount of urea eliminated. See Bruntun, On 

 Digitalis, p. 42, 1868. 



* Heller's Archiv, Dec. 1847. 



