538 OF SECRETIOX. 



679. The amount of Azotized matter in the Urine, also, is greatly influenced 

 by the nature of the food ingested, whilst the constitution of the animal frame 

 remains nearly the same ; hence it appears that a large portion of it must be 

 derived from the unassimilated materials, which have been taken into the 

 blood, and which, being superfluous, are injurious. It is well known that the 

 ingestion of an over supply of azotized matter does not occasion an increased 

 production of the fibrinous or gelatinous tissues ; and it may be hence inferred 

 that, as there is no means by which the superfluous amount can be stored up 

 in the system (in the mode that non-azotized matter is stored up as Fat), it 

 must be continually eliminated from the Blood. And there can be no doubt 

 that the Kidneys are the principal channel by which this is effected ; the 

 amount of azote thrown off in a given time, in the various compounds which 

 they excrete, being equal to 10-1 Iths of the whole quantity ingested. The 

 following are the results of the most satisfactory inquiries that have yet been 

 made in regard to the influence of various kinds of Aliment upon the amount 

 of the solid matters in the Urine. These experiments were performed by Dr. 

 Lehmann, of Leipsig, upon himself. In the first series, Dr. L. adopted an 

 ordinary mixed diet ; but he took no more solid or liquid aliment than was 

 needed to appease hunger or thirst, and abstained from fermented drinks. 

 Every two hours he took exercise in the open air, but he avoided immoderate 

 exertion of every kind. The average result of the examination of the Urine 

 passed under these circumstances, for fifteen days, is given in the first line of 

 the subsequent Table. In a second series of experiments, Dr. L. lived for 

 twelve days on an exclusively Animal diet ; and for the last six of these, it 

 consisted solely of eggs. He took 32 eggs daily; which contained 189*7 

 grammes of dry albumen, and 157-48 of fatty matters; or about 228-75 

 grammes of carbon, and 30-16 of azote. The amount of Urea is- shown, in 

 the second line of the Table, to have undergone a very large increase ; and it 

 contained more than five-sixths of the- whole azote ingested. In a. third series 

 of experiments, Dr. L. lived for twelve days on a Vegetable diet ; and its effect 

 upon the solid matter of the Urine is shown in the third line of the Table. 

 For two days he took no azotized food of any kind ; and the azotized matter 

 of the Urine must therefore have been solely the result of the disintegration of 

 the tissues. It is seen to undergo a very marked diminution, under this regi- 

 men ; as is shown in the fourth line of the Table. 



Solid Matters. Urea. Uric Acid. Lactic Acid Extractive 



and Lactates. Matters. 



I. Mixed diet. . 67-82 32-498 1-183 2-257 10-480 



II. Animal diet . 87-44 53-198 1-478 2-167 5-145 



III. Vegetable diet . 59-24 22-481 1-021 2-669 16-499 



IV. Non-azotized diet 41-68 15-408 0-735 5-276 11-854 



680. The following inferences are drawn by Dr. Lehmann, from these ex- 

 periments : 1. Animal articles of diet augment the solid matters of the Urine. 

 Vegetable substances, and still more such as are deprived of azote, on the con- 

 trary, diminish it. 2. Although Azote be a product of decomposition of the 

 organism, yet its proportions in the urine depend also on the food, for we find 

 a richly-azotized diet augment considerably the quantity of Urea. In the above 

 experiments, the proportion of the Urea to the other solid matters was as 100 

 to 116 in a mixed diet; as 100 to 63 in an animal diet; as 100 to 156 in a 

 vegetable diet; and as 100 to 170 in a non-azotized diet. 3. The quantity of 

 Uric Acid depends less on the nature of the diet than on other circumstances ; 

 the differences observed in it being too slight to warrant us in ascribing them 



influenced by the respiration, is altogether left out of consideration in this sweeping 

 generalization. 



