296 EXCRETION OF SUPERFLUOUS NON-AZOTXZED NUTRIMENT. 
349. Hence the radical cure of these diseases, in most 
persons who have a sufficiently vigorous constitution and firm 
resolution to adopt it, is abstinence from all azotized nutri¬ 
ment—whether contained in animal flesh, bread, or other 
articles of vegetable diet,—save such as is required to supply 
the wants of the system. If such abstinence he carried too 
far, however, it will produce injurious instead of beneficial 
results, weakening the fabric, and impairing the digestive 
powers; and if food be employed of a kind which is liable to 
produce lactic acid (the acid that appears in milk, when it turns 
sour), much disorder may still remain, which must be avoided by 
using the kind of diet that is least liable to undergo this change. 
350. Again, if more non-azotized food is taken into the 
system than can be got rid of by Eespiration, it must either 
be deposited as fat, or it must be separated from the blood, 
and carried-off by the excretion of the Liver. But if too 
much work be thrown upon this organ, its function becomes 
disordered, from its inability to separate from the blood all 
that it should draw-off; the injurious substances accumulate 
in the blood, therefore, producing various symptoms that are 
known under the general term of bilious ; and to get rid of 
these, it becomes necessary to administer medicines (especially 
those of a mercurial character) which shall excite the liver to 
increased secretion. The constant use of these medicines has 
a very pernicious effect upon the constitution; and careful 
attention to the regulation of the diet, and especially the 
avoidance of a superfluity of oily or farinaceous matter, will 
generally answer the same end in a much better manner. 
351. That the materials of the Biliary and Urinary excre¬ 
tions pre-exist (like the carbonic acid thrown-off by respiration) 
in the blood, in forms which, if not identical, are at any rate 
closely allied to those under which they present themselves 
in the bile and urine, has now been fully proved. The 
quantity of them present in the circulating fluid, however, is 
usually very small; for the simple and obvious reason that, 
if the excreting organs are in a state of healthy activity, these 
substances are drawn-off by them from the blood, as fast as 
they are introduced into it. But if the excretions be checked, 
they speedily accumulate in the blood, to such a degree as to 
be easily detected by the Chemist, and also to make their 
presence evident by their effects upon the animal functions* 
