2. Oxalic acid has, if not its sole, its chief source in the azotized constituents of the blood and food; everything, therefore, which retards the metamorphosis of these constituents occasions oxaluria.
3. Such a retardation of the metamorphosis of the azotized con stituents of the blood and food may be determined by the following causes : a. Abuse of azotized articles of food (direct retardation).
b. Abuse of saccharine and starchy articles of food (indirect retardation).
c. Insufficiency of the red blood corpuscles and eventually dimin ished oxidation.
d. Insufficient enjoyment of pure, fresh air.
e. Organic lesions which in any way impede respiration and the circulation of the blood.
f. Conditions of the nervous system which bear a character of depression, whether these arise primarily from mental derangement or from pathological states of the blood.
4. Excess of alkaline bases in the blood, as observa tions tend to show, plays an important part among the etiological conditions of oxaluria; and it is not improbable that an increased production of lactic and butyric acids in the digestive canal, con sequent thereupon, impedes the development of the red blood cor puscles, and thereby generates that chlorotic state which so often occasions and accompanies oxaluria.
5. Catarrhal conditions of the intestinal mucous membrane, in case they are accompanied by oxaluria, have at most only an indirect causal relationship. They may determine oxaluria by causing de ranged digestion but cannot be considered as the proximate cause.
It must be confessed that many of the patients who are supposed to be suffering from oxalic diathesis or oxaluria, have a well-marked history of sexual excess, that spermatozoa are not infrequently found in decided quantities in the urine accompanying the oxalate of lime, and that many of the symptoms which are supposed to be the direct result of the excess of oxalate of lime may be accounted for by the debilitating loss of seminal fluid. Moreover, many of the vague pains and depressed feelings can be accounted for by the renal resent ment of fixed oxalate concretion or by the passage of the sharp irritating crystals along the sensitive urinary passages, arousing the reflex excitability of the prostatic urethra and its innumerable nerv ous connections.