FOREIGN SUBSTANCES IN THE URINE.
Medicines, and substances taken for food, are occasionally found in the urine. Some of these, however, undergo changes in the organ ism before they are excreted by the kidneys.
Simon has classified these bodies ; and I shall here enumerate them according to his arrangement.
Inorganic non-metallic bodies. — Iodine, bromine, chlorine, sulphur *, iodide of potas sium, alkaline borates, silicates, chlorates, and carbonates, chloride of barium, ferridcyanide of potassium, sulphocyanide of potassium. The ferridcyanide was converted, however, into the ferrocyanide in the system.
Metallic substances. — Arsenic, antimony, iron, nickel, •gold, silver, tin, lead, bismuth, copper, and manganese. I have sought in vain for mercury in the urine. Lehmann and L'Heritier have also failed to find it where it has been largely exhibited. Several chemists, however, declare they have detected it.
Inorganic acids. — Nitrict, hydrochloric, and sulphuric.
Organic acids. — Oxalic, citric, malic, tar taric, succinic, gallic, and acetic.
Pereira has succeeded in detecting meconic acid in the urine of animals poisoned by opium. Vegetable bases. —Quina, morphia.
Indifferent organic substances. — Colouring matters of indigo, gamboge, rhubarb, red root, madder, logwood, mulberries, black cherries ; odorous principles of valerian, assaketida, garlic, castoreum, saffron, turpen tine.
Liebig and Wiihler both state that alcohol cannot be detected in the urine. Percy, how ever, has proved that it can. Dr. Wright has corroborated Percy's experiments, and ob tained alcohol by the same plan of analysis.
Lehmann and others sought unsuccessfully for the following substances in the urine : viz., salicin, phloridzin, caffein, theobromin, as paragin, and amygdalin. These substances probably undergo changes in the organism.
Lehmann has shown that salicin becomes converted into salicylous acid ; this was taken up by ether with the oxide of omichmyle. The addition of nitrate of iron produced the fine violet colour characteristic of salicylous acid. Hippuric acid and oxalate of lime were also produced.
Phloridzin is converted into oxalic and hippuric acids during its passage through the organism, according to Lehmann.
For the Bibliography reference is made to the works of Berzelius, Prout, Simon, Liebig, Dumas, Lehmann, on Animal Chemistry, and to those quoted in the foot notes.
(G. Owen Rees.)