On animal chemistry in its application to stomach and renal diseases / by H. Bence Jones.

Date:
1850
Catalogue details

Licence: Public Domain Mark

Credit: On animal chemistry in its application to stomach and renal diseases / by H. Bence Jones. Source: Wellcome Collection.

Provider: This material has been provided by the Royal College of Physicians of Edinburgh. The original may be consulted at the Royal College of Physicians of Edinburgh.

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    question. It can tell whether the urine is ammoniacal, or alkaline from fixed alkali, or contains little or much acid, but it cannot tell whether the acidity is more than it should be. Simple inspection of the urine is able to solve this question, and that better than any other mode whatever. There cannot be an excess of free acid in the urine without the uric acid being set free, though this often requires many hours to crystallize out. If, then, you wish to know if the urine is too acid, you must leave the phial at rest for twenty- four, and sometimes ninety-six hours ; and if there be too much acid, red crystals of uric acid will be very distinctly seen adhering to its sides, or deposited. The microscope may tell you quicker, but it will not tell you more surely, than the naked eye. Whatever the degree of reddening of the litmus, or the amount of urate-of-ammonia sediment, you cannot with truth speak positively of an excess of acid being present, unless you see uric-acid crystals ; and it is only when free acid is present in the urine, that alkaline re- medies are absolutely necessary. Litmus-paper, then, tells if the urine is acid or alkaline. Uric-acid crystals tell if it is too acid ; their absence indi- cates that alkaline remedies are not absolutely necessary. If the urine is alkaline, heat applied to the litmus-paper will generally tell whether it be from fixed alkali or ammonia. If the former, mineral acids and tonics have the best possible effect; if the latter, inflammation of the mucous membrane is the most probable cause of the change of the urea into carbonate of ammonia. The microscopic examination of the sediment serves to confirm all these deductions. In the last case, pus-globules and prisms of phosphate of ammonia and magnesia are seen ; in the former case, granules of phosphate of lime, more rarely crystalline phosphate of lime, and frequently oxalate- of-lime octahedra.