On the chemistry and therapeutics of uric acid gravel and gout : being the Croonian lectures for 1892 delivered before the Royal College of Physicians of London / with additions by Sir William Roberts.

  • Roberts, William, Sir, 1830-1899.
Date:
1892
Catalogue details

Licence: Public Domain Mark

Credit: On the chemistry and therapeutics of uric acid gravel and gout : being the Croonian lectures for 1892 delivered before the Royal College of Physicians of London / with additions by Sir William Roberts. Source: Wellcome Collection.

Provider: This material has been provided by the Francis A. Countway Library of Medicine, through the Medical Heritage Library. The original may be consulted at the Francis A. Countway Library of Medicine, Harvard Medical School.

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    It is liable, after being voided, to come into contact with the water used for cleansing the cages in which the creatures are confined; and water, as we have seen, speedily disintegrates it. Again, if the substance be not at once completely dried on the hot-water bath, it under- goes bacterial decomposition, and is thereby transformed into bi-urate of ammonia. This is the condition in which ' serpents' urine' as supplied by the dealers is generally found. But even if both these sources of change are avoided by taking proper precautions, there is yet another which no care can obviate. The large serpents void their urine at long intervals, varying from a week or ten days to six or seven weeks. During this long sojourn in the urinary passages, the secretion undergoes slow changes which affect its chemical constitution. I have always found serpents' urine, when examined in the fresh state, to have a sharply acid reaction. Under these conditions a certain amount of decomposition of the urates, with liberation of free uric acid, is inevitable.1 Accordingly, when samples of serpents' urine were subjected to water analysis, however carefully the samples had been collected and preserved, the amount of uric acid separated by water was always found to be considerably in excess of that which went into solution as bi-urate. The invari- able presence in the secretion of free uric acid was thus demonstrated. The subjoined table exhibits some of the results obtained by water analysis of freshly gathered specimens of the urinary excrement of the boa :— 1 Herein, no doubt, lies the remarkable difference in the results of water analysis of the urine of the fowl and that of the boa. The fowl discharges its urine many times a day.' There is no detention of it in the urinary passages, and therefore no time for the occurrence of appre- ciable secondary changes.