A manual of clinical medicine and physical diagnosis / by Thomas Hawkes Tanner.

  • Tanner, Thomas Hawkes, 1824-1871.
Date:
1876
Catalogue details

Licence: Public Domain Mark

Credit: A manual of clinical medicine and physical diagnosis / by Thomas Hawkes Tanner. Source: Wellcome Collection.

    303/346 (page 285)
    URIC ACID m SERUM OP BLOOD. 2m ozone: and to this is due its reaction. Ether which con- tained an ozonide would blue guaiacum resin, whether blood were present or not. The test-solution is the ethe- real solution of peroxide of hydrogen, which is an antozo- nide. The so-called ozonised essential oils, as oil of turpen- tine, lavender, &c., really contain antozone; and to this may be ascribed their use in detecting blood ; for at first oil of turpentine was used, instead of the peroxide of hy- drogen ; but the results were unsatisfactory. If the blood-stain be on dark cloth, the test, as above described, may be used; but then an impression must be taken ofE on white blotting-paper, otherwise the blue colour will not be visible. The exact nature of the chemical change that takes pla.ce is doubtful; but the test is so simple and easy of application, and, above all, so very delicate, that it is likely to become very generally used. This test fails, as other tests have failed before, to show whether the blood stain is human or not. The microscope will point out whether a corpuscle comes from a fish, a reptile, or mammal.^* 33r. Crarrod's Plan of ascertainingr the Presence of an Abnormal Quantity of Uric Acid in tbe Serum of tbe Blood.—Takefrom one to two fluid drachms of the serum of the blood, and put it into a flattened glass dish or capsule ; to this add the strong acetic acid of the London Pharma- copoeia, in the proportion of about six minims to each fluid drachm of the serum. A few bubbles of gas are generally evolved at first; but when the fluids are well mixed, two or three fine threads, or one or two ultimate fibres from a piece of unwashed huckaback, are to be in- troduced. The glass is then to be put aside in a mode- rately warm place—as on the mantelpiece in a room of ordinary temperature—until the serum is quite set and almost dry, the time required varying from eighteen to forty-eight hours. If the cotton fibres be then removed and examined microscopically with an inch object-glass, they will be found covered with crystals of uric acid, if this agent be present in abnormal quantity in the serum. The crystals form on the thread, somewhat like the crystals of sugar-candy on string. See plate, fig. 2. * British Medical Journal^ Sept. 5, 1868.