The effect of small doses of mercury in modifying the number of the red blood corpuscles in syphilis : a study of blood-counting with the hématimètre / by E.L. Keyes.

  • Edward Lawrence Keyes
Date:
1876
Catalogue details

Licence: Public Domain Mark

Credit: The effect of small doses of mercury in modifying the number of the red blood corpuscles in syphilis : a study of blood-counting with the hématimètre / by E.L. Keyes. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    nated by the pipette; no bacteria or confervoid growths appear. It makes a homogeneous mixture with blood, and preserves the color of the corpus- cles. The latter become perfectly spherical, are slightly, but uniformly contracted (measuring 0.0006 mm.). They are perfectly preserved for a number of hours, after which some of them begin to dissolve. The above is a good fluid, and has no poisonous properties. The following is very much better, but the corrosive sublimate may make it objectionable to some.1 Take of urine, neutral or slightly alkaline, sp. gr. 1020, a sufficient quantity, filtered. Add gr. v of corrosive sublimate in powder for each ounce of urine. This will throw down dense clouds of amorphous urates, so fine that ordinary filter paper will not remove them. After standing, the urates deposit, and the clear fluid above may be easily decanted. Reduce with water to sp. gr. 1020. The result is a limpid, sparkling, acid fluid which remains clear no matter how often contaminated with the pipette, and does not seem to allow of the growth of any form of vegetation. It makes a perfect mix- ture with blood. It bleaches the red corpuscles quickly, and very slightly, but uniformly, increases their size. They retain, however, their flattened, bi-concave, disk-like shape, and do not become dissolved after standing more than twenty-four hours—beyond which time no test was made. Estimation of the accuracy of the Hematimetre.—Theoretically the method of enumerating the blood corpuscles with the instrument of Hayem and Nachet is absolutely accurate; practically it is not so. This is largely due to the minuteness and infinitely vast number of the objects counted. It would be folly to try to calculate the number of red cor- puscles in the human body, for when obtained, the figures would give no more idea to the ordinary mind of what the number really is, than would the word infinite. For example—to reduce the whole matter to figures which can be easily understood—the population of the entire earth is estimated at con- siderably under 1,500,000,000. The hematimetre shows that one cubic mm. of pure blood of a male adult in good health, holds on an average 5,000,000 red blood corpuscles. But a cubic millimetre does not furnish a very accurate idea to the mind. A centimeter is better, it is of appre- ciable size, something over the third of an inch (exactly .39371 inch). A cubic centimeter is equal to 1000 cubic millimetres, and, therefore, con- tains 5,000,000,000 red blood corpuscles—a number of distinct red cells (not to count the white corpuscles) in each cubic third of an inch of blood, more than three times greater than the population of our entire globe. This vast number of cells is probably undergoing daily and hourly 1 It is a strange coincidence that I should have found mercury the best pre- servative for blood corpuscles.
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