The blood, how to examine and diagnose its diseases.

  • Coles, Alfred Charles.
Date:
1898
Catalogue details

Licence: Public Domain Mark

Credit: The blood, how to examine and diagnose its diseases. Source: Wellcome Collection.

Provider: This material has been provided by The University of Leeds Library. The original may be consulted at The University of Leeds Library.

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    3. The blood column may suddenly stop, probably either because the top of the pipette is touching the skin, or because the capillary bore of the pipette is not dry, and coagulation has taken place. The pipette now contains one part blood and 100 parts of the neutral solution, and may safely be left for some time before counting. There is no need to carry the microscope to the bedside. All that is necessary is the pipette, which can be carried in a small case a little larger than that containing a clinical thermometer, and a small bottle holding about thirty drops of the diluting fluid. In order to carry about the filled pipette Cabot suggests that a rubber band be placed longitudinally roSnd it, in order to close the ends. At first I tried to obviate any danger of escape of the contents by placing india-rubber caps on both ends, but found that this had the disadvantage of driving the fluid in the capillary bore into the bulb, making the dilution one in loi, instead of one in 100. I find now that the best method is to carefully detach the india-rubber tubino-, after the pipette is filled, without compressmg it_any pressure at this end forces a small drop of the liquid out at the point end-and then the tube is placed in its case, and kept horizontally till used. The Counting. ' The slide containing the counting chamber consists of a disc of glass, on which parallel lines are engraved, which by their intersection form 400 squares, the length of a side of each of which is of a mflhmetre. The squares are further divided by double hues mto o-roups of 16. When the coverglass is applied each cell has a depth of of ^ millimetre.