Clinical pathology of the blood : a treatise on the general principles and special applications of hematology / by James Ewing.
- Ewing, James
- Date:
- 1904
Licence: In copyright
Credit: Clinical pathology of the blood : a treatise on the general principles and special applications of hematology / by James Ewing. 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.
49/570 page 45
![slowly through the paper, so as to give as even a stain as possible. Immediately after the stain has lost its lustre and before drying or changing color by exposure the percentage of Hb is determined by matching with one of the colored areas in the scale. It is unneces- sary to mention the serious sources of error in this method, which hardly estimates but rather assists one to judge the percentage of lib. 3. Fleischl's Hemoglobinometer. (a) Apparatus. This appara- tus consists of a metal stand with plate, and plaster mirror [8] which casts diffused light through a circular opening in the plate. Beneath the plate, by means of a rack and wheel (T), slides a colored glass wedge fixed in a graduated frame (P). The glass wedge and gradu- ated scale are arranged so as to indicate the percentage of Hb corre- sponding to the different portions of the wedge. In the circular opening of the plate fits a cylindrical metallic cell {G), with glass Fig. 14. Fleischl's hemoglobinometer. bottom and metal partition, one compartment of which lies directly over the glass wedge. The other compartment (a) being filled with diluted blood, one is able to make a close comparison of the color of the dissolved blood with that of the glass wedge. The blood is measured by an automatic capillary pipette, while a slowly running dropper is provided with which to add distilled water. On the handle of each pipette is stamped a number, indicating the cubic content of the tube. On the stand of each instrument is also a number showing the capacity of the tubes with which it can be used. (6) Procedure. One should first see that the automatic pipette is in working order, by blowing it out several times with water until it fills instantly and completely, after which it must be thoroughly dried. A drop of blood having been expressed under very strict precautions against pressure, one end of the pipette is lightly touched](https://iiif.wellcomecollection.org/image/b21503886_0049.jp2/full/800%2C/0/default.jpg)
