Improvements relating to microscope counting chambers for eosinophil and basophil counting

摘要

739,662. Microscope slides. BOGHRATI, N. March 15, 1954, No. 7532/54. Class 97 (1). A counting chamber for determining by microscopic examination the number of different leucocytes in the blood consists of a transparent plate having in the middle of one side a plane surface for supporting a cover glass and, in said surface, a flat-bottomed recess serving as the chamber, the bottom of the chamber carrying the usual rulings and a groove surrounding the recess to receive excess liquid when the cover glass is applied. Fig. 1 shows the plate in plan and Fig. 2 in section. The plate comprises plane end portions 3 and a raised central portion having a plane top surface and containing grooves 6 and a recess 4 forming the counting chamber. Holes 11 are provided for the mounting of springs holding a cover glass in position on the central surface to provide a completely enclosed chamber over the recess 4. Excess of the blood solution on filling the chamber flows into the channels 6. The volume of the chamber may be 10 cubic millimetres to facilitate calculation of the number of leucocytes per cubic millimetre of the blood.