Estimated Date: 1925
Name: American Standard Haemacytometer
Manufacturer: Arthur H. Thomas Company
Description: 7“x 4“x 0.75” black leatherette case with above embossing plus with Levy-Hausser Counting Chamber. Contains counting chamber pat Jan 8, 1924, white cell and red cell pipette, mounting clips and rubber tubing.
Reference 1: 263