Direct halometer set

Equipment to measure the average diameter of red cells in micromillimetres. Consists of stainless steel halometer; stainless steel tube of glass slides; a stainless steel tube of unknown contents (does not open) and pack of surgeons’ needles straight and triangular type size 6. Patent No: 393590. Housed in a wooden box size H:7 x L:16 x W:12cms)