Comprising a wooden base board 1100x115mm with one meter scale divided in millimeters and figured at every centimeter fixed along the front edge and complete with following accessories, two white faced object and receiving screen, one plane mirrог 150х100mm, 4 lens holder V shaped, one needle mounted vertically in a short wooden rod in the centre of a wooden base.

Same as above but 1.5 meter long.

Of clear perspex, all faces nicely polished 80mm dia and 20mm thick approximately.