Historical information
See http://ubshwiki.ballarat.edu.au/index.php/Beckman_Instruments_Inc.
Physical description
Laminex covered timber box with handle, hinged top and front opening door. The box holds a pH Meter Model GS, with a number of dials and switches.
the pH Meter measured the acidity or alkalinity of almost any solution, combining electronics and chemistry to create a product that was the first of its kind.(http://www.fundinguniverse.com/company-histories/beckman-instruments-inc-hist )
On the inside cover of the box is a printed page of instructions for use.