Signedthermometer marked: ARTHUR H. THOMAS CO, PHILA, PA.
on thermometer: CORNING NORMAL GLASS
Inscribedon thermometer: BECKMAN THERMOMETER 1/100°C
scale marked on front: 'A.B.' [and] No. G.B.
glass etched: B.S. No 22112
FunctionThis is a thermometer that the user can fill with different amounts of mercury to use at different temperature ranges. It is extremely precise but because of this it has a narrow range of 5.5 degrees Celsius. To set it up for use, the thermometer would be placed in contact with a substance a few degrees above the upper required limit of temperature, and enough mercury would then be poured in so that the stem filled up to the s-bend. That way, the thermometer would have a range up to that temperature.