38 DEGREES CENTIGRADE

(Various Makes of Thermometer, Test)

By The Rev`d Ronald S. Hatfull, C. Chem. M. Chem.A. F.R.S.C., F.R.S.H.

(Area 9.)

With reference to previous correspondence, and the note in the Newsletter No. 59 (page 12), I have now carried out a comparison of five thermometers.

These thermometers were all placed together (the probe in the case of the Maplin `Gold) in a glass beaker of water that was stood on the platform in the constant temperature bath - placing them directly in the bath gave erratic results due to the water flow.

After allowing sufficient time for the conditions to stabilise, the following steady readings were observed:-

The manufacturers statements of accuracy are:-

The maplin `Gold` thermometer is a disappointment, at the least the one that I have, but it is within specification. It is the most convenient as regards ease of reading but it is necessary to remember to correct the reading.

The surprise was the Maplin Clinical Digital Thermometer. The probe is of very small mass and it is very easy to read. When switched on it reads `L` until the temperature is displayed. To take another reading it is necessary only to switch off then on again. It is believed that a Centigrade version is available from Tandy`s.