On Monday, 26 December 2016 16:32:25 UTC, Bernard Burton wrote:
"Vidcapper" wrote in message
...
On 26/12/2016 11:31, Desperate Dan wrote:

Met office mercury in glass thermometers have a five year calibration
period.


Why just 5 years - surely the only thing that can go wrong is if you drop
them?

--

Paul Hyett, Cheltenham

Not so. The glass can creep due to changes in the glass of the bulb, which contracts slowly over time.


So he can't use his as a rule.