Ph metre

Why is the word 'metre' used as the heading in this article? It should be 'meter'!  'Metre' is a unit of length, similar to a yard.  A 'Meter' is an instrument used to measure a quantity, as in 'thermometer' (measures temperature), 'voltmeter' (measures volts, surprise surprise) and 'speedometer'. It's bad enough seeing these words incorrectly used in low-quality newspapers, but to see it being done within a much-respected scientific discussion group is just too much...

Happy New Year everybody!

P.S. 'Year' is a unit of time, sometimes pronounced 'Yer', as in 'Woss yer name?'

Why is the word 'metre' used as the heading in this article? It should be 'meter'!  'Metre' is a unit of length, similar to a yard.  A 'Meter' is an instrument used to measure a quantity, as in 'thermometer' (measures temperature), 'voltmeter' (measures volts, surprise surprise) and 'speedometer'. It's bad enough seeing these words incorrectly used in low-quality newspapers, but to see it being done within a much-respected scientific discussion group is just too much...

Happy New Year everybody!

P.S. 'Year' is a unit of time, sometimes pronounced 'Yer', as in 'Woss yer name?'

It's french. Thermometer = thermomètre, voltmeter = voltmètre and pH meter = pH-mètre.

Wikipédia

And here in the US... meter is also how we spell the unit of length.   It's just our rebellious nature.  
I've gotten the colour/color thing down, but I still haven't figured out the grey/gray thing.  And I've jokingly said aluminum wrong for so many years that I can't say it right to save my soul.  Or it that sole...

kmikemoo said:

And I've jokingly said aluminum wrong for so many years that I can't say it right to save my soul.

 kmikemoo  I recall lexicographer Susie Dent discussing this one on several occasions.

At one time British English also used 'aluminum' in order to match the ending of the likes of 'platinum' but then later on changed it to 'aluminium' to match the endings of  the likes of 'magnesium' and 'potassium'.

kmikemoo said:

I've gotten the colour/color thing down

Similar sort of story there with both forms being in common use up until around the time Samuel Johnson attempted to standardise spelling. Then Noah Webster came along and attempted to simplify spelling by removing superfluous letters...