This example of Met office aneroid barometers used in various weather stations around the UK.

Barometers measure atmospheric pressure also known as air pressure and often are an indicator of what the weather might do.

You lineup the two needle, it falls for worsening weather or rises for better weather.

The last two numbers representing the year of manufacture the Mo logo, which indicates it was made specifically for the meteorological office by different makers.

The first pocket barometers were produced in the early 1860s.

 The development of pocket barometers progressed rapidly after the 1870s.

  The Negretti and Zambra company, which was active from the 1850s to around 1935, produced a pocket barometer around 1867.

 Pocket Barometers, Victorian men typically wore them in their waistcoat pockets on a chain.

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