This is a rare working recording rain guage known as 'The Wilson' circa 1912. As with many outside weather instruments, such as these and anemometers were often left outside and simply corroded away, hence surviving examples are now quite rare. This particular style is sought after as it has a crisp white enamel dial, clesrly showing all the scales unlike other models with a silvered metal dial. Note, the large outer scale records up to 2 inches of rain with the smaller inner scale inner will record up to 25 inches before re-starting at zero. Another feature is there are circular viewing windows on either side, presumably to check if the tipping bucket movement is not hindered by nesting small rodents! Finished in zinc, the outer base is in very good condition for its great age while the lift off lid has been strengthened at some stage.
These rain recorders were very popular with enthusiasts in the early 20th century - see extract from the 1926 trade catalogue by Taylor Instruments of New York, who imported these from Short & Mason of London.