This is a Canadian Type A rain gauge.  This design was the standard manual gauge used by the Meteorological Service of Canada from about 1930 to the 1970s.  It's also known as a MSC rain gauge.  It's entirely made of copper, the manufacturer is unknown.  The aperture is 3.57 inches in diameter, so that it has an opening of 10 square inches. It's about 10 inches tall and was mounted so that the opening was 12 inches above the ground.  Small amounts of rainfall could be measured in the inner cylinder with a dipstick.  Overflow from the inner cylinder goes into the middle cylinder, with a total capacity of 6 inches which was measured externally in a glass graduated cylinder.

In the 1960s the inner copper cylinder was replaced with one of plastic, as the copper cylinder was known to fail under freezing conditions.  In the 1970s it was replaced by a metric rain gauge made entirely of plastic, known as the Type B rain gauge.  It had an aperture of 4.44 inches, so that the opening was 100 square cm.  The Type B gauge opening was elevated to 15.8 inches (40 cm) above the ground.

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