QUESTION: I don't understand if it rains one inch why it would show 4 inches. Can you please explain this? ANSWER: The rain gauge has a gathering funnel at the top that gathers the rain from more than a 'one square inch' area. A one inch rainfall would gather one inch of water if the rain gauge didn't have the funnel. If the funnel was the size that would cover 2 square inches, one inch of rainfall would show as 2 inches in the rain gauge. If the funnel was the size that would cover 3 square inches, one inch of rainfall would show as 3 inches in the rain gauge. The funnel is calibrated to gather the water from a large enough area to raise the rain gauge more than 4 for each inch of rain that actually falls. The gauge is made like this so that it is easier to read, and so that the amount of rainfall can be determined from a distance.
Overall Rating: 4/5
Cleaning rain gauge
Like everything about this rain gauge. Away on holiday, rain sat in gauge for 14 days and algae collected/dried in bottom. Would like to know how to clean dried algae. Does the bottom "button" unscrew? My bottle washer is not long enough to reach bottom. Bleach did not loosen the dried scum.