How to Design a Rain Gauge Using a Jar & a Ruler
- 1). Select a clear glass jar that has an opening that is as wide as the rest of the jar. Many commercial food jars will have openings as wide as the body of the jar and will make excellent rain gauge basins once the labels are removed. Labels can be removed by soaking the jar in water, then scrubbing the label with an abrasive sponge.
- 2). Set the jar on a level surface. Place the clear plastic ruler against the side of the jar so that the zero marker of the ruler is resting on the level surface. Wrap the jar with the clear plastic adhesive tape to secure the ruler to the outside surface.
- 3). Place the rain gauge outside in an area where there are no obstructions that may block any potential rainfall. Rainfall will accumulate in the jar and the amount can be determined by reading the measurement on the ruler to determine the depth of the water in the jar.
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