While photographing snowflakes was his passion, Bentley also turned his interest to examining and sizing raindrops for seven summers from 1898 to 1904. From that work, he gave us early insights into raindrops and their size distribution in storms. After some experimentation, he developed a simple yet effective apparatus for gathering raindrops: a shallow pan of wheat flour. At first, he simply photographed the imprints made by the falling rain in the flour. Then in 1898, he made a serendipitous finding. In his journal, he wrote: “In the bottom of each raindrop impression in the flour there could always be found a roundish granule of dough nearly exact size of raindrop. After experimenting with artificial raindrops I could measure [its] diameter before falling into the flour, and thus tell if the dough granule corresponded in size with the measured raindrop.”