Wilson A. Bentley was one of the first known photographers of snowflakes. He adapted a microscope to a bellows camera, and with this device — after much trial and error — became the first person to photograph a single snowflake in 1885. He sent 500 prints of his snowflakes to the Smithsonian in 1903. Those images are now part of the Smithsonian Institution Archives.
Bentley's book Snow Crystals, with more than 2,400 snowflake images, was published in 1931. This photomicrograph and more than 5,000 others supported the belief that no two snowflakes are alike, leading scientists to study his work and publish it in numerous scientific articles and magazines. This photo is one of 137 million artifacts, works of art and specimens in the Smithsonian's collection. It is not on public display.
And guess what? You can buy a reprint of the original Bentley book here: Snow Crystals.