A letter dated December 15, 1904 from Bentley asking the Smithsonian to preserve and house his snowflake photographs. (Click link or photo to see digitized transcript)
Letter dated December 26, 1904 from Bentley thanking the Smithsonian for offering to house and preserve his photos. (Click link or photo to see digitized transcript)
A hand written lecture by William Bentley on snow crystals from November 1905.
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