The Art and Science of the Snowflake: From Wilson Bentley to the GE Research Lab
By Mirror Magazine
Friday, February 4, 2011
Snow is something you either love or hate. It can make the world look clean and beautiful or it can make our driving difficult and dangerous. Even skiers who love to make use of it for their fun hate it on their driveways. There are many ways to enjoy it, from the ski slopes to observing the beauty of a single flake.
The recognition of the form and beauty of the snowflake first came from a former neighbor over in Vermont, where he lived all his life on a farm near Jericho next to “Bolton Mountain.” Starting in the last century, he became known as “the Snowflake Man.” Wilson A. Bentley (1865-1931) spent his entire life studying and photographing the flakes that came down from the winter clouds.
Before the age of 14, Bentley learned how to draw and later, to photograph the complicated snow crystals. He used his mother’s old microscope out in their cold barn. He produced the world’s first photomicrographs of snow crystals. He continued to do this through his whole life right up to his death at age 66. During this time, he accumulated 5,381 photographs of snow crystals that are now admired and recognized for their quality and beauty all over the world. It was not long into his activity that he originated the well known saying ”No two snowflakes are alike.” This still stands. For a long time, his work was ignored, even though he sold hundreds of his snow crystal photographs for just five cents.
Obviously he never made much money from them, but they finally brought him much fame and recognition. He was invited to give lectures at universities and before scientific societies. He wrote numerous papers in science publications, including a book entitled “Snow Crystals,” which is still used as a reference. His interest in snow crystals – and their foretelling of the weather conditions that caused them – gave him an interest in all weather phenomena and was the cause of much correspondence with the National Weather Bureau. For those interested in knowing more about this remarkable man, his biography, “The Snowflake Man,” has been written by Duncan C. Blanchard, who worked in the next phase of the study of our winter precipitation.
Many years after the Snowflake Man had passed on, his work was used by and, indeed, stimulated another important study of snow events. This originated in one of the world’s most prestigious scientific research organizations, just south of the Lake George region. In the General Electric Research Laboratory in Schenectady, Dr. Vincent Schaefer and a group of scientists learned how to make the snow Wilson Bentley spent his life drawing, photographing and studying.
The first method of manmade snow was to “seed” the water droplets of a bank of supercooled saturated clouds. This is done from an airplane with small pieces of dry ice (solid carbon dioxide). This further cooled the supercooled water droplets of the cloud to below the critical temperature so they froze into snow crystals that grew as they fell through the cloud, ending up as a snow fall.
The next method, developed by Dr. Bernard Vonnegut in the same lab group, was to pass silver iodide vapor into the supersaturated cloud. Since silver iodide has a crystalline structure very similar to that of water, it acted as a nucleus around which a snow crystal grew. The silver iodide vapor may be blown into the clouds by the wind even from locations on the ground. This started the period of man-made rain producing. It became so widespread that the GE Research Lab had to get out of the “cloud physics” work because of the corporate liability potential. Dr. Schaefer and most of the group left and started the Atmospheric Sciences Research Center at the University of Albany of the State University of New York. It is still operating today.