the bentley snow crystal collection jean m. phillips, librarian space science & engineering...
TRANSCRIPT
The Bentley Snow Crystal Collection
Jean M. Phillips, LibrarianSpace Science & Engineering CenterUniversity of Wisconsin-MadisonNovember 2005
Discussion outline
Wilson A. Bentley: History and work Professor Benjamin Snow What is snow? Snow crystal pictures (movie) Grow your own snow crystals Snow crystal classification Bentley Collection Other snow resources
Wilson Alwyn Bentley, 1865-1931
First photomicrograph of an ice crystal on 15 January 1885
Snowflakes are composed of many ice crystals that collide and stick together as they fall – Bentley, with persistence, was able to find and isolate individual ice crystals
How Bentley took pictures: Adapted a microscope to a bellows camera
What is a glass lantern slide? How many pictures did Bentley take and
why did he take so many?
Bentley’s reputation and scientific contributions
Early work ignored by scientists 1924, awarded first research grant by AMS Earliest attempts to classify crystals as a
function of temperature Observations documented: temperature, cloud
type and height (where possible), surface winds and direction, cloud movement, etc.
First in U.S. to study raindrops and their sizes; insight into the origins of rain
Bentley with camera
Professor Benjamin Snow Taught physics at UW-Madison until 1925 with great
enthusiasm: “no student should graduate from the College of Letters & Science without taking it [physics]”
He learned about Bentley’s “snow pictures” long before 1920
Professor Snow gave “snowflake” lectures about two times per year to standing-room-only crowds
Snow’s legacy: “two men on campus to whom we tipped our hats…one was Van Hise (president), the other was Snow”
Later, ~1300 slides were given to meteorology department and then, to the library in 2001
What is snow?
Snow is precipitation that freezes and collects in clouds
When released, the crystals may join together or grow depending on the temperature of the atmosphere
All snow crystals start as hexagons (each type of crystal has its own distinct shape)
Why is it important to study snow crystals?
Environmental Temperature and Crystal Formation
°C °F Crystal Form
0 to -4 32 to 25 Thin plates
-4 to -10 25 to 14 Columns
-10 to -12 14 to 10 Plates
-12 to -16 10 to 3 Dendrites
-16 to -22 3 to -8 Plates
-22 to -50 -8 to -58 Hollow columns
[From The Why Files: Know Snow]
Snow crystal pictures
Grow your own crystals
http://whyfiles.org/123snow/2.html
Snow Crystal Classification
http://library.ssec.wisc.edu/bentley/about.html#classification
http://library.ssec.wisc.edu/bentley
Snow Web Sites All about snow (NSIDC):
http://www-nsidc.colorado.edu/snow/index.html Snow crystals (Kenneth Libbrecht, CALTECH):
http://www.its.caltech.edu/%7eatomic/snowcrystals/ Secrets of crystal growth (LLNL):
http://www.llnl.gov/str/DeYoreo.html Wilson A. Bentley (Jericho Historical Society):
http://snowflakebentley.com/ Know Snow (The WhyFiles):
http://whyfiles.org/123snow/index.html
Snow Books Bentley, W.A. and Humphreys, W.J. Snow crystals. Dover
Publications, 1962. (Includes many pictures of snow crystals) Blanchard, Duncan C. The Snowflake man: A biography of
Wilson A. Bentley. McDonald & Woodward, 1998. LaChapelle, Edward R. Field guide to snow crystals. University
of Washington Press, 1969. Libbrecht, Kenneth. The Snowflake: Winter’s secret beauty.
Voyageur Press, 2003. Martin, Macqueline Briggs. Snowflake Bentley. Houghton
Mifflin, 1998. (Children’s book)
Major scientific publications of Bentley: http://library.ssec.wisc.edu/bentley/about.html#history