the bentley snow crystal collection jean m. phillips, librarian space science & engineering...

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