C4901

American Scientists

Barbara Jordan -- Chemist

Collins Cover Announcement 

American Scientists 

Melvin Calvin — Chemist

In 1937 Calvin became a member of the faculty at the University of California and in 1947 was promoted to Professor of Chemistry. Using the carbon-I4 isotope as a tracer, Melvin and two colleagues mapped the route that carbon travels through a plant during photosynthesis. Their research proved that sunlight acts on the chlorophyll in a plant to generate organic compounds rather than carbon dioxide as was previously thought. Because of his leading role in this work, Calvin was the sole recipient of the 1961 Nobel Prize for chemistry.

In 1963 he became a Professor of Molecular Biology and founded the Laboratory of Chemical Biodynamics. The esteemed scholar then became an associate director of the Berkeley Radiation Laboratory. In his final years, he did research on the use of oil-producing plants as renewable sources of energy

My hand painted cachet features a portrait of Calvin within an oval frame. As with the other covers in this set, the watercolors will complement the wonderful colors in the stamps. Added details are lab equipment at the lower left and handpainted block letters of the mini-set's title — American Scientists — to the right. The stamp and first day postmark are to the upper .left, and when complete, each of the set's four stamps will appear in a different corner. This will be an attractive series and will look good in any collection. Melvin Calvin — Chemist

Collins #C4901 at $14.00.

Still available at $14.00