$5,000
Typed letter signed ("A. Einstein") to Mr. Hans Cassel, February 5, 1937, in ink on embossed stationary paper measuring 8 1/2" x 11" (one page). Einstein writing "Now it is clear to me where your mistake in your thoughts lies." (Cond: paper shows creases from folding, age toning, nicks to edges, paperclip transfer marks) Provenance: Family of Dr. Hans Cassel, Boca Raton, FL (8000/10000) German to English Translation: The February 5, 1937 Dear Mr. Cassel: Now it is clear to me where your mistake in your thoughts lies. You say in your letter: “but because p’ must reduce by the reduction of the drop with the occurring area enlargement” So you see a virtual change in the systems, by which the drop count changes and by which the drop equality stays the same (the equality of the radius of the drop from each other). That is not the issue at all. The drop radius is not dependent on one another. In truth we are dealing with the evaporation-stability from a single drop. To contemplate is the virtual change in the change of r from a single drop. By such virtual change p’ changes less with r, the larger the overall volume of the vapor. So you have to set: dp’/dr = 0 As requirement for the equilibrium of the drop, you get the never reachable formula: 2g/r
Auctioneer:
Auction Gallery of the Palm Beaches
Date:
2011-06-27
