Einstein, Albert.

stating that the confirmation of the prediction of the theory is really a relief for him ("...Die Bestätigung der Theorie ist fuer mich wirklich eine Befriedigung...") and thanking him for his congratulations; in another part of the letter Einstein discusses a banking matter and informs him of his travel plans, 1 page, oblong 8vo (13.9 x 9cm), on a postcard, autograph address panel, [Berlin,]17 October 1919, corners creased, a few small marks

Condition is described in the main body of the cataloguing where appropriate.
"In response to your inquiry, we are pleased to provide you with a general report of the condition of the property described above. Since we are not professional conservators or restorers, we urge you to consult with a restorer or conservator of your choice who will be better able to provide a detailed, professional report. Prospective buyers should inspect each lot to satisfy themselves as to condition and must understand that any statement made by Sotheby's is merely a subjective, qualified opinion. Prospective buyers should also refer to any Important Notices regarding this sale, which are printed in the Sale Catalogue.
NOTWITHSTANDING THIS REPORT OR ANY DISCUSSIONS CONCERNING A LOT, ALL LOTS ARE OFFERED AND SOLD AS IS" IN ACCORDANCE WITH THE CONDITIONS OF BUSINESS PRINTED IN THE SALE CATALOGUE."

A sensational letter containing Einstein's reaction to the event which made him world famous, the stunning first experimental proof of his theory. 

A prediction arising from Einstein's general theory of relativity (1915) was the curvature of light in a gravitational field, a hypothesis which it was theoretically possible to test by observing light from stars during an eclipse. In May 1919, a British team of scientists led by Arthur Eddington, Plumian Professor of Astronomy at Cambridge, appeared to confirm Einstein's prediction as a result of studying a solar eclipse in Sobral, northern Brazil and on the west African island of Principe. The official positive confirmation at a meeting of the Royal Society and the Royal Astronomical Society on 6 November 1919 resulted in the physicist's instant worldwide fame. Two years later Einstein was awarded the Nobel Prize for Physics.