D O C U M E N T S 2 5 5 , 2 5 6 J U N E 1 9 2 2 2 0 5 255. To Gustave Le Bon Berlin, 30 June 1922 Sir, Thank you for your letter of the 27th of this month.[1] It seems that your relation between mass and energy is irreconcilable with the corresponding conclusion in the theory of relativity because the latter proved that the coefficient of the equation of equivalence is equal to the square of the velocity of light. Concerning the rest of your letter, I must say it does not contain a proof or an argument supporting the relation you claim to be valid. Sincerely, A. Einstein. 256. From Chaim Weizmann [London,] W.C. 1, 77 Great Russell Street, 30 June 1922 Highly esteemed Professor, Much to the dismay of all of us I am compelled to impose on you again in the matter of the funds collected by the New Century Club in Boston on the occasion of our joint visit there.[1] As the management of the Club was causing difficulties about the transfer of the collected sums—according to information I received, of the undersigned $20,000, about $4,000 has been deposited up to now—we sug- gested, as you will surely recall, that a special treasurer be appointed for the monies collected in America for the university and library, to whom the sums collected in Boston should be entrusted.[2] Unfortunately, as a result of local squabblings, this proposal did not lead to any result. As all of us right now urgently need whatever funds are available to the library for the purchase of some extraordinarily valuable Judaica libraries, above all the large collection of the deceased Baron Guenzburg in Petersburg, one of the rarest and richest Orientalist libraries existing today, which we can now take over at a bargain price, I would like to make another attempt to make the monies designated specifically to library purposes liquid for these purchases.[3] According to the advice of our just recently returned gentlemen from America, a result might perhaps be achieved if we jointly petitioned the manage- ment of the Boston Club, because they are unable to reach agreement on the busi- ness, to remit the funds directly to a special library account at the local Jewish Colonial Bank to which you and I together should have access. I wrote to this effect