P.S. I rec^d this morning since the above was written a letter from Carl Vogt, expressing his readiness to translate my book at the request of the publisher Monsieur Ricker.² I shall write to him tomorrow to say that you have undertaken the work, & I mention the circumstance because if you sh^d unfortunately for me find yourself, now that you know the size of my book, too much overwhelmed with your own work to complete the translation within any reasonable time, I should not be quite thrown over, as Schweizerbart³ could perhaps arrange with Prof. Vogt. But I trust there may be no need for any change—