Alexander von Humboldt addresses the following letter to the Vossische Zeitung of Berlin:--"

Burdened by an every-day growing correspondence, which in the mean amounts to from 1,600 to 2,000 numbers per annum--(letters, books and pamphlets, on subjects completely uninteresting to me; manuscripts about which I am asked to give my advice; projects of emigration and colonisation; specimens of models, of machinery, and of objects of natural history; questions about aerostats; demands for autographs; offers to nurse and to amuse me, &c.)--I try once more, by means of this public notice, to invite persons who really have any regard for me not to occupy themselves so much with my person, on this and on the other side of the Atlantic; and, above all, not to make a post-office of my house.

I feel but too much already the diminution of my mental and physical powers, and a little rest and leisure after my day's work is absolutely necessary to me.

And may this appeal, to which I have been driven by direst necessity, not be unkindly taken.

Alexander von Humboldt.

Berlin, March 15, 1859.