LETTER FROM BARON VON HUMBOLDT, ON THE DEATH OF VON BUCH.

The following letter from the venerable and illustrious Von Humboldt, announcing in the most feeling manner the death of his friend and scientific associate Leopold Von Buch, will be read with interest by those acquainted with the writings of the great Naturalist.

The letter is addressed to Sir Roderick Murchison.--

"Berlin, March 4th, 1853.--That I should be destined--I, an old man of eighty-three--to announce to you the saddest news that I could have to convey!

Leopold De Buch was taken from us this morning by typhoid fever,--so violent in its attack that two days only of danger warned us.

He was at my house so lately as the 26th [ult.] despite the snow and the distance between us,--talking geology with the most lively interest.

That evening he went into society; and on Sunday and Monday, the 27th and 28th, he complained of a feverish attack, which he believed to be caused by a large chilblain swelling, from which he had suffered for years.

The inflammation required the application of leeches,--but the pain and fever increased.

He was speechless for thirty-eight hours .. He died surrounded by his friends, most of whom knew nothing of his danger till Wednesday evening, the 2d of March.

He and I were united by a friendship of sixty-three years, a friendship which never knew interruption.

I found him in 1791 in Werner's house in Freiburg, when I entered the School of Mines.

We were together in Italy, in Switzerland, in France,--four months in Saltzburg. M. de Buch was not only one of the great illustrations of his age, he was a man of noble soul.

His mind left a track of light wherever it passed.

Always in contact with nature herself--he could boast of having extended the limits of geological science.

I grieve for him profoundly,--without him I feel desolate.

I consulted him as a master; and his affection (like that of Gay Lusac and that of Arago, who were also his friends) sustained me in my labors.

He was four years my junior,--and nothing forewarned me of this misfortune.

It is not at the distance of a few hours only from such a loss, that I can say more respecting it.

Pity me,--and accept the homage of my profound respect and affectionate devotion.

Al. Humboldt.