GENTLEMEN; Your semi-weekly of the 1st instant contains a letter of the Hon. Daniel Webster, to certain citizens of Newburyport, in which he has been pleased to refer to me, and particularly to a passage in the letter which I addressed to a portion of my constituents, on the 3d of May last, [the preceding Letter.] His reference to me is of so extraordinary a character, both as to manner and matter, that I wish to reply. To prevent all chance of mistake, I quote the following passages:-- “But, at the same time, nothing is more false than that such jury trial is demanded in cases of this kind by the constitution, either in its letter or in its spirit. The constitution declares that in all criminal prosecutions there shall be a trial by jury. The claiming of a fugitive slave is not a criminal prosecution. “The constitution also declares that in suits at common law the trial by jury shall be preserved; the reclaiming of a fugitive slave is not a suit at the common law; and there is no other clause or sentence in the constitution having the least bearing on the subject. “I have seen a publication by Mr. Horace Mann, a member of Congress from Massachusetts, in which I find this sentence. Speaking of the bill before the Senate, he says: ‘This bill derides the trial by jury secured by the constitution. A man may not lose his horse without a right to this trial, but he may lose his freedom. Mr. Webster speaks for the south and for slavery, not for the north and for freedom, when he abandons this right.’ This personal vituperation does not annoy me, but I lament to see a public man of Massachusetts so crude and confused in his legal apprehensions, and so little acquainted with the constitution of his country, as these opinions evince Mr. Mann to be. His citation of a supposed case, as in point, if it have any analogy to the matter, would prove that, if Mr. Mann’s horse stray into his neighbor’s field, _he cannot lead him back without a previous trial by jury to ascertain the right_. Truly, if what Mr. Mann says of the provisions of the constitution in this publication be a test of his accuracy in the understanding of that instrument, he would do well not to seek to protect his peculiar notions under its sanction, but to appeal at once, as others do, to that higher authority which sits enthroned above the constitution and above the law.”