"People's Sunday Meeting," Boston Investigator, 18, 45 (March 14, 1849), 3.
People's Sunday Meeting:—Mr. Warren's lecture last Sunday afternoon on Music was well attended, and listened to with much interest. He commenced by going into a long and critical examination of the present system of teaching the art, and after showing the difficulties of acquiring it in consequence of the vague and ambiguous mode in which it is written, he presented his new system of writing music, which he maintained was so simplified and easy to understand as to be reality acquired by the masses. He has paid much attention to the subject, have been in early life a musician in the orchestra of the Federal Street Theatre in this city, and for the last twenty-five years an occasional teacher. His new system is therefore the result of long and careful study, and notwithstanding he might have it patented, and no doubt make not a little money by it, yet with his characteristic liberality he foregoes the advantage of money and fame, and gives his discovery freely to the public. We are not able to criticise his system and show all its merits, but we understood him to say that it bears about the same relation to the present method of writing music, that phonography does to the old system of spelling.
At the conclusion of the lecture, the audience gave him a unanimous vote of thanks.