First, as regards what may be termed professional bibliography. One of the earliest workers in the new spirit was a Dresden jurist, Hermann E. Ludewig, who came to the United States in 1844, and prepared an account of the _Literature of American local history_, which was published in 1846. This was followed by a supplement, pertaining wholly to New York State, which appeared in _The Literary World_, February 19, 1848. He had previously published in the _Serapeum_ at Leipsic (1845, pp. 209) accounts of American libraries and bibliography, which were the first contributions to this subject.[32] Some years later, in 1858, there was published in London a monograph on _The Literature of the American Aboriginal Linguistics_,[33] which had been undertaken by Mr. Ludewig but had not been carried through the press, when he died, Dec. 12, 1856.[34] We owe to a Franco-American citizen the most important bibliography which we have respecting the first half century of American history; for the _Bibliotheca Americana Vetustissima_ only comes down to 1551 in its chronological arrangement. Mr. Brevoort[35] very properly characterizes it as “a work which lightens the labors of such as have to investigate early American history.”[36] It was under the hospitable roof of Mr. Barlow’s library in New York that, “having gloated for years over second-hand compilations,” Harrisse says that he found himself “for the first time within reach of the fountain-heads of history.” Here he gathered the materials for his _Notes on Columbus_, which were, as he says, like “pencil marks varnished over.” These first appeared less perfectly than later, in the _New York Commercial Advertiser_, under the title of “Columbus in a Nut-shell.” Mr. Harrisse had also prepared (four copies only printed) for Mr. Barlow in 1864 the _Bibliotheca Barlowiana_, which is a descriptive catalogue of the rarest books in the Barlow-Aspinwall Collection, touching especially the books on Virginian and New England history between 1602 and 1680.