TJ’s most recent letter to Watterston was dated 3 Jan. 1816, not the 10th.

On 15 Dec. 1815 the United States House of Representatives referred a resolution seeking in part “additional compensation to the librarian for services performed since the last session of Congress” to the joint library committee (JHR description begins Journal of the House of Representatives of the United States description ends , 10:62). In their report presented to the Senate on 26 Jan. 1816, the committee determined that the “only evidence of the literary services of the librarian within the knowledge of your committee is, the publication of the catalogue with which we were presented at the beginning of the session; and the merit of this work is altogether due to Mr. Jefferson, and not to the librarian of Congress. Your committee are persuaded that, however ingenious, scientific, philosophical, and useful such a catalogue may be in the possession of a gentleman who (as was the case with the former proprietor of this, now the library of Congress) has classed his books himself, who alone has access to them, and has become, from long habit and experience, as perfectly familiar with every book in his library as a man who has long lived in a city is familiar with every street, square, lane, and alley in it, still this form of catalogue is much less useful in the present state of our library, consisting chiefly of miscellanies not always to be classed correctly under any particular head, than a plain catalogue in the form which had been adopted for the formation of the catalogue of the old library, which probably might not have cost more than $100 (if that much) whilst the catalogue with which we were presented, including three copies of it bound, calf gilt, costs the United States $1,360 50, one-third more than the annual appropriation made heretofore by Congress for the additional increase of the library, and more than one-twentieth of the actual cost of our whole library” (ASP, Miscellaneous, 2:280).