Letter from William Croswell to Thaddeus Harris, 1820 May 22

Handwritten copy of a one-page letter requesting advice about the Harvard Library Catalogue.

Letter from William Croswell to Thaddeus Harris, 1821 May 16

Draft of a letter regarding the Harvard Library Catalogue.

[Admittatur of Thaddeus W. Harris], 1811 September 24

Published copy of the 1814 College Laws with the admittatur of undergraduate Thaddeus W. Harris signed by President John Kirkland on September 24, 1811.

An oration, Thaddeus M Harris A.M. now minister of Dorchester, 1790

This small paper notebook contains a twenty-one-page handwritten oration on learned societies delivered by Phi Beta Kappa member Thaddeus Mason Harris on September 1, 1790. The oration is followed by five pages of "notes and illustrations" on the text. Title transcribed from title page. Item bound in blue-and-white floral wallpaper covers.

Letter from William Harris to Samuel Shapleigh, 3 January 1791

Includes response and receipt for payment of £10 from butler Samuel Shapleigh.

Mathematical notebook attributed to Thaddeus Mason Harris, ca. 1787

Hardcover notebook containing handwritten transcriptions of rules, cases, and examples from 18th century mathematical texts. The author and purpose of the volume is unclear, though it has been connected with Thaddeus Mason Harris (Harvard AB 1787). Most of the entries include questions and related answers, suggesting the notebook was used as a manuscript textbook and workbook. The extracts appear to be copied from John Dean's " Practical arithmetic" (published in 1756 and 1761), Daniel Fenning's "The young algebraist's companion" (published in multiple editions beginning in 1750), and Martin Clare's "Youth's introduction to trade and business" (extracts first included in 1748 edition).