This volume is from the voyage of the China Packet from Philadelphia to Canton, China, and return. The concluding statement reads: "One hundred & thirty days from Maccoa out of which time we had 30 Calm days, the longest passage I Ever had from China. With this Journal I have done and glad Am I."

These logbooks record two voyages (to Corunna, Spain, 1789-1790, and to Oporto, Portugal, 1791, and returns to Philadelphia), with observations of differences in temperature between air and water, especially when passing the Gulf Stream or any land or banks.

Treat sent this volume to Thomas Jefferson in 1809 from "Arkansa in Louisiana," and wrote, "If from their perusal you can derive, either information or amusement, respecting the climate of this part of our country, your acceptance will be highly gratifying."

This journal was kept on a voyage from the Downs to the Capes of Delaware on board the ship Three Sisters, 26 June-20 August, 1803. The volume includes "Observations on the storm glass," made on the same voyage. The storm glass, with an explanation of its use, and the journal of observations are at the American Philosophical Society.

This volume was made at Wilmington, Delaware, for determining the longitude, from 1 July-14 October. It records the position of selected stars and planets. Contains also: Note regarding his astronomical clock, and entries relative to his work in continuing the Mason & Dixon's line.

The first volume contains notes of expenses and of observations while surveying the western boundary of Pennsylvania (1785). Mentions APS under date of Feb. 20, 1784. The second volume contains observations that were continued after Rittenhouse's death to Sept. 30, 1805.

This volume contains medical notes by Wistar, including observations on yellow fever and arguments to prove its foreign origin, facts relative to the progress of the fever in 1797, the infection and death of Colonel Van Emburgh, the infection of the crew of the ship "Deborah" and of the Durham boat (1802), an account of the diseases which afflicted the family of James Hammar in Montgomery County (Pa.), facts relating to the typhus fever of 1812-1813, case histories (1796-1803), temperature chart (1758-1759, 1760), and a thermometrical journal (1760-1765) kept by Charles Norris and copied by Wistar from notes in possession of Joseph Parker Norris.