Meteorological observations, 1784


Date: 1784 | Size: 1 volume(s), 1 volume, 33 p.


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.

Background note

David Rittenhouse was an instrument-maker, astronomer, and treasurer of Pennsylvania. Elected to the American Philosophical Society in 1768, he served as its president from 1791 to 1796.

Collection Information

Physical description

1 volume, 33 p.


Presented by Mrs. Henry S. Lowber, 1898; accessioned, 1900.

Early American History Note

This slender volume contains meteorological and some astronomical data taken at Wilmington, Delaware from July 1 to October 14, 1784. In addition to the data, the volume contains marginalia on the weather, his astronomical clock, and his calculations for finishing the Mason-Dixon Line.

Indexing Terms


  • Maps and Surveys
  • Meteorological Data
  • Meteorological records.
  • Scientific Data


  • Astronomy -- Observations.
  • Longitude.
  • Meteorology -- Observations.
  • Pennsylvania History
  • Surveying and Maps