Benjamin Franklin Papers

Printed in The Pennsylvania Gazette, January 19, 1730/1.

Godfrey’s Almanacks for the Year 1731. Done on a large Sheet of Demi Paper, after the London manner. Containing the Eclipses, Lunations, Judgment of the Weather, the Time of the Sun’s Rising and Setting, Moon’s Rising and Setting, Seven Stars Rising, Southing and Setting, Time of High-water, Fairs, Courts, and Observable Days. With several other Things useful and curious. Printed and sold at the New-Printing-Office near the Market.

N.B. The 3 Mathematical Questions proposed in Leeds’s Almanack,5 were solv’d and answer’d by Godfrey, in less than half an Hour after he saw them, as the Printer hereof can testify; the Solutions and Answers were sent by the Post to the Author of the Questions, together with 3 other Questions for him to Answer; but there being a Pretence that the first Copy of those Questions came not to Hand; and a Second having been sent above 6 Weeks since, concerning which nothing can yet be heard; it is thought proper to publish the said Questions, that there may be no Room for further Excuse. Note, A Copy of the aforesaid Solutions is in the Hands of the Printer.

Question I. Suppose 2 Ships being in the same Latitude, distant from each other 100 Leagues, sail directly North 500 Leagues, (20 in a Degree) and then are 70 Leagues a-part: What are the Latitudes?

Quest. II. Suppose 2 Roads of = Breadth to cross each other at Right-angles in the Centre of a given circular Piece of Ground, and take up the half or third Part of that circular Piece of Ground: What is the Proportion of the Breadth of the Roads to the Diameter of the Circle?

Quest. III. Suppose a Ship in North Latitude, sailing between the North and East,

 makes her Distance 50 Minutes more than her Diff. Latitude. 40 Departure. 30 Diff. Longitude.

What is the Course, Distance, and both Latitudes?

[Note numbering follows the Franklin Papers source.]

4Thomas Godfrey (1704–1749), glazier, self-taught mathematician, inventor of the quadrant called Hadley’s, an original member of the Junto. printed his almanacs for 1730–32, Bradford those for 1733–36. That advertised here was titled The Pennsylvania Almanack for the Year of Christian Account 1731. The Godfreys’ house and ’s shop were in the same building, and boarded with them before his marriage. Of Godfrey wrote in his autobiography that “he knew little out of his way, and was not a pleasing Companion, as like most Great Mathematicians I have met with, he expected unusual Precision in every thing said, or was forever denying or distinguishing upon Trifles, to the Disturbance of all Conversation.” DAB.

5The questions “proposed to the Sons of Art,” to be answered by June 1, 1731, were:

“I. There is a Wall containing 18225 cubical Feet. The Height is five times the Breadth, and the Length eight times the Height. I demand the Breadth of the Wall?

“II. Suppose a Ship sails between the S. and W. till the Sum of the Difference of Latitude and Departure be 7, and her Distance 5. I demand the Difference of Latitude and Departure severally?

“III. Suppose the Area of an equilateral Triangle to be 600. The Sides are required?” The American Almanack For the Year of Christian Account 1731 (Phila., 1730).