Printed in John Gordon’s Mathematical Traverse Table, &c. Printed in the Year 1758, and Sold by Mr. W. Dunlap, in Philadelphia, Mr. G. Noel, in New-York, Mr. B. Mecom, in Boston, and by the Author. (Yale University Library)6
John Gordon (1700–1778), a former Philadelphian now living near Princeton, N.J., managed to combine the trade of a bricklayer with the teaching of surveying and other mathematical arts.7 In the spring of 1757 he announced his intention of publishing by subscription a set of tables to assist “Mariners, Merchants, and Surveyors” in their calculations. As a matter of timely importance he added that his work would also “be of great use to all Military Gentlemen in any Part of the World, in forming their Marches, or other important Schemes or Designs of an Army.” To this announcement in the newspapers and to the prefatory statement in the book itself, when it appeared the next year, he appended a series of testimonials as to the utility of his tables.8 The first three of these endorsements are printed here, comprising the comments of two New Jersey surveyors and of one from Pennsylvania, and, perhaps inevitably, one by Franklin. It will be noticed, however, that the last of these wisely offered no personal judgment on the value of Gordon’s tables—a matter probably beyond Franklin’s mathematical competence—but merely endorsed the endorser just before him.
New-Jersey, March 8th, 1757.
We are of Opinion that if the above Tables were printed and published, they would be of great Use to the Public, in Measuring of Land and other Branches of the Mathematicks.
I am of the above Opinion.
Nicholas Scull, Surveyor Gen. of Pennsylvania.
Philadelphia, March 11, 1757.
The above written Mr. Scull is well known to be one of the best Judges of these Matters in this Province, and therefore any Opinion of mine, or Certificate, is unnecessary after his.
Benjamin Franklin, Post Master General.
6. Evans 8140.
7. Gordon gives a brief sketch of his career on the second page of the tables. An abstract of his will appears in I N.J. Arch., XXXIV, 207.
8. The advertisement first appeared in Pa. Jour., April 14, 1757; it was reprinted in several succeeding issues and also appeared in N.Y. Mercury as late as May 20. The names and number of endorsers varied in the different advertisements; in the book itself there are nine testimonials, altogether bearing the names of fourteen individuals from Pennsylvania, New Jersey, and New York.