SAMUEL MOORE, An Accurate System of Surveying, (Litchfield [CT], 1796), 131 pages of text including 8 pages of tables.

Moore's Surveying is claimed by some to be the first totally American work on the subject. It was written by an American-born author and published in Connecticut. The distinction of being first is also claimed for John Carter's The Young Surveyor's Instructor published in Philadelphia 22 years earlier. Carter's work, however, reportedly lacks a significant content. Most agree, however, that Moore's work is the first substantive American book on surveying.

Samuel Moore was born in Connecticut and practiced surveying for over 30 years before writing this book. He wanted to share his knowledge with others in order to upgrade the level of surveying practice. Most of the problems he addresses involve mathematics rather than field measurement. He was dissatisfied with the common practice of determining area by plotting a survey on paper, dividing the parcel into triangles by connecting various exterior points, and then determining the areas of the triangles by using scaled dimensions. He suggested, for example, that practitioners calculate the area by using a variation of the technique of double meridian distance. Other highlights involve the mathematics of dividing land and surveying parcels of a set area.

Moore expressed no particular concern on the correctness of field measurements. Instruments are not described, nor are instructions given on their use. Occasional references are made to use of the compass and chain, but nothing about the other instruments of the period. From this, one deduces Moore's own surveying practice concentrated upon rural property surveys.

The book contains eight chapters. The first four cover mathematics including decimal fractions, square root, rectangular and oblique trigonometry, and some geometry. Next in order appear four brief trigonometrical tables that Moore presented in a unique fashion. First is an 8 place table of natural sines for every half degree, not including even degrees. The next table is an 8 place table for natural sines for even degrees. Following is a one-page 7 place table for finding the sine of minutes. The 4th and final table is for tangents at one degree intervals. Moore considers these tables adequate for surveying.

A chapter ostensibly on practical surveying follows the function tables. Its subject matter deals with the application of mathematics to surveying. The first example determines area by using a variation of the double meridian distance technique. The chapter also includes a discussion on balancing a survey. The balancing method first totals the columns of eastings and westings, and the northings and southings. The lesser sum between the eastings and westings columns is considered correct, and the individual figures in the column with the higher sum are reduced proportionately so that the sums of the two columns are the same. The northings and southings are similarly made equal, again considering the column with the least sum to be correct. Finally this chapter treats how to lay out a tract of land containing a set acreage.

Chapter VI treats the mathematical division of lands. It begins with how to divide a triangular area and continues to more complicated tracts with additional sides. One example shows how to set off 50 acres of land along an irregular northern boundary. Chapter VII on field surveying continues with the field layout of a tract and its corresponding area. Again the focus is on the mathematical elements. This chapter also discusses how to determine angular values corresponding to linear measure.

The final chapter deals with various useful propositions. It explains how to reduce inclined measure to horizontal, to measure across a river, to solve intersection problems, and to renew lost boundaries. The final chapter also offers some useful comments regarding how to operate the compass instrument. Discussions then follow on how to determine the variation of the magnetic compass needle and how to ascertain local attraction. Determining the true meridian in the field is presented in terms of using the morning and afternoon shadows cast by a vertical staff.

Moore's purpose in writing the book was to help remedy the unsatisfactory methods of property surveying then being conducted. Nothing specific is given on how to measure direction or distance, nor are instruments or tools described. It is expected that readers were already proficient in their use. What stands out about 1790's surveying skills in Connecticut is the deficiency in application of the mathematical sciences. Moore's effort was a small step to correct that shortcoming. Although short-lived and limited to a single edition, it enjoys a distinct status as the first substantive American surveying book. It is a rare treatise and highly sought by serious collectors.

Reprinted from P.O.B., Vol. 23, No. 3, December 1997, by permission of Business News Publishing Company, Troy, MI.