763. SO YOU WANT TO BE A SURVEYOR? A fascinating manuscript document, 18pp., 4to., [n.p. c. 1819], a set of detailed notes detailing the rudiments of surveying beginning with basic principles of determining the area of a circle, semicircle, square, etc., as well as the segment of circle and other necessary operations. The notes read in small part: "Surveying is the art of measuring land. The dimensions are usually taken with a chain of 4 Poles in length, which is divided into 100 equal parts called links. But because a chain of this length, is found inconvenient in forests, surveyors mostly measure with a chain of only 2 poles which admeasurement [?] is, however, reduced to four pole chains previous to its insertion in the field book...." The notes contain numerous diagrams and calculations as well as several actual surveys undertaken by the owner once they had mastered the art. An uncommon document. Heavy losses at bottom margin resulting in the loss of some text, a few marginal tears, otherwise good condition. $200-300