Tracts, physical and mathematical : containing, an explication of several important points in physical astronomy; and a new method for ascertaining the sun's distance from the earth, by the theory of gravity
A mid-eighteenth-century Scottish mathematical treatise by Matthew Stewart, published in London in 1761 by several booksellers, aimed at astronomers and mathematicians studying physical astronomy and gravitation. Its folding plates are dense geometric constructions of circles, tangents, arcs and ruled lines, lettered with reference letters and figure numbers, offering a designer structured diagrammatic linework and precise compass-and-ruler layouts.
