The 18th century was a wealth of knowledge, exploration and rapidly growing technology and expanding record-keeping made possible by advances in the printing press. In its determination to preserve the century of revolution, Gale initiated a revolution of its own: digitization of epic proportions to preserve these invaluable works in the largest archive of its kind. Now for the first time these high-quality digital copies of original 18th century manuscripts are available in print, making them highly accessible to libraries, undergraduate students, and independent scholars. Medical theory and practice of the 1700s developed rapidly, as is evidenced by the extensive collection, which includes descriptions of diseases, their conditions, and treatments. Books on science and technology, agriculture, military technology, natural philosophy, even cookbooks, are all contained here.++++The below data was compiled from various identification fields in the bibliographic record of this title. This data is provided as an additional tool in helping to insure edition identification: ++++Harvard University Houghton LibraryN011698Frontispiece signed: John Gilbert. Mathematical Instrument-Maker, on Tower-Hill, London. John Gilbert active between 1767 and 1794; another, dated, edition, apparently from the same press, was published in 1790. In this undated edition, there is no comma after preface and the word 'theory' is set in large capital letters. London, 1790?]. viii, 24p., plate; 8 | The Nature And Use Of Hadley's Quadrant With A Preface Containing The Theory On Which That Noble And Useful Instrument Is Founded. And A