Buch 
Select mechanical exercises, shewing how to construct different clocks, orreries, and sun-dials, on plain and easy principles : with several miscellaneous articles, and new tables, I. for expeditiously computing the time of any new or full moon within the limits of 6000 years before and after the 18th century II. for graduating and examining the usual lines on the sector, plain scale, and gunter ... : to which is prefixed, a short account of the life of the author / by James Ferguson
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In these Tables I have only num-bered the whole degrees, the inter-mediate lines strewing how manyparts each of them is divided into:as, where there are three such lines,they denote the degree to be dividedinto quarters ; where two, into thirds $and where one, into halves.