☞ 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 6imits of 6000 years before and after the 18th century : II. for graduating and examining the usual lines on the sector, plain scale, and gunter : illustrated with copper-plates : to which is prefixed, a short account of the life of the author.