. Encyclopaedia; or, A dictionary of arts, sciences, and miscellaneous literature; constructed on a plan, by which the different sciences and arts are digested into the form of distinct treatises of . V r . . /I/.J *y I Plate Ilraclcara SfJ/ D I A I N G. adjufled (late: to perform which, 3ou try t]ie levels of to the right and left, till the latitude arch C fills the horizontal pkites yj a, by iirft turning the fcrewsBBBB till the bubbles ot air on the glafs tubes of thefpirit-levels (levels are at right angles to each other)which are central or in the middle, an
. Encyclopaedia; or, A dictionary of arts, sciences, and miscellaneous literature; constructed on a plan, by which the different sciences and arts are digested into the form of distinct treatises of . V r . . /I/.J *y I Plate Ilraclcara SfJ/ D I A I N G. adjufled (late: to perform which, 3ou try t]ie levels of to the right and left, till the latitude arch C fills the horizontal pkites yj a, by iirft turning the fcrewsBBBB till the bubbles ot air on the glafs tubes of thefpirit-levels (levels are at right angles to each other)which are central or in the middle, and remain fowhen you turn the upper plate A half round it?centre ; but if they Ihould not keep fo, there are fmallfcrews at the end of each level, which admit of beingturned one way or the other as may be requifue tillthey are fo. The plates An being llius made horizon-tal, fetthe latitude arcli or meridian C Iteadily betweendie two-grooved fides that hold it (one of whiclj is feenat D), by the fcrew behind. On this fide D is dividedthe nonius or vernier, correfponding with the divifionson the latitude arch C, and which may be fubdividedinto 5 minutes of a degree, and even Icfs if latitude arch C is to be fo placed in D, that
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Keywords: ., bookcentury1700, bookdecade1790, booksubjectencyclo, bookyear1798
