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is easy to unite two branches of instruction, which are so important and so analogous. Artists and mechanicks ought to be able themselves to measure their work, whatever it may be; and to draw plans, to make contracts for work, to calculate the price and quantity of materials necessary for the work; and, in fine, to make all the estimates required by the art they practise.

To enable them to do this, we shall unite the elements of Geometry and Arithmetick, explain the problems and rules of most common occurrence, and add numerical examples to illustrate their application. The master will vary the examples at pleasure.

Inches are divided into tenths, hundredths, thousandths, &c. and calling the inch unity, or a whole, we place a comma at the right hand of it to separate the fractions or parts. For example, to express 8 inches and 6 tenths, we write 8,6; for 9 inches and 72 hundredths, we write 9,72; for 10 inches and 626 thousandths, we write 10,626, and so on. If there be no whole inches, a cipher is put in the place of inches, and the comma as before, thus, 0,382 stands for 382 thousandths of an inch, or as the first column at the right of