### Popular passages

Page 3 - The circumference of every circle is supposed to be divided into 360 equal parts, called degrees; and each degree into 60 minutes, each minute into 60 seconds, and so on.
Page 30 - U to their difference, fo is the tangent of half the fum of thofe arches, to the tangent of half their difference; and, As the fum of the...
Page 4 - The fine, or right-fine, of an arch, is a right line drawn from one extremity of the arch, perpendicular to the diameter paffing through the other extremity. Thus BF is the fine of the arch AB or DB.
Page 33 - ... fo is the tangent of half the vertical angle, to the tangent of the angle which the perpendicular CD makes with the line CF, bifcding the vertical The Solution of the Cafes of righl-angled fpfierical Triangles, (Fig.
Page 33 - ABC, it will be, as the co -tangent of half the fum of the angles at the bafe, is to the tangent of half their difference, fo is the tangent of half the...
Page 43 - JJ/xJV; hence, The sum of the logarithms of any two numbers is equal to the logarithm of their product. Therefore, the addition of logarithms corresponds to the multiplication of their numbers.
Page 5 - BI, the sine of its complement HB. The tangent of an arc, is a right line touching the circle in one extremity of that arc, continued from thence to meet a line drawn from the centre through the other extremity ; which line is called the secant of the same arc : thus AG is the Ungent, and CG the secant of the arc AB.
Page 4 - A chord, or fubtenfe, is a right line drawn from one extremity of an arch to the other ; thus B � is the chord or fubterife of the arch BAE, orBDE.
Page 13 - The straight line BE between the centre and the extremity of the tangent AE, is called the Secant of the arch AC, or of the angle ABC. COR. to def.