OF DIALING. 355 



the radius C A, describe the semicircle A E L, and 

 divide it into 12 equal parts (beginning at A) as A r, 

 A s, &c. and from these points of division, draw the 

 hour-lines r, s, f, it, r, E, ic, and x, all parallel to the 

 sis o'clock line _E C. If cadi part nf the semicircle be 

 subdivided into four equal parts, they will give the half- 

 hour lines and quarters, as in fig. 2. Draw the right 

 line A S D o, making the angle SAB equal to the 

 latitude of your place. Upon the center A describe the 

 arch R S T, and set off upon it the arcs .S' R and 5 T 

 each equal to 23i degrees, for the sun's greatest decli- 

 nation ; and divide them into 23 equal parts, as in fig. 2. 

 Through the intersection D of the lines EC D and 

 A D o, draw the right line FD G at right angles to 

 A D o. Lay a ruler to the points A and R, and draw 

 the line A R F through 23^ degrees of south declination 

 in the arc S R ; and then laying the ruler to the points 

 A and T, draw the line A T G through 23i degrees of 

 north declination in the arc S T: so shall the lines 

 A R F and A TG cut the line FD G in the proper 

 length for the scale of months. Upon the center D. 

 with the radius D F, describe the semicircle FoG: 

 and divide it into six equal parts, F m, m n, n o, &c. 

 and from these points of division draw the right lines 

 m h, n i, p k, and q I, each parallel to o D. Then setting 

 one foot of the compasses in the point F, extend the 

 other to A, and describe the arc A z H for the tropic 

 of vf : with the same extent, setting one foot in G, de- 

 scribe the arc AEO for the tropic of s. Next set- 

 ting one foot in the point h, and extending the other to 

 A, describe the arc A C I for the beginnings of the 

 signs zz and f ; and with the same extent, setting one 

 foot in the point /, describe the arc A -V for the begin- 

 nings of the signs n and il. Set one foot in the point 

 i. and having extended the other to A, describe the arc 

 AK for the beginnings of the signs X and nj. ; and with 

 the same extent, set one foot in k, and describe the arc 

 2 A 2 



