OF DIALING. 349 



But because every one who would like to make a 

 dial, may perhaps not be provided with a globe to 

 assist him, and may probably not understand the An 

 method of doing it by logarithmic calculation ; we shall for con- 

 shew how to perform it by the plain dialing lines, or 

 scale of latitudes and hours ; such as those in plate V, or 

 at the top of plate VI, and which may be had on scales 

 commonly sold by mathematical instrument makers. 



This is the easiest of all mechanical methods, and by 

 much the best, when the lines are truly divided : not 

 only the half hours and quarters may be laid down by 

 all of them., but every fifth minute by most, and every 

 single minute by those where the line of hours is a foot 

 in length. 



Having drawn your meridian line a b, c d, (fig. 3.) 

 on the plane intended for a horizontal dial, and crossed 

 it at right angles by the six o'clock line fe (as in 

 fig. 1.) take the latitude of your place with the com- 

 passes, in the scale of latitudes, and set that extent from 

 c to e, and from a toj, on the six o'clock line : then, 

 taking the whole six hours between the points of the 

 compasses in the scale of hours, with that extent set one 

 foot in the point c, and let the other foot fall where it 

 will upon the meridian line c d, as at d. Do the same 

 from y* to b, and draw the right line edandfb, each of 

 which will be equal in length to the whole scale of 

 hours. This done, setting one foot of the compasses in 

 the beginning of the scale at XII, and extending the 

 other to each hour on the scale, lay off those extents 

 from d to e for the afternoon hours, and from b tof for 

 those of the forenoon : this will divide the lines d e and 

 bf in the same manner as the hour-scale is divided, at 

 1, 2, 3, 4, 5 and 6 ; on which the quarters may be also 

 laid down, if required. Then, laying a ruler on the 

 point c, draw the first five hours in the afternoon, from 

 that point, through the dots at the numeral figures 1, 2, 

 3, 4, 5, on the line de; and continue the lines of IV and 



