The art of dialling : performed geometrically ... arthmetically ... instrumentally ... (1700)
Leybourn, William, 1626-1716 · London : T. Braddyll · leaf 146
es on a Vertical or Horizontal Plain 5 in the Latitude 5 1 deg. 3 2 min. Firjl^ Upon your P'lain(or upon a Sheet of Paper )draw a right line A B for the Meridian (or hour-line of 12,) and affigning any point therein (as A) for the Centre of your Dial, through it draw the line C A D at right Angles… … Thirdly , Wish a Needle (or protra&ing Pin) make a . ' Mark
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