. Sun dials and roses of yesterday; garden delights which are here displayed in every truth and are moreover regarded as emblems . the sun isin the beginning, middle, and end of each sign of the in the upright parallel lines at the beginning and middleof each sign make marks for these computed altitudesamong the horizontal parallels of altitude, reckoning themdownward according to the numeral figures set to them atthe right hand answering to the like divisions of the quadrantat the left. And through these marks draw the curve hourlines and set the hours to them, as in the figures
. Sun dials and roses of yesterday; garden delights which are here displayed in every truth and are moreover regarded as emblems . the sun isin the beginning, middle, and end of each sign of the in the upright parallel lines at the beginning and middleof each sign make marks for these computed altitudesamong the horizontal parallels of altitude, reckoning themdownward according to the numeral figures set to them atthe right hand answering to the like divisions of the quadrantat the left. And through these marks draw the curve hourlines and set the hours to them, as in the figures on PlateI, reckoning the forenoon hours downward and the after-noon hours upward. The suns altitude should also becomputed for the half hours. The quarter lines may bedrawn by the eye. Cut off the paper at line AC^ also atline BD^ also cut close to the top and bottom horizontallines. It is then fit to paste on the cylinder. I have given these rules in full not only that anycurious reader may amuse himself by making a shep-herds-dial, but to show the wording of the clearest ofthese old-time mathematical treatises. The drawing. Standard of Dials, with Compass. From Fergusons Lectures. Portable Sun-dials 129 of the lines for a cylinder-dial for the latitude ofLondon were engraved on a sheet of strong paper andsold in large numbers. The story of James Ferguson, the self-taughtastronomer, the author of these rules, and his con-nection with dial-making is interesting. He was athoughtful boy, ever occupied in watching the stars
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectsundial, bookyear1902
