Page:Mathematical collections and translations, in two tomes - Salusbury (1661).djvu/302

 us see whether by withdrawing it 20. minutes onely, it will rise to the height of 32. semidiameters: See the short and true operation. Multiply the sine of the angle BDC, by the sine of the

chord BD, and divide the product, the five last figures being cut off by the sine of the Parallax, and the quotient will be 28. semidiameters, and an half, so that though you make a correction of 4 gr. 22 min. 30 sec. taken from 4 gr. 42 min. 30 sec. it shall not elevate the star to the altitude of 32. semidiameters, which correction for Simplicius his understanding it, is of 262. minutes, and an half.

In the second operation made upon the observations of Hainzelius, and Sculerus, with the Parallax of 0 gr. 8 min. 30 sec. the star is found in the height of 25. semidiameters or thereabouts, as may be seen in the subsequent working.