32
which is the length of a day hour under Capricorn; but, to find the length of theſe hours at all times of the year by night and day, by the Planisphere, do thus: ſuppoſe, for Example, on the first of August, at 10 hours, 12 minutes in the forenoon; I wish to know the exact time of day, according to the Jews?—Take the Semi-diurnal Arc, by Problem 8, which is 7 hours, 37 minutes, multiply this by 60, and divide the product, 457 minutes by 6, and the quotient is 76m1⁄6, for the length of a Jewiſh hour that day; then rectify the Planisphere to the hour and minute given, 10 hours, 12 minutes, A. M. and ſteady it there; then bring the director to the time of Sun-riſing before found, 23 minutes paſt 4, and carry it warily over 76 minutes, or 1 hour, 16 minutes, and it will then lay over 21 minutes before 6, and call this the first Jewiſh hour; then move it on 1 hour, 16 minutes more, to 5 minutes before 7, and call it the ſecond hour; then to 11 minutes after 8, and it ends the 3d hour; then proceed to 27 minutes paſt 9, for the 4th hour; ſo now, as the director lays, you will plainly ſee there is not another whole hour, before you come to our 12 minutes past 10; ſo count the odd minutes, till the director comes in a ſtraight line with the 1ſt of Auguſt, the hour and minute given, and the Sun's place, and you find 45 minutes towards the 5th Jewiſh hour, with 31 minutes to come to finiſh that hour: by this rule, you will come at the true Chronological time moſtly made uſe of in the Scriptures, and may reduce it, by this laſt Problem, to our time of the day; ſo we find, at the Crucifixion of our Saviour, there was darkneſs
