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This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1825 Excerpt:...--2. 50 1 Mean time at Canton 10. 2.53.35-2 Chronometer showed 7.26.32, which increased by 12b, is 9.19. 26.32 '0 Longitude of Canton by chronometer =7.27. 3-2 True longitude of Canton in time--7.32.56 '0 Error of chronometer, fast on Greenwich mean time 5.528 For further information respecting the transit instrument, see articles 95 to 128. Table XXXI.--For reducing Mean Time to Sidereal Time. (658) The arguments of this Table are hours, minutes and seconds of mean time; and the redaction is expressed in minutes, seconds and hundredth parts, which being collected and tided to the mean time by which it was taken wt, will give the sidereal time required. This Table is useful in reducing the interval between he observed altitudes of any one or more stars. (659) Example.--Suppose the elapsed time easured by a watch between the altitudes of tie same, or two stars, be lh. 45". 30"; required the interval in sidereal time? 1" in Tab. XXXI. gives 9"86 « 657 J" 0-82 50» 0-08 Elapsed time per watch 1.45.30.00 Interval in sidereal time 1.45.47 "33 (660) In working double altitudes by the Stan to determine the latitude, the elapsed time shown by a chronometer or watch must always bt reduced after the method art. 659; this is the only difference in the computation with that employed in finding the latitude by double altimdes of the sun; and since the change of a "--» declination is nothing in so short an inerval, they are to be preferred to the sun, protiitdthe horizon he well defined. Table XXXII.--For finding the Proportional Part of the Annual Precession of the fixed Start for any Number of Days less than a Tear. (661) The use of this Table being chiefly explained at its head, it is only necessary to give aa example o...