ASTRONOMICAL DEPARTMENT. DIAMETER, REVOLUTIONS, &C., OF SUN AND PRINCIPAL PLANETS. 47 1858, Feb. 6. Goldschmidt. Victoria.. 1850, Sept. 13.. Hind. Calypso Euterpe. Vesta Iris 1853, Nov. 8.... Hind. 1807, March 29.. Olbers. 1847, Aug. 13... Hind. 1848, April 25... Graham. 1854, July 22... 1853, April 6.... 1847, July 1... Hind. 1852, Nov. 15... Goldschmidt. 1852, Aug. 22... Hind. 1852, April 17... Luther. 1854, March 1... Marth. 1845, Dec. 8..... Hencke. 1854, Oct. 26.... Goldschmidt. Alexandra Pandora... Mnemosyne Concordia Olympia Chacornac. Danae. De Gasparis. Echo Hencke. Erato Ausonia De Gasparis. Maia Luther. Angelina Maximiliana.. Asia... Leto. 1858, April 4.... 1858, Sept. 10... Goldschmidt. 1858, Sept. 10... Searle. 1859, Sept. 22... Luther. 1860, March 24.. Luther. 1860, Sept. 12... Chacornac. 1860, Sept. 9.... Goldschmidt. 1860, Sept. 14... Ferguson. 1860, Sept. 14... Dr. Forster. 1861, Feb. 11.... De Gasparis. 1861, March 6... Tempel. 1861, March 10.. Tempel. 1861, April 10... Tuttle. 1861, April 18... Pogson. 1861, April 29... Luther. 1861, April 29... Schiaparelli. Goldschmidt. Luther. Feronia 1861, May 29.. Peters. Irene.. 1851, May 19.... Hind. Niobe 1861, Aug. 13. Luther. Thalia 1852, Dec. 15.. Hind. Clytie Eunomia 1851, July 29... Proserpine.. 1853, May 5.. De Gasparis. Luther. Circe 1855, April 6. Chacornac. Juno.. 1804, Sept. 1. Harding. Leda 1856, Jan. 12.. Chacornac. Galatea.. Ceres 1801, Jan. 1..... Piazzi. Eurynome Pallas 1802, March 28.. Olbers. Sappho... 1864, May 2.. Atalanta... 1855, Oct. 5.... Goldschmidt. Terpsichore.. Bellona 1854, March 1... Luther. Alcmena 1864, Nov. 27. Polyhymnia Leucothea Calliope. Payche Themis Euphrosyne. Ariadne. Chacornac. 1854, Oct. 28.... 1855, April 19... Luther. 1852, Nov. 16... Hind. 1852, March 17.. De Gasparis. 1853, April 5.... De Gasparis. 1849, April 12... De Gasparis. 1854, Sept. 1.... Ferguson. 1856, Feb. 8.. Chacornac. 1856, March 31.. Goldschmidt. 1856, May 22.... Goldschmidt. 1856, May 23.. Pogson. 1857, April 16... Pogson. 1857, May 27.... Goldschmidt. 1857, June 28... Goldschmidt. 1857, Aug. 16... Pogson. Beatrix 1863, March 15.. Luther. 1863, Sept. 15... Watson. 1864, Sept. 30... Luther. 1865, April 26... De Gasparis. Pogson. Tempel. Clio... Io. 1865, Aug. 25. Luther. 1865, Sept. 19.. Peters. Semele 1866, Jan. 4... Tietjen. 1866, May 16.. Pogson. Thisbe. (89).. Antiope 1866. Peters. 1866, Aug. 6.. Stephen. 1866, Oct. 1... Luther. (91).. Undina. 1866, Nov. 4.... Stephen. 1867, July 26.... Dr. Peters. 1867, Aug. 24... 1867, Sept. 6. Known to the Ancients. 1781, March 18.. Herschel. 1846, Sept. 23... Le Verrier. Watson. Watson. NEW AND VALUABLE TIDE TABLE FOR ONE HUNDRED AND TEN PLACES. To find the time of high-water at any of the places named in the preceding table, add time indicated in the first column of figures to the time of "Moon's South," or "Moon on Meridian," found in the calendar pages. If the result is more than 12 hours from noon, the time will be the next day in the morning, and if more than 12 hours from midnight, the time will be in ASTRONOMICAL DEPARTMENT. 49 the afternoon of the same day. The tide thus found is the first after the Moon's culmination. The second tide occurs 12 hours and 26 minutes later than the first. The Establishment of the Port," in the above table is the mean interval between the time of the Moon's meridian passage and the time of high-water succeeding that transit. The true interval caries with the Moon's age, being least when the moon culminates about 4h. 30m, and greatest when culminating about 10 o'clock, and at the mean, generally when the moon is two days old. It sometimes happens that the tide comes in several hours later or earlier than the most learned calculation would determine, in consequence of the strength and direction of the wind, which the calculator cannot reckon upon. A TABLE OF SIXTY-ONE BRIGHT STARS. To ascertain when any Star found in the preceding Table will be on the upper meridian, add the numbers opposite in the left-hand column of figures to the time of "Sidereal Noon" found In the calendar pages. For the RISING of a star, subtract the number opposite in the right-hand column of figures from its meridian passage. For the setting of a star, add the same number to its meridian passage. Those marked (....) revolve in a circle of perpetual apparition, and do not rise nor set north of the latitude of New York (40° 42′ 40), for which latitude the semidiurnal arcs are calculated. The civil day begins at midnight, and consequently 24 hours after midnight, or 12 hours from noon, is morning of the succeeding day; and more than 24 hours from noon, is evening of the next day. From 12h. to 24h. from midnight, or from Oh. to 12h. from noon, will be in the afternoon of the same day. This table is arranged in the order of culmination. SURVEYORS AND CIVIL ENGINEERS may obtain the declination of the magnetic needle by observations on the Pole Star when upon the meridian, or when at its greatest elongation cast or west. POLARIS and other stars pass the lower meridian 11h. 58m. after their upper transit. To the time of upper transit of Polaris, add 5h. 54m. and it gives the time of greatest western elongation. If the 5h. 54m. be subtracted from the time of upper transit, it will give the time of greatest eastern elongation. Observations made at the time of greatest elongation are less liable to error than those made at the time of transit. The mean distance of Polaris from the pole this year is 1° 23′ 20. To find its azimuth for any latitude, take from 18.384502 the logarithmic cosine of the latitude, and the remainder is the logarithmic sine of the azimuth. 4 |