## Lunar and horary tables, for new and concise methods of performing the calculations necessary for ascertaining the longitude by lunar observations, or chronometers: with an appendix, containing directions for acquiring a knowledge of the principal fixed stars |

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### Common terms and phrases

0F THE SUN 0R STAR 58 Logarithms 8e taken Add for Seconds alti APPARENT ALTtTUDE 0F Apparent Distance arch Argo Navis astronomical Centaurus Chronometer Constellation Corr deduced degrees Deneb Diff Dist fast for mean find the error fixed Star Greenwich Half Sum horary angle Latitude Latitude and Polar Logarithms of Numbers lower limb Lunar Distances method minutes Moon's Apparent Altitude Moon's hor moon's horizontal parallax natural number Natural Versed Sines Nautical Almanac nearly object observed altitude observed distance ooooo opposite past the Meridian place of observation PoIe Polar Distance Pole Star Port Louis prime vertical refraction required the true right ascension SEC0ND DtFFERENCE Second Corrections Seconds of Parallax semid Sextant Ship slow for mean subtracted SUM 0R DtFFERENCE Sum and Difference Sun and Moon Sun's right ascension telescope Third Correction true altitude true distance tude Ursa Major

### Popular passages

Page 44 - C, as seen above, are constants, depending upon the latitude of the place of observation and the declination of the star. Tables for these quantities will be found in an appendix to Annual Report US Coast and Geodetic Survey for 1874.

Page iii - Eaft and the other to the Weft of the Meridian, the Time will be determined with rather more certainty. The Manner of computing the apparent Time from the Altitude of the Sun or a Star is fl1ewn by Problems VIII.

Page 226 - Subtract the true altitude of the sun's centre from 90°, and the remainder will be the sun's true meridian zenith distance, which is to be called north or south according as the observer is north or south of the sun at the time of observation.

Page 5 - ... will be the right ascension of the meridian. From the right ascension of the meridian (increased by 24 hours if necessary) subtract the sun's right ascension...

Page 18 - Rule. — Find the latitudes of both places; if both be north, or both south, their difference will be the answer; but if one be north and the other south, their sum will be the answer. Exercise.— What is the difference of lat. between Philadelphia and Petersburg? Ans., 20 degrees. Between Madras and Waterford? Am., 39° 13'.

Page 227 - Then, if the zenith distance and declination be both north or both south, add them together; but if one be north and the other south...

Page 228 - For ßnding the Latitude by an Altitude of the Polar Star. This table is to be entered with the right ascension of the meridian at the time of observation ; the correction corresponding to which being added to, or subtracted from, the true altitude of the Polar Star, as denoted by the sign + or —, the sum or remainder will give the latitude of the place of observation, which is always North. The table is calculated particularly for the years...

Page 11 - If the sun or star be at a proper distance from the meridian, the time may be inferred from its altitude...

Page 6 - Let the apparent distance between the Moon and a Fixed Star be 72° 0

Page 219 - Stars as follows 1 the first letter of the Greek alphabet being attached to the name of any Constellation points out the brightest Star in that Constellation; the second letter the next in brightness, and so on. When the number of Stars in a Constellation exceeds the number of letters in the Greek alphabet, the letters of the 1talic alphabet are next used, then those of the Roman alphabet, if required 1 and when the number of the remaining Stars are distinguished by means of the common numericals.