# NavList:

## A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding

**Re: Contents of Maskelyne's Tables Requisite**

**From:**Bruce Stark

**Date:**2003 Jun 7, 10:01 EDT

Ken, George, & others, Two post I sent yesterday giving the contents of the Requisite Tables apparently didn't go through. I'll try again. Forgot to say in the first post that this is from the Third, 1802 edition. Bruce Ken, I hope we'll be hearing more from you about the surveyors. Maskelyne's trig-log tables are to five decimals, except for sines, which he gives to six places for working Dunthorne's method. Correction tables are to seconds of arc. Here are the tables as listed in the "Contents." Table I. The Refractions of the Heavenly Bodies in Altitude. Table II. Depression or Dip of the Horizon of the Sea. Table III. The Sun's Parallax in Altitude. Table IV. Augmentation of the Moon's Semidiameter. Table V. Dip of the Sea at different Distances from the Observer. (these first five tables on page 1) Table VI. For reducing the Sun's Declination, as given in the Nautical Almanac for Noon at Greenwich, to any other Time under that Meridian; or to Noon under any other Meridian. P. 2-6 Table VII. The Right Ascensions and Declinations of the principal Fixed Stars of the First and Second Magnitudes, adapted to the Beginning of the Year 1796, with their annual Variations. P. 7 Table VIII. For reducing the Apparent Altitude of the Moon to the true. P. 8-17. Table IX. Logarithms for readily computing the true Distance of the Moon from the Sun or a Fixed Star. P. 18-31 Table X. Numbers to be subtracted from the Logarithms in Table IX, when the Moon's Distance from the Sun is observed. P. 33. Table XI. Numbers to be subtracted from the Logarithms in Table IX, when the Moon's Distance from a Star is observed. P. 33. Table XII. The Moon's Parallax in Altitude. P 33. Table XIII. For computing the Effect of Parallax on the Moon's Distance from the Sun or a Star, by Mr. Lyon's Method. P. 34-37. Table XV. Proportional Logarithms. P. 39-55. Table XVI. For computing the Latitude of a Ship at Sea, having the Latitude by Account, Two observed Altitude of the Sun, the Time elapsed between the Observations measured by a common Watch, and the Sun's Declination. P. 57-80. Table XVII. Natural Sines to every Degree and Minute of the Quadrant P. 81-90. Table XVIII. The Logarithms of Number from One to Ten Thousand P. 91-106. Table XIX. Logarithmic Sines, Tangents, and Secants P. 107-152. Table XX. For reducing the Time of the Moon's Passage over the Meridian of Greenwich to the Time of its Passage over any other Meridian P. 153. Table XXI. For reducing the Moon's Declination, as given in the Nautical Almanac for Noon and Midnight at Greenwich, to any other Time under that Meridian; or to Noon or Midnight under any other Meridian P. 154-157. Table XXII. For reducing the Sun's Right Ascension in Time, as given in the Nautical Almanac for Noon at Greenwich, to any other Time under that Meridian; or to Noon under any other Meridian P. 158-160. Table XXIII. For correcting the Latitude computed from the Latitude by Account, Two observed Altitudes of the Sun, and the interval of Time between them P. 161-162. Table XXIV. For correcting the Latitude computed from Two Altitudes of the Sun, &c. P. 163. Table XXV. For correcting the Latitude computed from Two Altitudes of the Sun, &c. P. 164. Table XXVI. For correcting the Apparent Distance of the Moon from a Fixed Star P. 165. Table XXVII. For correcting the Apparent Distance of the Moon from the Sun P. 166. Table XXVIII. For correcting the Apparent Distance of the Moon from the Sun or a Fixed Star P. 167. Table XXIX. The Latitudes and Longitudes of Places, with the Time of High Water at the Full and Change of the Moon, at those place where it is known P. 16-193 [166-193]. Table XXX. The Latitudes and Longitudes of remarkable Places on the Sea Coast of England and Inland P. 195-206. That's the end of the tables. At that point page numbering starts over and runs to 57 more pages: General introduction, explanation of tables, and thirteen "Problems." I'll give you these later. That's enough typing for now. I doubt Robertson's book was much used outside the classroom. Have you seen it? Clearly put together to exercise the minds of students. Not a practical manual. Moore is more likely the one your surveyors used. It incorporates most of Maskelyne and also has the traverse tables, etc. needed for regular navigation. Unlike Robertson, it's small and handy. Do you have any of the surveyors' lunar distance data? Bruce