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. 1901 Excerpt: ...daily, and, at all other times, at rates varying between these two amounts. To secure an invariable unit of time, mean solar time is used, measured in terms of the mean solar day, which is equal in length to the average of all the apparent solar days of the year. Mean solar time is supposed to be regulated by the ...
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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. 1901 Excerpt: ...daily, and, at all other times, at rates varying between these two amounts. To secure an invariable unit of time, mean solar time is used, measured in terms of the mean solar day, which is equal in length to the average of all the apparent solar days of the year. Mean solar time is supposed to be regulated by the movements of a fictitious sun, moving in the equinoctial or celestial equator, at a rate which is the average or mean rate of movement of the true sun in the ecliptic. If tlie imaginary or mean sun and the true sun are supposed to start from the same circle of declination, and return to the same circle at the end of the year, in the interval they are sometimes on the same circle of declination, but generally on different circles, the mean sun being sometimes ahead of the true sun and sometimes behind it. The equation of time is the difference between time measured by the mean sun and time measured by the real sun. This equation of time for every day is always to be found in the Nautical Almanac on pages I and II of each month. To illustrate, by a figure, the meanings of sidereal time, apparent solar time, mean solar time, and the equation of time. Let NWSE represent the horizon; P the pole; WRE the celestial equator or equinoctial; A the first 1f point of Aries; and ABQ the by the angle HP A, or by its measuring arc PA. Apparent solar time is the angle PPB, or its measuring arc RT. Mean solar time is RPm, or the arc Rm. The equation of time is mPT, or arc mT. Thus we may define time by angles measured from the celestial meridian westward. Sidereal time is the angle at the pole of the equi Let B represent the place of the true sun on the ecliptic, and m the place of the mean sun on the equinoctial. Draw circles of declination, PBT and Pm. ecliptic. ...
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Add this copy of Elementary Treatise on Navigation and Nautical to cart. $47.00, good condition, Sold by Shoemaker Booksellers rated 5.0 out of 5 stars, ships from Gettysburg, PA, UNITED STATES, published by American Book Company.
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Very Good- No Dust Jacket. 12mo-over 6¾"-7¾" tall. (1901) 173+pp. Original brown cloth covers w/ gilt title on spine. Binding lightly rubbed w/ light fraying to corners and spine ends. Edges of leaves a bit age toned. A strong, sturdy copy.
Add this copy of Elementary Treatise on Navigation and Nautical to cart. $47.29, good condition, Sold by Bonita rated 4.0 out of 5 stars, ships from Newport Coast, CA, UNITED STATES, published 2010 by Nabu Press.
Add this copy of Elementary Treatise on Navigation and Nautical to cart. $59.79, good condition, Sold by Bonita rated 4.0 out of 5 stars, ships from Newport Coast, CA, UNITED STATES, published 2016 by Palala Press.
