Jason J Nassau: A Textbook of Practical Astronomy
There are fourteen chapters, of which the first seven furnish the groundwork of general astronomical facts, co-ordinate systems, time and its conversion, the use of the American Ephemeris, corrections to observations, and the adjustment and use of instruments. The remainder of the book is devoted to methods of determining time, latitude, azimuth, and longitude. Chapters on the astronomical transit and the zenith telescope are included.
A critical reader will find in the introductory material an occasional inconsistency, such as that between Figure i and the text as to dates of perihelion and aphelion, or a place where accuracy has been sacrificed for brevity, as in the statement concerning the distances and nature of nebulae on page 1.
The chapter on instruments is to be especially commended. All the important adjustments are clearly and concisely explained, and methods of using the instruments are described. For each method of determining latitude, time, or azimuth, a schedule of procedure is given. Illustrative examples are numerous, and forms for the recording of observations and for computation are given at the end of the book. Not much excuse is left for slipshod methods of observing, recording, or computing. The chapters on the astronomical transit and the zenith telescope are not long, but treat their subjects with all necessary thoroughness.
Derivations of formulae are not overemphasized, although none is taken for granted except the three fundamental equations of spherical trigonometry. The figures with which the book is illustrated deserve special mention. The most complex of them are remarkably clear as a result of the simple device of heavy-lining the principal parts so that they stand out from the background of reference circles. They form a welcome contrast to the bewildering mazes of intersecting lines to be found in some earlier texts. The relative position of pole and equator in Figure 22 does some violence to perspective, but the meaning of the figure is clear.
JOC/EFR November 2007
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