A Text-book of Field Astronomy for Engineers

Abstract

THIS text-book is designed for the considerable class of technical students who need to make practical applications of the methods of spherical astronomy, but cannot devote to the subject the time necessary for a course such as befits those who wish to study astronomy as a science. Teachers who have to undertake the instruction of such students will study with interest the course which Prof. Comstock has adopted after an experience extending over many years, more especially as no attempt is made to reduce the work to mere rule-of-thumb processes. The introductory chapters include the necessary formulas for the solution of spherical triangles, hints on the orderly arrangement of computations, definitions of coordinates, and a short account of the various corrections to observed data. The methods of observation are classified as rough, approximate and precise according to the degree of accuracy required, and this excellent arrangement not only simplifies the task of the student, but indicates how time may often be saved by avoiding the more refined processes when a comparatively rough result is sufficient for the purpose in view. Some of the processes, described have not usually been introduced into elementary treatises, but all that are given have been found by the author to be well adapted for students. It is not quite clear why the description of instruments is postponed to the part dealing with accurate determinations, seeing that their use is assumed in earlier chapters, but otherwise the sequence is all that can be desired. Some of the “forms” for computation do not seem to be the best that could be devised for beginners, though they are doubtless well adapted to trained workers, and we think they could be made more self-explanatory with advantage to the student. The book deals very completely with the astronomical work involved in surveying, and anyone who masters its contents will obtain a thoroughly sound knowledge of the subject.

A Text-book of Field Astronomy for Engineers.

By G. C. Comstock. Pp. x + 202. (New York: Wiley and Sons; London: Chapman and Hall, Ltd., 1902.) Price 10s. 6d.