478 Scientific Intelligence. 



play an important part are discussed, with special reference to 

 those found in the literature of Germany. The work is of liter- 

 ary rather than of scientific interest. a. w. e. 



III. Miscellaneous Scientific Intelligence. 



1. Die Bahnbestimmung der Hhnmelskorper y von Julius 

 Bauschinger. Pp. 653, with 84 figures. Leipzig, 1906 (Wil- 

 helm Engelmann). — The present volume is of particular interest 

 since, coming from the hands of the able director of the Berlin 

 Jahrbuch and Computation-bureau, the opportunities for practi- 

 cal testing of the methods have been unsurpassed. Also since 

 the date of Watson's treatise of some 40 years and that of Oppol- 

 zer of some 20 years ago, which may be said to have covered the 

 field of comet and asteroid orbit-computation at their epoch, and 

 that of the less comprehensive but valuable works of Klinkerfues, 

 Frischauf,* Moulton and others, a number of important contribu- 

 tions to this branch have been made. An especially interesting 

 feature of Dr. Bauschinger's work are the historical sketches of 

 the various phases of the problem. 



The treatise is divided into seven parts, the first three of which 

 treat of the coordinates, the heliocentrics and the geocentric 

 motion of a body moving about the sun according to Kepler's 

 laws. 



Part four gives the solution of the problem of a first orbit and 

 it is noteworthy to find that both for an ellipse from three ob- 

 served positions and a parabola the methods presented in detail 

 are substantially the Gauss-Encke and Gauss-Hansen for the 

 former and the Lambert-Olbers-Gauss for the latter. The remark- 

 able formulae of Gibbs, which are probably the most striking 

 contribution of late years to the domain of orbit-computation, are 

 briefly considered with modifications of Gibbs' original some- 

 what involved method ; and reference is made to the ingenious 

 methods of Weiss, Fabritius and others. For the exceptional 

 case where four observations are requisite an expeditious method 

 of the author is presented. The so-called direct methods, where 

 three or any number of observations may be used, are briefly 

 treated ; the Laplace-Bruns method alone is given in full and 

 reference only made to the work of Harzer, Leuschner and others. 

 • Part five comprises the determination of a definitive orbit from 

 all available observations by the method of least squares, and part 

 six the theory of special perturbations, examples being given for 

 the variation of constants and the perturbations in rectangular 

 coordinates. 



In part seven are found methods for orbits of meteors, satellites 

 and binary stars. 



Dr. Bauschinger has already published a collection of numerical 

 tables for use in theoretical astronomy and the two works 



* To which, an appendix with an application of Gibbs' principle has lately 

 been issned by the same publishers. 



