MINOR PLANETS DISCOVERED BY WATSON— LEUSCHNER. 201 



Classe Pkysicomathematique, Volume XII, No. 11, under the title "Angenaherte Jupitersto- 

 rungen fur die Hecuba-Gruppe." 



A thorough comparison of v. Zeipel's and the author's tables for the group J remains to 

 be undertaken before either are applied to the development of the perturbations of the three 

 planets belonging to the Hecuba type. 



Acknowledgment is due to Prof. Simon Newcomb, chairman of the Watson trustees of 

 the National Academy of Sciences, for his constant efforts in promoting this investigation. 



Acknowledgment is also due to Professor Bohli.n for facilitating the construction of the 

 special tables for the group \ by placing his revised computations for tables of group \ in 

 the author's hands; to Director Campbell, of the Lick Observatory of the University of Cali- 

 fornia, and to Superintendents Asa Walker and W. J. Barnette, of the United States 

 Naval Observatory, for furnishing especially needed observations, and finally to the author's 

 coworkers, particularly to Messrs. Crawford, Ross, and Newkikk, and Misses IIobe and 

 Glancy, for their untiring devotion to the numerical work connected with this undertaking. 



EXPLANATION OF THE TABLES. 

 GENERAL PLAN OF THE TABLES. 



The tables consist of general tables and special tables. The general tables are those tables 

 which are required for all planets in the computation of a geocentric position. The tabular 

 values were computed to one more figure than given in the tables, to insure correctness of the 

 last tabulated figure. Decimals of a degree are used throughout and computations may be 

 readily conducted on the basis of these tables with the aid of Bremiker's five-place logarithmic 

 tables. 



The perturbations, excepting those of (93) Minerva, are developed with the argument 

 dg—i'g'), and a uniform plan is adopted for the special tables of the various planets, except for 

 those, planets for which the development of the perturbations and the construction of tables 

 was originally undertaken elsewhere. In these latter cases the original plan of tabulation has 

 been adhered to to avoid laborious and unnecessary transformations. 



GENERAL TABLES. 



In the general fables are included tables of Jupiter's mean anomaly from 1863, the year of 

 discovery of the first Watson planet, to 1930: Traverse Tables giving the products « sin ^4 and a 

 cos ^4; and a table of Elements. All other general tables necessary for the computation of a 

 geocentric position may be found in Bauschixger's "Tafeln zur Theoretischen Astronomie" 

 and in Tietgex's "Tafel zur Bereclmung der Wahren Anomalie," which may be used in connec- 

 tion with the tables here given. The particular tables to be employed at various stages of the 

 computation of a geocentric position are referred to in the example given on page 215. 



TABLES OF JUPITER'S MEAN ANOMALY, g' (TABLE A). 



The values of g' are tabulated from 1863 to 1930. They are taken from Hill's Tables of 

 Jupiter and Saturn," Tables VIII to XII. The values of g' contained in g—g', Table I of (93) 

 Minerva, however, do not correspond to the values of g' in Table A, since the value of g' used 

 by Eichelberger in building the table g—g' is the undisturbed mean anomaly of Jupiter. 

 It can be obtained by multiplying Arg. I of Hill's Tables for the date +6 d .6 by the mean 

 motion 299".1283756. 



It should also be noted that the dates for which the values of g' and g are given in Tables A 

 and I refer to Berlin mean time, except in case of (93) Minerva, for which Table I refers to 

 Greenwich mean time. 



TRAVERSE TABLES (TABLE B). 



These tallies are to facilitate the formation of the products of the form a sin .4 and a cos A, 

 which occur in the periodic parts of the perturbations, ami are designated, at the foot of "the 



" Astronomical Papers prepared for the use of the American EphenierU and Nautical Almanac. Vol. VII. 



