28 



MEMOIRS NATIONAL ACADEMY OF SCIENCES. 



[Vol. xrv. 



tions. This substitution produced an unfavorable distribution of the observed places in the 

 orbit and the resulting least .scjuarcs solution was not satisfactory. 



In the meantime, pending a resumption of the least squares solution on the basis of a more 

 favorable distribution of observed places/ the following conclusions may be drawn regarding 

 the revised and v. Zeipel's original tables: 



1. V. Zeipel's tables have been slightly improved by the correction of some numerical errors. 



2. A moderate further improvement has been accomphshed by an extension of the tables 

 in so far as seemed practicable without a more exhaustive and unwarranted study of the prac- 

 tical convergence of the auxiliary series, by including certain terms of higher order and degree. 



With reference to the correction of the orbit and the representation of observations by a 

 least squares solution, it should be observed that 



(1) A symmetrical distribution of the observed positions in the orbit is essential to coun- 

 teract the effect of neglected perturbations of higher order and degree and of major planets 

 other than Jupiter. For the Hecuba Group, in general, the mean motions of the minor planets 

 may be nearly commensurable with those of Saturn, Mars, or the Earth in the ratios 3/2, 3/1, 

 or 3/5. 



(2) However accurate the initial osculating elements may be, comparatively large residuals 

 may remain on account of neglected perturbations. 



Logaritlimic. 



Table A (XXXV). 

 nSz—[nSz] 



Unit-l" 



■ Since 1913, when the revision of the tables was concluded, Miss Glancv has continued the problem of (10) Ilijgka independently at the Ohser\a- 

 torio Nacional, C6rdoba, with the following highly satisfactory results, which substantiate further the increased accuracy of the revised tables 

 (1) The original osculatin<; elements and the revised tables resulted in a greatly improved representation of the selected observations (is^9-lssi) 

 over the representation ojjtained with the original tables. (2) After the correction of the original osculating elements by least squares solution 

 (a) on the basis of v. Zeipel's tables and residuals, (b) on the basis of the residuals resulting from the revised tables, the representation ol the 

 selected observations was equally satisfactory; but 3 later observations, taken in 1910, 1914, and 1917, are represented tar better by the revised 

 tables and correspondins elements than by the original tables and corresponding elements, (cf. Astronomical Journal, Vol. 32, p. 27, No. 748, 

 January 1919) A. O. Lcuschncr. 



