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THE ROYAL SOCIETY OF CANADA 



A summary of the previous work on the orbit which has consider- 

 able bearing on this later determination will now be given. It was 

 found necessary to carry through three least squares solutions of the 

 orbit. In the first ont; of these a correction for the period was introduced ; 

 but when this correction was carried forward to the Lick and Yerkes 

 observations it was found to be quite inapplicable and consequently 

 the period was determined as closely as possible from a comparison 

 of the early with the Ottawa values and the coefficient for this cor- 

 rection omitted from the later solutions. 



The second solution resulted in such a large increase of K and 

 consequent rise of the positive maximum velocity above any observed 

 values as again to be inadmissible. This was undoubtedly due to 

 the absence of any Ottawa observations near the peak of the curve 

 which of course was very sharp with the high eccentricity of about 0-7. 

 For the third solution therefore one Lick observation of + 80 km and 

 one Yerkes of + 88 km, taken on the same day Sept. 8, 1908 very near 

 the maximum, were combined into an additional normal place and 

 incorporated into the observation equations, and the resulting solution 

 was satisfactory. These different solutions are given here: 



The curious behaviour of these elements in the successive solutions 

 is due to the preliminary elements in each case being not sufficiently 

 close approximations to allow the second order differentials to be 

 neglected, and also to the fact, and this also influenced the choice of the 

 preliminary values, that there were no observations near the peak of 

 the curve while the others were so situated as to abnormally influence 

 the least squares solutions. 



However it was not felt desirable as was done in the third solution 

 to combine the Ottawa measures with those from other observatories, 

 especially in view of the high residuals given by some of the latter, 

 and it was decided to secure further observations here around the 

 peak and on the descending branch of the curve to enable a more 



