DEC 16 1896 
TRANSACTIONS 
OF THE 
AMERICAN PHILOSOPHICAL SOCIETY. 
ARTICLE I. 
A NEW METHOD OF DETERMINING THE GENERAL PERTURBATIONS OF 
THE MINOR PLANETS. 
BY WILLIAM McKNIGHT RITTER, M.A. 
Read before the American Philosophical Society, February 28, 1896. 
PREFACE. 
In determining the general perturbations of the minor planets the principal diffi- 
culty arises from the large eccentricities and inclinations of these bodies. Methods 
that are applicable to the major planets fail when applied to the minor planets on 
account of want of convergence of the series. For a long time astronomers had to be 
content with finding what are called the special perturbations of these bodies. And 
it was not until the brilliant researches of HANSEN on this subject that serious hopes 
were entertained of being able to find also the general perturbations of the minor 
planets. HANSEN’s mode of treatment differs entirely from those that had been pre- 
viously employed. Instead of determining the perturbations of the rectangular or 
polar coérdinates, or determining the variations of the elements of the orbit, he regards 
these elements as constant and finds what may be termed the perturbation of the 
time. The publication of his work, in which this new mode of treatment is given, 
entitled Auseinandersetzung einer zweckmiissigen Methode zur Berechnung der absoluten 
A. P. S—VOL. XIX. A 
