PBEFACE TO VOLUME I. 



THE present volume of the Collected Works of the late Professor 

 JOHN COUCH ADAMS contains all the original papers which were published 

 by him during his lifetime, extending from 1844 (when he was 

 25 years of age) to 1890. They consist of about 50 Astronomical Papers 

 which were for the most part printed in the Memoirs or Monthly Notices 

 of the Royal Astronomical Society and 11 Papers on Pure Mathematics. 

 Besides these there are many papers on various branches of Astronomy 

 which were left in an incomplete state among Professor Adams' manuscripts. 

 These are being prepared for publication by Professor Sampson. 



There is also a great quantity of unpublished work in an incomplete 

 state on Legendre's and Laplace's Coefficients and on Terrestrial Magnetism 

 which was taken up from time to time extending over a period of 40 

 years, but no part of which has been published except a short paper 

 (No. 60) on Legendre's Coefficients. It is hoped that a considerable 

 portion of this unpublished work may shortly be brought into shape for 

 publication, and that it will form the continuation of these Collected 



Works. 



Since the Appendix to Paper 19 (p. 124 of this volume) was 

 printed, more exact expressions of the coefficients for Jupiter's Satellites 

 II, III and IV have been found among Professor Adams' unpublished 

 papers. Thus in forming the Tables for Satellite II, in addition to the 

 terms -2 S> 5 sin (II- A,,)- l s '5 sin (n-A in ) given on p. 118 of this volume, 

 another term + s '127 sin (II-A IT ) was employed in the calculation for the 



