SECTION I. MATHEMATICS. 5 



11. Revision of the Principia. Notes relating to Calculation of 

 orbits of Comets. 



12. Additions and Corrections to 1st Edition of the Principia. 



13. Additions and Corrections to the 2nd Edition of the 

 Principia. 



14. Observations and Calculations about Comets. 



15. Draft of part of the Preface to the 1st Edition of the 

 Principia. Not quite as printed, in part fuller. 



1 6. Preface and Preparations for 3rd Edition of the Principia. 



17. Very rough fragments relating to the Principia. 



18. Miscellaneous Calculations. 



19. Corrections to 1st Edition of the Principia (terribly damaged 

 by fire). 



20. Dr Halley's account of the Principia given to K. James II. 



IX. PAPERS CONNECTED WITH THE PRINCIPIA. 

 B. Lunar Theory. 



1. Papers on the Lunar Theory found in interleaved copy of 

 1st Edition of Principia (damaged by fire). 



2. Propositions prepared to be used in the Lunar Theory 

 (greatly damaged by fire). 



3. Fragments on the Lunar Theory (greatly damaged by fire). 



4. Propositions in the Lunar Theory, found on loose sheets placed 

 at the end of the interleaved copy of the 1st Edition of the 

 Principia. 



These were probably intended to be employed in a 2nd Edition, 

 but the design was not carried out. 



5. Notes on the law of change of the Moon's variation according 

 to the change of the Sun's distance; and on the mutual action of 

 Jupiter and Saturn. 



6. Unarranged fragments connected with points of the Lunar 

 Theory. 



7. On change of the variation in an excentric orbit, and on the 

 motion of the Moon's Apogee. 



8. A list of Propositions in the Lunar Theory, prepared for a 

 2nd Edition of the Principia, but not used. 



