10 CATALOGUE OF NEWTON PAPERS. 



9. Fragments on Opticks. 



10. Optical experiments. 



11. Figure and description of a sheep's eye. Printed by 

 Brewster i. 420. 



12. Speculations as to the constitution of matter and the nature 

 of the action of heat. 



XIY. MISCELLANEOUS COPIES OF LETTERS AND PAPERS. 



1. Copies of Letters from Leibnitz, Slusius, &c. to Oldenburgh. 



2. Copies of various Mathematical papers by Tschirnhausen, 

 Leibnitz, Slusius, &c. 



3. "Sur la Cubature du coin Spherique" par M. de Lagny. 



4. Fragments on Mathematical subjects by Cassini, Craig, and 

 Morland. 



XV. PAPERS ON FINDING THE LONGITUDE AT SEA. 



1. Various proposals for finding the Longitude at Sea. 



2. Several drafts of a Report by Newton to the Lords of the 

 Admiralty on the different projects for determining the Longitude 

 at Sea. 



3. Draft of a letter by Newton on the same subject. 



4. Two shorter drafts of the same letter. 



