Extracts of Letters found among the Papers of Mr John Collins, relating to the Collection of Mathematical Letters published by Dr Wallis in the third volume of his Works Lists 18 letters; 1. Dr Barrow to Mr Collins ...20 July 1669 2. Dr Barrow to Mr Collins ...31 July 1669 3. Dr Barrow to Mr Collins ....20 August 1669 4. Mr Collins to Mr James Gregory....25 November 1669 5. Mr James Gregory to Mr Collins.....5 September 1670 6. Mr Collins to Mr James Gregory.....24 December 1670 7. Mr Collins to Mr Bertet......21 February 1670 8. Mr Collins to Borellius.....December 1671 9. Mr Collins to Mr Vernon.....26 December 1671 10. Mr Collins to Mr Strode ...26 July 1672 11. Mr Collins to Mr Newton...30 July 1672 12. Mr Newton to Mr Collins.....10 December 1672 13. Mr Oldenburg to Monsr. Fran. Slusius....29 January 1673 14. Paper by Mr Collins corrected by Mr Oldenburg in order to be copied and sent to Mr Tschurnham 15. Mr Collins to Mr Oldenburg to be communicated to Mr Leibnitz.....10 April 1675 16. Mr Collins to Mr Oldenburg to be sent to Mr Leibnitz.....14 June 1676 17. Mr Collins to Mr David Gregory, the brother of Mr James Gregory newly deceased.....11 August 1676 18. Mr Collins to Dr Wallis .....14 February 1676/7 1669-1677