DIVISION II. DETAILS _of the Effects produced by the Respiration of_ NITROUS OXIDE _upon different Individuals, furnished by Themselves_. 1. Detail of Mr. J. W. Tobin 497 2. —— of Mr. W. Clayfield 502 3. Letter from Dr. Kinglake 503 4. Detail of Mr. Southey 507 5. Letter from Dr. Roget 509 6. Letter from Mr. James Thomson 512 7. Detail of Mr. Coleridge 516 8. —— of Mr. Wedgwood 518 9. —— of Mr. G. Burnet 520 10. —— of Mr. T. Pople 521 11. —— of Mr. Hammick 522 12. —— of Dr. Blake 524 13. —— of Mr. Wanfey 525 14. —— of Mr. Rickman 526 15. —— of Mr. Lovell Edgworth 527 16. —— of Mr. G. Bedford 528 17. —— of Miss Ryland 530 18. Letter from Mr. M. M. Coates 530 DIVISION III. _Abstracts from additional Details—Observations on the effects of_ NITROUS OXIDE, _by_ Dr. BEDDOES—_Conclusion_. 1. Abstracts from additional details 533 2. Of the effects of Nitrous Oxide on delicate females 537 3. Observations on the effects of Nitrous Oxide by Dr. BEDDOES 541 4. Conclusion 548 APPENDIX. No. I. Of the effects of Nitrous Oxide on Vegetables 561 No. II. Table of the Weight and Composition of the combinations of Nitrogene 566 No. III. Additional Observations 567 No. IV. Description of a Mercurial Airholder, and Breathing Machine, by Mr. W. CLAYFIELD. 573 No. V. Proposals for the Preservation of Accidental Observations in Medicine. By Dr. BEDDOES. 577 INTRODUCTION. In consequence of the discovery of the respirability and extraordinary effects of nitrous oxide, or the dephlogisticated nitrous gas of Dr. Priestley, made in April 1799, in a manner to be particularly described hereafter,[1] I was induced to carry on the following investigation concerning its composition, properties, combinations, and mode of operation on living beings. [1] A short account of this discovery has been given in Dr. Beddoes’s Notice of some Observations made at the Pneumatic Institution, and in Mr. Nicholson’s Phil. Journal for May and December 1799.