The chronological history of the employment of anaesthetics in modern times may be recapitulated as follows :Sir Humphry Davy's declaration with regard to nitrous oxide gas: Amongst its other properties it has that of destroying physical pain. Davy did not convey the idea, or expound the principle, that the inhalation of narcotic and stimulating vapours would destroy pain, but confined his remarks to the nitrous oxide; nor did he imagine the production of a state of unconsciousness. Sir H. Davy, April 11th, 1799.

Anaesthetic state produced by vital magnetism, or nervous fluid. Removal of the entire breast for cancer. Dr. Jules Cloquet, Paris, April 12th, 1829.

Anaesthetic state induced by the inhalation of alcoholic fumes. Reduction of hip-joint. Dr. Collyer, Louisiana, Dec. 1839.

Anaesthetic state induced by Dr. Collyer on a child twenty-two months old. Entire removal of the globe of the eye for fungus haematodes. Dr. Rich, Bangor, Maine, Dec. 1841.

Anaesthetic state induced by the inhalation of narcotic and stimulating vapours. Extraction of a tooth from Miss Allen. Dr. Collyer, Philadelphia, April, 1843.

Publication of the "Psychography," wherein at pages 26, 27, 28, 30, 32, 35, and 36, the inhalation of narcotic and stimulating vapours is stated to produce the unconscious or anaesthetic state. Author (Dr. Collyer), Philadelphia, May, 1843.

Report of lectures (vide Lancet) in Liverpool Mail and Standard. Dr. Collyer, Liverpool, Oct. 1843.

Protoxide of nitrogen. Extraction of tooth. Horace Wells, Hartford, Dec. 1844.

Publication in Boston Medical and Surgical Journal of the administration of opium and ether. Dr. E. R. Smilie, Boston, June, 1846.

Inhalation of sulphuric ether. Wm. T. G. Morton, Boston, Sept. 30th, 1846.

Experiments with chloroform on animals. Flourens, Paris, March, 1847.

Anaesthesia produced by chloric ether. Sir William Lawrence, London June, 1847.

Anaesthesia produced by the inhalation of chloroform. Dr. James Simpson, Edinburgh, Nov. 1847.

Anaesthesia by amylene. Dr. John Snow, London, June, 1857.

Bichloride of methylene. Dr. Benj. W. Richardson, London, June, 1867.