162 



SCIENCE 



[N. S. Vol. XXXIV. No. 867 



corded his own sensations and the behav- 

 ior of others after they had inhaled it. 



In 1805, Dr. Warren, of Boston, used 

 "sulphuric ether" on a patient suffering 

 with phthisis, and the year following it 

 was used in attacks of asthma; but Fara- 

 day, in 1818, was the first to recognize its 

 value as an anesthetic. 



Chloroform was discovered in 1831 in- 

 dependently by Liebig, Soubeiran and 

 Guthrie. It is reported in the American 

 Journal of Science for January, 1832, 

 that Dr. Ives, of New Haven, used chloro- 

 form in surgery. 



In 1828, Girardin read a paper describ- 

 ing surgical anesthesia by means of in- 

 haled gases, bi;t the honor of the discovery 

 of surgical anesthesia has been claimed 

 with more or less acrimonious partizan- 

 sliip for four others, namely. Long, of Jef- 

 ferson, Ga., who anesthetized a patient 

 with ether in 1841; Wells, of Hartford, 

 Conn., who used nitrous oxide in dentistry 

 in 1844; Morton, a pupil of Wells, used 

 ether instead at the suggestion of Jackson, 

 a chemist, who later claimed to be the 

 real discoverer. Simpson, in 1847, first used 

 ether in midwifery and later chloroform, 

 whose anesthetic properties had been 

 previously described by Flourens. In 

 1868, Andrews, of Chicago, called atten- 

 tion to the use of oxygen with nitrous 

 oxide to produce a non-asphyxial form of 

 anesthesia. In 1906, Brown, of Cleve- 

 land, used a warmed mixture of nitroiis 

 oxide and oxygen, followed by ether and 

 chloroform, with great success; and in 

 1909 Gwathmey, of New York, first used 

 warm moist vapors of pulmonary anes- 

 thetics. 



1 shall not recount the historical data 

 which have to do with other anesthetics, a 

 list of which I have published in the 

 American Druggist, as my remarks this 

 morning will be limited to nitrous oxide, 



ether and chloroform, and these few facts — 

 the results obtained from careful unbiased 

 investigation of the literature and other 

 forms of evidence — are given without 

 elaboration or argument. 



The speaker knows of no satisfactory 

 basis of classification of anesthetics, hence 

 those that are to be considered will be 

 taken up in chronological order. 



NITROUS OXIDE 



In 1772 Priestley first prepared nitrous 

 oxide by reducing NO with moist iron 

 filings. In 1793 Deiman and others pre- 

 pared the gas by heating NH4NO3, essen- 

 tially the commercial process for its manu- 

 facture to-day. It is usually carried out 

 by heating mixed salts, as NaNO, and 

 (NHJ,SO„ NaNOs and NH.Cl, eta." 



Commercial nitrous oxide is apt to con- 

 tain these impurities: CI2, NO, NO2, 

 HNO3, NH3, HCl, CO,, O2, No and rare 

 gases of the air. It is usually purified by 

 passing through solutions of sodium hy- 

 droxide, ferrous sulphate and sulphuric 

 acid. Further purification may be ac- 

 complished by the formation of a hydrate^ 

 (NoO, 6H„0) below 0° C. and heating this 

 hydrate, with fractional condensation* and 

 subsequent fractional distillation. 



Beyond the absence of disturbing im- 

 purities, the improved methods of the use 

 of nitrous oxide for anesthetic purposes 

 demand a knowledge of the approximate 

 content of nitrous oxide in the commer- 

 cial product, as will become apparent 

 later, hence a method for its determina- 

 tion is desirable. Various methods have 

 been proposed, for instance, decomposition 

 into Nj and O2, burning with hydrogen, 

 explosion with hydrogen, combustion of 



" The subject is thoroughly covered in a paper 

 by the speaker and Stevenson, J. Ind. and Eng^ 

 Cheni., 3, No. 8. 



^Villard, Compt. rend., 1894, 118, 1096. 



* Stolzenberg, Ber., 43, 1708. 



