174 



SCIENCE 



[N. S. Vol. XSXIV. No. 867 



OXYGEN 



As animadverted, ninety-four years 

 after the discovery of nitrous oxide and 

 oxygen by Priestley, they were first used 

 in combination for anestlietic purposes. 

 Although Andrews published accounts of 

 several cases, in which, by mixing oxygen 

 with nitrous oxide, he had obtained a 

 more satisfactory form of anesthesia than 

 with nitrous oxide alone, his observations 

 failed to attract the attention they de- 

 served. Ten years later (1878) Paul Bert 

 drew further attention to this form of an- 

 esthesia. Hewitt-" stated previous to the 

 completion of the work reported this morn- 

 ing, that the most recent and best develop- 

 ment in modern anesthetics is the combina- 

 tion of oxygen with nitrous oxide whereby 

 a non-asphyxial and safe form of anes- 

 thesia may be produced. The results of a 

 long series of experiments with various 

 anesthetics and different mixtures caused 

 Gwathmey to say "Oxygen is indicated 

 with every anesthetic and at all times. 

 The longer the anesthesia, the more urgent 

 is the call for oxygen by the blood." The 

 importance of the quality of the oxygen is 

 apparent. 



At the present time, there are the fol- 

 lowing methods of preparation and manu- 

 facture of oxygen:-' (1) heating chlorates; 

 (2) heating chlorates with various sub- 

 stances; (3) from hypochlorites and reac- 

 tion of chlorine and water; (4) heating 

 sulphuric acid or sulphates; (5) heating 

 various solids and mixtures (MnO,, 

 CuB^Oj, etc.) ; (6) combvistion of solid 

 mixtures (chlorates with combustible ma- 

 terial, alkaline peroxides with hydrated 

 salts, etc.) ; (7) reaction of peroxides 

 (oxone) with water and aqueous solu- 

 tions; (8) by electrolysis of water; (9) 



=* " AnEBsthetics, " The Macmillan Co. 

 " Baskerville and Stevenson, J. Ind. and Eng. 

 Chem., 3, ill. 



from the air by means of mei'cury, cu- 

 prous chloride, barium dioxide, man- 

 ganates, plumbates, or living matter, 

 or by dialysis or absorption ; and (10) from 

 liquid air. 



Oxygen that is to be used in anesthesia 

 should contain at least 95 per cent. 0, upon 

 the dry basis. We found that the pyro- 

 gallate method is the most convenient 

 method to employ and most satisfactory, 

 provided Hempel's-^ precautions to pre- 

 vent the production of carbon monoxide 

 are taken. =^ 



Analyses, by our methods, of oxygen on 

 the American market gave the following 

 results : 



CONCLUSIONS 



I realize the danger of a mere chemist 

 making an excursion into the field of med- 

 icine, but the extremely venturous one, if 

 he has luck, may be swept by the rocks of 

 which he knows little. I ventured in, as I 

 was unhampered by tradition, and I have 

 done enough in this field to make me take 

 a theoretical plunge. 



Modern studies in physiology have un- 

 questionably shown that the animal body 

 exists to a great extent by virtue of the chem- 

 ical and physical changes going on within 

 it. I know of no valid reason for assuming 



^ Hempel, ' ' Gas Analysis, ' ' English translation 

 by Dennis, 1906, p. 149. 



=° Commercial oxygen as supplied in the trade 

 has been quite thoroughly investigated by the 

 speaker and Stevenson, loo. cit. 



