440 



SCIENCE 



[N. S. Vol. XLIX. No. 1271 



simplest way to solve the problem of lofty 

 ascents would be by means of oxygen appa- 

 ratus. The Germans evidently made use 

 of such apparatus, for it was found in the 

 wreck of one of the German planes shot 

 down over London. The British also had 

 such apparatus, but it was difficult to manu- 

 facture, wasteful in operation, and in other 

 respects left much to be desired. In fact 

 the devising of such apparatus and its 

 adaptation to the peculiar requirements of 

 the humanr wearer are a problem which can 

 be solved only by the close cooperation of 

 a physiologist and a mechanical engineer. 

 Mr. W. B. Gibbs, of the Bureau of Mines, 

 with whom I had cooperated in developing 

 mine rescue oxygen apparatus, took up this 

 problem and produced a device which 

 should prove valuable. Unfortunately the 

 common tendency to favor ideas and ap- 

 paratus coming to us from Europe oper- 

 ated against the adoption of the better 

 American device. 



It is doubtful however whether any appa- 

 ratus of this sort will ever quite take the 

 place of physical vigor and capacity to re- 

 sist oxygen deficiency on the part of the 

 aviator himself. Imagine him, when fight- 

 ing for his life above the clouds, handi- 

 capped by goggles over his eyes, wireless 

 telephone receivers on his ears, a, combined 

 telephone transmitter and oxygen inhaler 

 over his mouth, and a padded helmet on his 

 head! 



The importance of determining the avia- 

 tor's inherent power of resistance to oxy- 

 gen deficiency, if he is to be even for a few 

 moments without an oxygen inlialer, is 

 demonstrated by the results of the routine 

 examinations made with the rebreathing 

 apparatus in the laboratory. These results 

 show that 15 to 20 per cent, of all the men 

 who pass an ordinary medical examination 

 are unfit to ascend to the altitudes now re- 

 quired of every military aviator. On the 



other hand these tests pick out a small 

 group of 5 to 10 per cent, who, ^vithout ap- 

 parent immediate physical deterioration, 

 withstand oxygen deficiency corresponding 

 to altitudes of 20,000 feet or more. 



It is particularly interesting to note that 

 when the rebreathing test is pushed beyond 

 the limit that the man can endure, be it the 

 equivalent of only 10,000 or 25,000, two 

 different physiological types with all gra- 

 dations between them are revealed. The 

 fainting tj'pe collapses from circulatory 

 failure and requires an hour or two to re- 

 cover. Often the heart appears distinctly 

 dilated. The other and better ty^pe, on the 

 contrary, goes to the equivalent of a tre- 

 mendous altitude on the rebreathing appa- 

 ratus and loses consciousness, becoming 

 glassy-eyed and more or less rigid, but 

 without fainting. When normal air is ad- 

 ministered such men quicklj' recover. 



Perhaps I ought to say at least a few 

 words regarding the other aspects of the 

 work at Mineola: for example the valuable 

 psychological investigations and the con- 

 troversy over the rotation tests, which has 

 figured so largely in our medical journals 

 of late. It seemed best, however, to confine 

 myself this evening to my own special field. 

 Nevertheless I can not suppress a public 

 expression here of my sjonpathy for the 

 brave and able scientific men in the psycho- 

 logical group at Mineola, who insisted on 

 investigating the validity of the rotation 

 tests. I am sure that you will feel as I do, 

 when I tell you that they were threatened 

 with punishmnet for insubordination when 

 they refused to recognize that a regulation 

 of the army, which prescribes the duration 

 of nystagmus after the rotation test, neces- 

 sarily makes this a physiological fact. 



I would gladly devote a few minutes also 

 to pointing out some of the lessons to be 

 drawn from the rather unusuallj^ good op- 

 portunities which fell to my lot to observe 



