12G REPORT— 1 801'. 



best, so narrow as to he comparatively valueless. In fact, Mr. Broughton Lad 

 seen but one form of oxygen inhalation. The author next stated that the influence 

 of oxygen by inhalation was modified — (1) by dilution of the oxygen, (2) by dilu- 

 tion of the blood, (.3) by the activity of the oxygen, (4) bj^ the presence or absence 

 in the blood of bodies which stop combination. On the point of dilution of oxygen, 

 Dr. Richardson stated that a certain measure of dilution was requu-ed, not because 

 the body consumed too quicldy in pure oxygen, but because neutral oxygen would 

 not combine vsdtli the carbon of the blood imless it were distributed. In atmo- 

 spheric air the dilution is just sufficient to sustain healthy combination; at 60° F. 

 the quantity of oxygen may be increased in amount to three parts of the gas to 

 two of nitrogen, and may be absorbed. Beyond this, the combining power is 

 reduced, and oxygen is not absorbed. Hence animals die in the gas as it approaches 

 the pure state ; they die not by a narcotic process, but by a process of negation. 

 On the point of dilution of the blood, the author said that blood possessing a spe- 

 cific gi'avity of 10.55 seemed to have most steady power in absorbing oxygen as it 

 existed in common aii' ; by changing the quantity of water in the blood, imtil 

 the blood is brought to a specific gravity of 1060, the absoi-ption of oxygen can 

 be raised to a maximum; but when the specific gravity is more than 1060, the 

 absorption declines. Below 10.55 the absorption steadily declines in proportion 

 to the reduction. In respect to the activity of the oxygen, the most differing re- 

 sults are obtained, according to the activity. If the oxygen be made fi-esh from 

 chlorate of potassa, even in the piu'e form it sustains life, and the activity of the 

 functions is increased ; if electric sparks are passed through the gas, or if the 

 gas be heated to 100°, the same is the fact. On the other hand, if the gas is ex- 

 posed to ammonia, to decomposing animal matter, or even to living animals over 

 and over again, it loses its activity, and no longer combines with the blood. 

 Alcohol, chloroform, opium, and certain alkaline products fomied in the blood in 

 diseases prevent the absorption of oxygen, and death not uncommonly takes place 

 from this cause. Great increase of water does the same. After this description, 

 Dr. Richardson added that the question had often been put, whether the inhalation 

 of oxygen could be usefully applied in the treatment of disease. Priestly, Beddoes, 

 Hill, and many of those who lived when oxygen was first discovered, had formed 

 the most sanguine expectations on this point ; they saw before them an elixir, 

 if not the elixir vitaj. Chaptal, in spe;ikiug of the effects of oxygen in consump- 

 tion, said of it, " It raises hope, but, alas ! it merely spreads flowers to the tomb." 

 Since then various opinions of the extremest kind have been expressed, the differ- 

 ences having arisen from the entire want of order that has been associated with the 

 inquiry. One man has used pure oxygen, the other diluted; the one active, the 

 other negative oxygen. The one has given the gas to anaemic people, whose blood 

 is sm-charged with water ; the other to diabetic or choleraic persons, whose blood 

 is of high specific gravity ; the one has given it heated, the other at the tempera- 

 ture of the day. If even a stick of phosphorus were exposed to oxygen under such 

 varying conditions, the phenomena obtained would be as variable as those that 

 have been registered in physic regarding oxygen as a remedy. The difficidties of 

 arrivino- at uniform results have been almost insurmountable from another cause — 

 that of obtaining oxygen in a ready fonn for inhalation. Fortunately, this diffi- 

 culty was now removed. The discovery by jMr. Bobbins of a mode of evohing 

 oxygen by acting on peroxide of barium and liichromate of potassa with dUute sul- 

 phuric acid, had given the author the opportunity of inventing a little apparatus 

 for inhaling oxygen, which could be carried an-ywhere and used at a moment's 

 notice. In conclusion, Dr. Richardson remarked that his object in bringing for- 

 ward this short communication was to invite medical men to a method of research 

 which promised much, and which now might be earned on with certahity of result 

 and uniformity of experience. 



On the Physiological Effects of Tobacco. By Dr. B. W. Eichaedson. 



The author began by saying that, without being a devotee to tobacco, he had 

 for many years past smoked. He did not come before the Section biassed in any 

 degree, as' his remarks would prove ; he came simply as a man of science, who had 

 tried to comprehend the facts of the whole question, and he should put these facts 



ward clearly, fairly, and free fi'oni technicalities. 



