CHEMICAL SCIENCE. 227 



minutes. Dr. Smith stayed about '20 minutes, but felt very anxious to 

 get out, as his movements were made with great haste, and both mind 

 and body betrayed symj>ioms of leverish activity. The face was 

 Unshed, and the lungs acted more rapidly than usual. In fact there 

 was a burning haste to live, as if life were afraid of being put out. It 

 seems to him impossible to endure four per eent of carbonic aeid 

 for any length of time. There was a very remarkable lowering 

 of the pulse, and as this happened regularly he puts it down as the re- 

 sult of poisoning with carbonic aeid gas, and asks whether it may not 

 suggest a mode of Lowering the pulse in a fever. These experiments 

 show the great mischief that must arise from the impure, unwholesome 

 air in metalliferous mines. The men call it "thin," "poor, 1 ' "dead;" 

 the effect is slow poisoning. The explosions of gunpowder produce 

 sulphide of potassium, the effect of which is probably like that of sul- 

 phide of hydrogen, but from its acting more slowly there is distributed 

 over a long period that death which might ensue instantly, and so, in 

 chemical phrase, the effect is dissolved in health, and becomes dis- 

 ease. Gun cotton seems to promise to perform the work of blasting 

 with less injurious inlluence upon the air. In the above report, Dr. 

 Smith touches also upon various other points of practical importance. 

 He notices the purifying effect of rain upon the air, of which there 

 was such a scarcity last year. Moisture with a high temperature is 

 oppressive, but moisture with a lower temperature improves the air, 

 and he holds that cold and moisture in such amounts as those in which 

 they are found in Great Britain are capable of producing powerful 

 constitutions, and that the more watery districts of the kingdom pre- 

 sent in many instances the most healthy spots. Still, in relation to 

 ventilation he notes that " chemical action, and with it the feelings 

 demand a certain amount of warmth first and above all things. No 

 function can go on without it. You may live hours, days, or years 

 in badly ventilated places with more or less discomfort and danger, 

 but a draught of cold air may kill like a sword. In railway carriages, 

 and in houses also, the great instinct of man is first to be warm 

 enough, and he is quite right. Such a universal instinct must not be 

 sneered at." 



ON THE INHALATION OF OXYGEN GAS. 



In a paper on the above subject, read before the British Associa- 

 tion 1804, by Dr. Richardson, the well-known physiological chemist, 

 the author stated, that his experiments on the inhalation of oxygen 

 had led him to an almost precise knowledge of the condition under 

 which oxygen would most freely combine with blood. It had been 

 stated in almost every modern work on physiology that oxygen in- 

 haled in a pure form is a narcotic poison. These statements are based 

 on the researches of Mr. Braighton, in which the late Sir Ben. Brodie, 

 took part. The observations of Mr. Braighton, in so far as the re- 

 cital of the phenomena observed by him were concerned, were strictly 

 correct ; but the inferences that had been drawn from him were nearly 

 altogether incorrect, and were, at the best, so narrow as to be com- 

 paratively valueless. In fact, Mr. Braighton had seen but one form 

 of oxygen inhalation. The author next stated that the influence of 

 oxygen in inhalation was modified 1. By dilution of the oxygen ; 2. 



