302 ANNUAL OF SCIENTIFIC DISCOVERT. 



PHYSIOLOGICAL EFFECTS OF TOBACCO-SMOKING. 



At the last meeting of the British Association, 1862, Dr. Smith 

 presented an able paper, in which he adduced experiments showing 

 that, while tobacco-smoking causes a large increase in the rate of pul- 

 sation of some persons, in others no increase occurs ; and hence that 

 there is a diversity in the mode of action of this substance, as there is in 

 the admitted good or evil effects upon the body. The following are the 

 details of one of his experiments. The individual operated on was 

 made to prepare himself by sitting absolutely still until the pulse 

 stood at an average of 74.5 beats a minute. He then commenced to 

 smoke a pipe, and, during the first five minutes of smoking, the effects 

 were comparatively slight ; the pulse, however, increased in firmness 

 paid fulness, and stood at an average of 78.8 per minute. During 

 the next fourteen minutes the frequency of the pulse was 87, 88, 94, 

 <>S, 102, 102, 105, 105, 104, 105, 105, 107, 107, 110, and there was an 

 increased sense of warmth, together with slight perspiration on the 

 brow. Smoking was now stopped, and, during the next minute, the 

 pulse rose to 112; but it then began steadily to decline, till, at the 

 end of half an hour from the commencement of the smoking, it was 

 at 88.91. For more than two hours it remained above the natural 

 average of frequency and force. Dr. Smith assigns the time of 10 

 p. M. as the proper one for making experiments on the action of to- 

 bacco, and adds that no food should be taken for four hours previous- 

 ly. He considers that to literary men, on whom tobacco may be 

 found to produce this kind of stimulant effect, it would be an effective 

 substitute for the wine which they so frequently take to assist them in 

 brain-work which is done late at night ; but, when the body is of full 

 habit, it must lead to disturbed sleep, and may produce apoplexy. 



ADDITIONAL RESEARCHES ON THE SO-CALLED SPONTANEOUS 



GENERATION. 



Pasteur in his researches on fermentation has brought forward ex- 

 perimental evidence to show that this process depends upon the pres- 

 ence of minute organisms in the fermenting fluid, and that the source 

 of all such organisms is the atmosphere. In support of this opinion 

 he asserts that when a fluid containing organic matter in solution is 

 put into a flask and " boiled two or three minutes," and supplied 

 only with air which has been filtered by passing through a tube 

 heated to redness, and the flask is then hermetically sealed, no fer- 

 mentation takes place, no organisms are formed, and that the contents 

 remain indefinitely without change. But if the same solution is ex- 

 posed to the air in its ordinary condition, it becomes filled with vari- 

 ous living forms. Out of a large number of experiments prepared 

 in the manner above described, he has not known one to give a differ- 

 ent result from that mentioned. He further states that if the neck 

 of the flask is drawn out into a very slender curved tube of several 

 inches in length, the contents boiled, and then allowed to cool with- 

 out the end of the tube being closed, so that the air enters at the 

 ordinary temperature, and has free access to the interior of the 

 flask, even then DO fermentation takes place, and no organisms ap- 

 pear. His explanation of this is, that the air which enters first 



