260 ANNUAL OF SCIENTIFIC DISCOVERT. 



in rapid succession, exactly as if yeast, and not blood, had been directly 

 poured into the vessels. 



It seems likely that in this case a series of decompositions take place within 

 the blood, which give rise to other ferments. The well-known experiment 

 related in Pringle's work on Army Diseases appears to tally with the result 

 of our own experiments. 



(In order to prove the influence of putrid emanations, even at a distance, on 

 the chemical phenomena of life, he plunged a thread into the yolk of a rotten 

 egg, and then suspended it in ajar containing the yolk of another egg, and 

 under these circumstances decomposition took place with far greater rapidity 

 than usual.) 



We, therefore, perceive that all this series of phenomena hold intimate 

 connection with that mysterious chemical process known under the name of 

 catalysis. The theory of fermentation is at present so imperfectly known, 

 and organic chemistry has in this respect made, as yet, so little progress, 

 that it would hardly be fair to reproach medicine with its deficiencies on this 

 point. There exists a whole series of diseases which evidently result from 

 the chemical actions which take place within the body. It is, therefore, 

 chemistry alone which, in its future progress, can teach us the physiological 

 laws which embrace this particular branch of medicine. 



CATALYSIS AND CONTACT ACTION. 



It is well known that a super-saturated solution of crystallized sulphate of 

 soda, exposed to the air, crystallizes suddenly when touched by a glass rod, 

 but that it does not crystallize when this rod is heated to one hundred degrees 

 Centigrade. Lcewel attributes this action to thecn'r adherent to the rod; and 

 it then becomes an interesting question, whether the air alone suffices for the 

 production of the result, or some peculiar quality contained in the air ? 

 The. latter supposition seems the most probable, since it is not caused by air 

 which has been filtered through cotton contained in a tube, nor by air which 

 has passed through a properly arranged series of flasks, connected by tubes 

 of glass. Air thus agitated, or heated by friction, may be brought in con- 

 tact with the super-saturated solution, under the form of a continued current, 

 without determining the crystallization, which commences immediately in 

 the presence of normal air. Loewel attributes the modification produced by 

 the air to the friction produced in his mode of experiment, and a recent 

 experiment of his pupil Him proves that it is so. 



The air thus rendered passive by Lcewel is called adynamic air. Him has 

 observed that the air is rendered completely adynamic when it escapes after 

 compression in the form of a jet from the receiver in which it was confined. 

 After this compression it can be directed with impunity into a solution of 

 sulphate of soda saturated by heat in a closed vessel. On the contrary, the 

 solution solidifies instantaneously if, by the same tube, and without any 

 derangement of the apparatus, some bubbles of ordinary air are allowed to 

 pass into the solution. Here, then, is an action purely mechanical which 

 replaces the action of heat, a remarkable example of the correlation of force, 

 which raises a crowd of questions, and which leads to the inquiry, if an 

 identical composition of the air should always have an identical action upon 

 a living being; if air rendered adynamic by a storm is not found in differ- 

 ent conditions, in relation to organized beings, than air long undisturbed? 

 This brings to mind that Schrceder and Busch have shown that fermentation 



