528 



slowly altered blood does not seem to lose its virtues by having passed 

 into a state of ice. 



In the frog, the return of irritability is favoured by connexion with 

 the general circulation. A frog was secured with its hind legs in a 

 freezing mixture, the brain and spinal cord having been removed. In 

 a few minutes the legs were frozen stiff, and had lost all irritability. 

 After being frozen half an hour they were thawed. Irritability re- 

 turned. 



Nerves, too, like muscles, lose their excitability when frozen, arid, 

 like them, may regain it on being thawed if they have not been 

 frozen too long. I have always found a greater difficulty in recover- 

 ing nerves than muscles. 



One very curious thing is this, that, as Eckard states*, when 

 nerves are frozen, the muscles to which they are distributed are 

 thrown into contractions ; and yet when muscles themselves are 

 frozen, there is not only no tetanic spasm, but not necessarily even 

 the smallest quivering. 



VIII. " On the alleged Sugar-forming Function of the Liver." 

 By FREDERICK W. PAVY, M.D. Communicated by Dr. 

 SHARPEY, Sec. R.S. Received June 21, 1860. 



(Abstract.) 



This communication is an abridgement of a paper bearing the 

 same title presented by the author to the Royal Society in 1858, 

 with some additional matter, since disclosed by his experimental in- 

 vestigations. 



He first shows, by analyses, that although the blood collected 

 from the right side of the heart after death, as was formerly done, 

 affords an abundant indication of the presence of sugar, yet that when 

 it is removed from the same part by catheterism during life, it is 

 found to contain but a trace of the saccharine principle. Inferences, 

 therefore, that have been drawn of the ante-mortem state from post- 

 mortem examinations must be abandoned as erroneous. 



The heart excised instantaneously after sudden killing, contains 

 blood as free from sugar as it is during life. 



* Eckard, Zeitschr. f. Rat. Med. vol. x. (1851).' 



