556 



of Galvani gives sufficient indications of the electric current without 

 the use of that instrument. ^ 



The general results obtained from these experiments are the fol- 

 lowing. 



In the first place, the intensity and duration of the muscular cur- 

 rent is independent of the nature of the gas in which the muscular 

 pile is immersed. Secondly, it is altogether independent of the ce- 

 rebro-spinal portion of the nervous system. Thirdly, the circum- 

 stances which exercise a marked influence on its intensity are the 

 conditions of the respiratory and circulatory systems. Fourthly, those 

 poisons which seem to act directly on the nervous system, such as hj- 

 drocyanic acid, morphia and strychnine, have no influence on the ner- 

 vous current. Fifthly, sulphuretted hydrogen has a decided influence 

 in diminishing the intensity of the muscular current. Sixthly, the in- 

 tensity of this current in frogs varies according to the temperature in 

 which the frogs have been kept for a certain time during life ; a result 

 which, of course, is not obtainable with animals which do not take 

 the temperature of the surrounding medium. Lastly, the intensity 

 of the muscular current in animals increases in proportion to the 

 rank they occupy in the scale of beings ; and on the other hand, its 

 duration after death is exactly in an inverse ratio to its original in- 

 tensity. The author concludes by stating his belief, that the pro- 

 perty of the muscles immediately connected with -their electric cur- 

 rents, is identical with that which was long ago denominated by 

 Haller irritability^ but which is at present more usually designated 

 by the term contractility. He ascribes the development of this 

 muscular electricity to the chemical actions which are attendant on 

 the process of nutrition of the muscles, and result from the contact 

 of arterial blood with the muscular fibre. He conceives that in the 

 natural state of the muscle, the two electricities thus evolved neu- 

 tralise each other at the same points at which they are generated ; 

 while in the muscular pile contrived by the author, a portion of this 

 electricity is put into circulation in the same mann,er as happens in 

 a pile composed of acid and alkali separated from one another by a 

 simply conducting body. 



June 19, 1845. 

 RICHARD OWEN, Esq., V.P., in the Chair. 



" On the Connexion between the Winds of the St. Lawrence and 

 the Movements of the Barometer." By William Kelly, M.D., Sur- 

 geon R.N., attached to the Naval Surveying Party on the River St. 

 Lawrence. Communicated by Captain Beaufort, R.N., F.R.S. 



The author adduces a great number of observations which are in 

 opposition to the generally received opinion, that the mercury in the 

 barometer has always a tendency to fall when the wind is strong. 

 During a period of fifteen years passed in the Gulf and River St. 



