359 



current ceases to pass there is contraction, for then the influence 

 which antagonized contraction is removed. When, on the other 

 hand, the direct current passes, there is contraction at the beginning 

 of the current, for the influence of the current upon the nerve-current 

 is one which favours contraction ; when the direct current ceases to 

 pass, there is no contraction, for then the influence is no longer one 

 which favours contraction. 



(c) In the third period that of single contraction the muscular 

 movements resulting from the action of a galvanic current upon 

 nerve are at first sight somewhat perplexing; but with a little 

 thought, it may be seen that the same key will apply to their 

 interpretation. 



If, as has just been mentioned, contraction attends upon the 

 beginning of the direct current because this current is found to 

 favour contraction, it is not difficult to find a reason which will ex- 

 plain in some degree, not only why in the period of double contrac- 

 tion the strongest contraction is at the beginning of the direct 

 current, but also why in the first part of the period now under con- 

 sideration that of single contraction contraction should continue 

 to attend upon the direct current after it has ceased to attend upon 

 the inverse current. Nor are the apparent irregularities in contrac- 

 tion, the " voltaic alternatives," entirely inexplicable ; for it may be 

 that these seeming irregularities this apparent shifting of contrac- 

 tion from the beginning of the direct to the beginning of the inverse 

 current, and so backwards and forwards once and again maybe 

 nothing more than the natural consequence of the changes which at 

 this time have taken place, and are taking place, in the direction of 

 the nerve-current. 



III. " Letter from Lord HOWARD DE WALDEN AND SEAFORD, 

 Her Majesty's Minister at Brussels, to Lord JOHN RUS- 

 SELL, on a recent severe Thunder-storm in Belgium." 

 Communicated by the Right Hon. Lord JOHN RUSSELL. 



The writer states that the thunder-storm burst between seven 

 and eight o'clock at night on Sunday the 19th of February, and 

 was accompanied by an unusually heavy fall of snow throughout 

 Belgium. Twelve churches were struck almost simultaneously, 



