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physiological effects, inasmuch as these phenomena are the most 

 striking which animal electricity is capable of producing in common 

 with other electricities derived from different sources. 



The following experiments, in which the frog's limb was used as 

 a galvanometer (the limb of this animal being, as is well known, an 

 instrument of extreme delicacy for this purpose), seem satisfactorily 

 to establish the fact that the common actinise of our shores are 

 gifted with electrical power. 



1st. Having prepared the lower limb of a lively frog after the 

 mode described by Matteucci, by stripping off the skin, dissecting 

 out the sciatic nerve from among the muscles of the thigh, and then 

 cutting off the thigh a little above the knee, so as to leave the nerve 

 uninjured and as long as possible, the limb was laid on a small 

 piece of glass, so that the nerve hung down over its edge. The 

 pendent nerve was lowered into the water and gently brought in 

 contact with the tentacles of an expanded actinia. From the first or 

 the second, or even several, possibly no effect may result, but 

 arriving at last at one more vigorous than his neighbours, smart 

 muscular contractions follow as he grasps the nerve in his tentacles, 

 and the toes are thrown into active movement. 



2nd. The next experiment, although of precisely the same nature 

 as that first detailed, renders the effect produced on the muscles of 

 the frog's limb more striking. A large and lively frog is killed, the 

 skin is stripped off, and the viscera being removed, the body is cut 

 off about the middle ; a knife being slipped behind the lumbar 

 plexus of nerves, the pelvic bones and contiguous soft parts are cut 

 away, so that the lumbar vertebrae remain connected with the lower 

 extremities merely by the nervous cords passing to each limb. Thus 

 prepared, the limbs are laid on a thin piece of board, so that the 

 vertebrae hang over its edge dangling by the undivided nerves. The 

 piece of board is placed floating on the surface of the water in which 

 are the actiniae, and is slowly pushed over within reach of an active 

 one. Immediately that the actinia seizes the morsel thus offered to 

 it, contractions are observed to commence in the thigh, extend to the 

 calf, and soon the toes are in movement. 



3rd. In order to set aside the supposition that these muscular con- 

 tractions might be the result of chemical or mechanical irritation 

 applied to the extremities of the nerves, it became necessary to devise 



