284 LOCALIZED ELECTRIZATION. 



I am about to lay down. I must therefore ask, above all, for an 

 attentive perusal of the following lines. 



In order to put the apparatus in action, the regulator of the 

 armature, N, must be turned from left to right, until the soft iron 

 no longer comes in contact with the magnet during its rotary 

 motion. 



If the employment of a rapid current is indicated, the regulator 

 of the intermissions, D, must be turned from right to left, until it 

 reaches its point of arrest. If, on the contrary, it is necessary to 

 produce distant intermissions, the same regulator, D, must be 

 turned in the opposite direction, and stopped when the needle of 

 the indicator points to the number of intermissions which it is 

 desired to obtain for each revolution of the large wheel. The 

 handle, turned from left to right, should always be moved very 

 quietly, making perhaps two revolutions in a second. 



In order to graduate the currents, it is sufficient to remember 

 that when the stem R is pushed within the ap})aratus the current 

 is at its minimum. The graduation of this stem in millimetres 

 renders it possible to divide the electric doses in fractions, in 

 proportion to the excitability of the organs, and to the require- 

 ments of therapeutics. 



If the region operated upon be highly excitable, or, in other 

 terms, if it is necessary to administer very feeble doses, the arma- 

 ture must be moved farther away from the magnet, by turning the 

 regulator N from left to right. 



If it be desired to experiment upon the frog, the armature is 

 moved away from the magnet as far as possible, and at the same 

 time the current is cut off from the commutator, by turning back, 

 from right to left, the small screw at the base of the spring S. 



After having thus diminished the power of the apparatus, 

 infinitely small doses can be measured with the same exactitude as 

 powerful ones. 



Lastly, the knob T of the commutator of the coils must be 

 turned from right to left, when we wish to bring the current of 

 the primary coil to the knobs P and P', to which the conductors 

 of the rheophores are fixed. We turn, on the contrary, the knob 

 T from left to right, in order to bring to the rheophores the 

 current of the secondary coil. 



§ V. — Recapitulation. 

 The description of the properties possessed by my magneto- 

 faradic apparatus has shown that its invention constituted a real 

 progress, not only with regard to its applications in medicine, but 

 also from a purely physical aspect. 



