62 



LOCALIZED ELECTRIZATION 



speaks very highly, when he has had occasion to make use of the interrnpted 

 galvanic current in the treatment of infantile paralysis, the variety he terms 

 " organic," and to which Duchenne has given the designation " fatty atrophic 

 paralysis of infancy" {yaralysie atrophv/ue graisseuse de Tenfance). The 

 following is Dr. Hammond's description of this instrument : — 



" It consists of a series of elements formed of plates of perforated zinc 

 and copper, as shown in fig. 19. These plates are soldered together, the 

 copper being bent over at the sides, the zinc laid ujion it, and the two 

 securely fastened. A thin piece of wood is then jilaced between the plates, 

 to jirevent their being pressed together. The elements rest upon a plate of 

 hard rubber, and are kejot in place by four hard rubber rods. Two other 

 plates of hard rubber, having each a large hole in the centre, and four holes 

 for the rods, rest on the top. These are kept in place by pins which pass 

 through holes in the rods. The whole is hung to an iron or brass support 

 as shown in the figure, and a saucer underneath catches the vinegar used to 

 set the instrument in action. 



" To arrange the apparatus, an element with a copper wire soldered to 

 the copper plate, is placed uiion the lower piece of hard rubber; upon the 

 element, a piece of flannel, and so on. The elements are so placed that 

 the copper is always below. The last element has a i^iece of copper wire 

 soldered to the zinc plate. Insulated wii'es are used to connect the poles 

 with the electrodes. 



" To set the apparatus in action, strong vinegar is poured upon the top. 

 It passes through the elements, and moistens the flarmel. If the plates 



Fig. 19 — TIammnnd's columnar batteiy. 



