66 LOCALIZED ELECTRIZATION. 



when once an imi^ulse has been given to it.^ The following is a 

 description. 



This battery, of small dimensions, is contained in a handsome 

 box, divided into an upper and a lower part. The lower part 

 receives the liquid required to charge the battery. In the 

 upper part, a tablet of open work receives the extremities of 400 

 cylindrical elements. These elements are contained one within 

 another in pairs, one of brass in one of zinc, and are separated by 

 a slight porous tube, rendering each pair equivalent to a galvanic 

 couple. The liquid surrounds them on all siies, within and with- 

 out, and descends along the sides when the battery is in action. 



Between the lid, which is closed by a glass, and the space oc- 

 cupied by the battery, is placed the mechanism for intermissions. 

 On the right are the knobs that govern this raeclianism. The 

 movement is furnished by a fly-wheel, started by a rack C. 

 The rapid intermissions are produced by the vibrations of a spring, 

 struck by the fly-wheel. The slow intermissions are produced by 

 means of two toothed wheels, also guided by the fly-wheel, and 

 acting by means of pegs upon a lever arranged for the purpose. 

 Each wheel produces a different intermission ; and one or other of 

 them is put in action by the play of a slide, worked by drawing 

 out the stop A. 



On the left are the binding screws, N P, for fixing the con- 

 ductors. For the continuous current, the knob D must be turned 

 until it is stopped. The knob 13, which may be turned more 

 or less up to its point of arrest, serves to graduate, with perfect 

 regularity, the electro-rnotor force of the current. 



The exciting liquid having been poured into the lower compart- 

 ment, the elements are immersed by pressing upon the knob E. 

 After a few minutes, they may be raised to their former position. 



The pile is charged with common vinegar, or with pyroligneous 

 acid, pure or diluted, or with glacial acetic acid, in the proportion 

 of about ten grammes to the half litre of water, or even with salt 

 and water. 



If it be desired to carry the apparatus about, the liquid must be 

 emptied out ; and, this done, the battery will continue in action for 

 a whole day, without a sensible diminution of force. 



[Foveaux's portaMc battery. — M. Eoveaux, of the firm of Messrs. Weiss 

 and Co., has recently designed and constructed a portable battery, which 

 surpasses all others with which I am acquainted for efficiency of action, com- 

 pactness consistent with efficiency, and freedom from the annoyances which 

 too often attach to batteries of which smallness of bulk is an important 

 condition. This battery is formed of fifty pairs of Smee's elements, packed 



' This instrument is made by tiie inventor, M. A. Alph. Mathieu, mechanician. 



