1152 The Galvanic Battery. [No. 108. 



accelerated by employing pasteboard instead of ox gullet partitions, a 

 suggestion due to Dr. Q'Shaughnessy of Calcutta. The details are as 

 follow; — 



1 . The dimensions having been decided upon, a piece of sheet copper of 

 [Fig. II. a.] the proper size, is to be formed into a rectangular cell, the 

 junctions of the side pieces and bottom being soldered with hard brass 

 solder. As the power of a Battery is considerably augmented by bring- 

 ing the opposite surfaces of copper as near as possible to each otherj 

 the edge and bottom pieces of the cell are usually very small in propor- 

 tion to its sides. When the latter are 14" or 15" square, the former 

 may conveniently be made half an inch in breadth. A small connecting 

 tube, about an inch in depth, or a connecting screw soldered at the 

 top of one of the edge pieces completes the copper element. 



2. The partition cases are made of common strong brown pasteboard, 

 [Fig. II. c] two pieces of this being laid together, and their edges or three 

 sides compressed between strips of teak wood, half an inch in breadth, 

 l-8th in thickness, the length being regulated by the dimensions of the 

 copper cell into which the case should slide easily. Screw nails of 

 copper, if such are to be obtained, but otherwise of iron, passed through 

 the teak binders and the pasteboards, render the case water-tight at 

 the edges, and complete its manufacture. 



The zinc element consists of a piece of the sheet zinc of commerce 

 [Fig. II. b.] (spelter) of such a size, as to admit of its readily passing in- 

 side the pasteboard case, and rounded off, as shown in the sketch. 

 A thick copper wire is soldered to it, to facilitate the connections 

 throughout the Battery, by dipping into the mercurial cups above described. 



A Battery of this rectangular form was used in the destruction of 

 the barque " Equitable," having side pieces 14" x 14", edge and bottom 

 ditto 14" X A"> pasteboard cases \Z\" x 13i", and zinc plates 

 12" X 12", the number of cells employed being 12. 



Section II. — Of the Excili7ig Solutions for the Battery — their nature^ 

 preparation, and proportions. 



It has been found by experience that strong chemical action on the 

 zinc of a Battery, with the interposition of a good conducting solution 

 between the zinc and the copper, are the conditions by which powerful 

 galvanic action is insured. 



