34 Use of the Galvanic Battery in Blasting. 
was blasting single blocks; the effect was ‘much better than wha 
the fuze was used, in consequence of the clay being more firmly ~ 4 
driven round the wires than it would be round the larger surface — 
of the fuze. @2ndly, I selected two large blocks nearly in line; 
the first block was 43 feet from the battery; the second block — 
113 feet from the battery, and the blocks consequently were 70 _ 
feet from each other. On dipping the plates, the explosions took | 
place in quick succession; the battery consisted of 30 pairs of 
4-inch plates. 3rdly, I wished to try the effect of a simultaneous 
explosion of two blasts on a very large. block firmly tied together 
by rivets. ‘The positive wires of each cartridge were fastened to 
the positive connecting wire, and in like manner the negative 
wire. The effects of this simultaneous explosion were very | 
good; the exciting liquor being weak, the connecting wires were 
shortened to 98 feet. Ath, To amuse some friends, I exploded, © 
some powder in one of the youd depth 10 feet; length of wire 
210 feet; 40 pairs of plates, with old exciting Sener :—the ex- 
periment succeeded to the delight of all; a large eel was killed 
by the blow-up. Ihave no doubt but wild fowl will yet be killed 
by means of shells placed at low water on the banks where they 
feed ; and by means of long connecting wires, the shells can be 
made to explode simultaneously among the birds. 
1 find that 10 pairs of 4-inch plates free from oxide and charged 
with the following exciting liquor—water, 64 quarts; sulph 
acid of commerce, 44 ounces; nitrous acid, 44 ounces ; will igni t 
powder with a wire LOL feet long. 20 pairs of plates ignited. pow 
der at the distance of 353 feet. I tried to repeat this experim 
but did not succeed, though the plates were only three times i ime. 
mersed in the acid, nak only for about two seconds each time: «1 
tried the same battery at 268 feet, and did not succeed. The — 
plates were then well washed, and fresh exciting liquor made : 
the experiment again failed ; the plates were quite inactive. The 
next day I tried the saine plates and the same exciting liquor, and 
succeeded at 268 feet. From this it seems impossible to say 
how many pairs of plates would be required to produce uniform 
effects at long distances. I suspect that the zine plates do not act 
Se in producing the electricity, which causes this variation. 
have liked very much to have tried the conducting 
fe of different sized wires, but had not an apponnlttes oe 
getting them here, 
