E'xperiments with Grove’s Battery. 391 
SOeDInws 
i 
Table constructed from the Curve. 
; Inches. 
4 Batteryalone = = = = 5.20 
20 | Onewmile /+) es = wees 885 
Two miles oS eS Baee omy ROR 
Three * r nm ie - 1.Bhes 
Four. ‘i « sen Se ELSE 
Five “ ‘ - ~ - 105° 
— Six * a) “a - 92 
30. Seven “ “ ” . - .80 
f Hight * - - “ melt 
i Nine a % - - 64 
; Pets." . i" ” - 57 
} Twenty “ * - i 4s 7D 
of, Thirty “ ay ee Pea BO 
re orty «* - gat ae ee C4 
Fifty. “ etna 098 
i a 
During the previous summer I made the following experiments 
upon a line of thirty-three miles, of number 17 copper wire, with 
a battery of fifty pairs. In this case, I — * = -stagap eee 
with weights, with which I was enabled to weigh with a good 
degree of accuracy the greater magnetic ee ee” 
yet sufficiently approximating the recent ee °°. ciemee e 
w in question. sie aca 
’ 
