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PROCEEDINGS OF 
but to repeat the names of this scientific host, would fill a volume. Confining the 
inquiry to our own country would still transcend the limits of an address. Omit¬ 
ting, then, the whole range of hyperphysical knowledge, I shall confine my in¬ 
quiries to the various improvements and discoveries made by our countrymen in 
the inductive sciences. It is said we have not contributed, in this respect, our 
share to the mighty mass of accumulated knowledge of the world. But it could 
not be expected that a nation whoso existence as such is less than a century 
could, in that brief period, have equalled the discoveries of thousands of years. 
Without boasting, however, of our achievements, an impartial examination will 
show that our countrymen have greatly contributed to the modern improvements 
and discoveries in the various departments of the inductive sciences. 
And, first, of electricity. This has been cultivated with the greatest success in 
our country, from the time when Franklin with his kite drew down electricity 
from the thunder cloud, to that when Henry showed the electrical currents produced 
by the distant lightning discharge. In Franklin’s day the idea prevailed that there 
w T ere two kinds of electricity, one produced by rubbing vitreous substances, the 
other by the friction of resinous bodies. Franklin’s theory of one electric fluid in 
all bodies, disturbed in its equilibrium by friction, and thus accumulating in one 
and deserting the other, maintains its ground, still capable of explaining the facts 
elicited in the progress of modern discovery. Franklin believed that electricity 
and lightning were the same, and proceeded to the proof. He made the perilous 
experiment, by exploring the air with a kite, and drawing down from the thunder 
cloud the lightning’s discharge upon his own person. The bold philosopher re¬ 
ceived unharmed the shock of the electric fluid, more fortunate than others who 
have fallen victims to less daring experiments. The world was delighted with the 
discoveries of the great American, and for a time electricity was called Franklin- 
ism on the continent of Europe ; but Franklin was born here, and the name was 
not adopted in England. While Franklin made experiments, Kinnerslev exhibit¬ 
ed and illustrated them, and also rediscovered the seemingly opposite electricities of 
glass and resin. Franklin’s lightning rod is gradually surmounting the many dif¬ 
ficulties with which it contended, as experience attests the greater safety of houses 
protected by the rod, properly mounted, whilst the British attempt to substitute 
balls for points has failed. This question, as to powder magazines, has lately ex¬ 
cited much controversy. Should a rod be attached to the magazine, or should it 
be placed upon a post at some distance ? This question has been solved by Henry. 
When an electrical discharge passes from one body to another, the electricity in 
all the bodies in the neighborhood is affected. Henry magnetized a needle in a 
long conductor, by the discharge from a cloud, more than a mile from the con¬ 
ductor. If a discharge passes down a rod, attached to a powder house, may it 
not cause a spark to pass from one receptacle for powder to another, and thus in¬ 
flame the whole? The electrical plenum, which Henry supposed, is no doubt dis¬ 
turbed, and to great distances; but the effect diminishes with the distance. If 
all the principal conductors about a building can be connected with a lightning 
rod, there is no danger of a discharge ; for it is only in leaving or entering a con¬ 
ductor that electricity produces heating effects : but if not, the rod is safer at a 
moderate distance from the building. The rate at which electricity moved was 
another of the experiments of Franklin. A wire was led over a great extent of 
ground, and a discharge passed through it. No interval could be perceived be¬ 
tween the time of the spark passing to and from the wire at the two ends. Not 
