ld be
either to prevent a stroke by repelling the cloud beyond the striking
distance or by drawing off the electrical fire which it contained; or,
if they could not effect this they would at least conduct the electrical
matter to the earth without any injury to the building.
"It was not until the summer of 1752 that he was enabled to complete his
grand and unparalleled discovery by experiment. The plan which he had
originally proposed was, to erect, on some high tower or elevated place,
a sentry-box from which should rise a pointed iron rod, insulated by
being fixed in a cake of resin. Electrified clouds passing over this
would, he conceived, impart to it a portion of their electricity which
would be rendered evident to the senses by sparks being emitted when a
key, the knuckle, or other conductor, was presented to it. Philadelphia
at this time afforded no opportunity of trying an experiment of this
kind. While Franklin was waiting for the erection of a spire, it
occurred to him that he might have more ready access to the region of
clouds by means of a common kite. He prepared one by fastening two cross
sticks to a silk handkerchief, which would not suffer so much from the
rain as paper. To the upright stick was affixed an iron point. The
string was, as usual, of hemp, except the lower end, which was silk.
Where the hempen string terminated, a key was fastened. With this
apparatus, on the appearance of a thundergust approaching, he went out
into the commons, accompanied by his son, to whom alone he communicated
his intentions, well knowing the ridicule which, too generally for the
interest of science, awaits unsuccessful experiments in philosophy. He
placed himself under a shed, to avoid the rain; his kite was raised, a
thunder-cloud passed over it, no sign of electricity appeared. He almost
despaired of success, when suddenly he observed the loose fibres of his
string to move towards an erect position. He now presented his knuckle
to the key and received a strong spark. How exquisite must his
sensations have been at this moment! On his experiment depended the fate
of his theory. If he succeeded, his name would rank high among those who
had improved science; if he failed, he must inevitably be subjected to
the derision of mankind, or, what is worse, their pity, as a
well-meaning man, but a weak, silly projector. The anxiety with which he
looked for the result of his experiment may easily be conceived. Doubts
and despai
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