s field, to
prove his calculations by shooting at a mark. On account of his
expertness in his calculations, and of their ineffectual efforts to
discover the use he was making of quicksilver, the shop-hands nicknamed
him 'quicksilver Bob.'

"Mr. Messersmith and Mr. Christian Isch were employed by the Government
to make and repair the arms for the troops; and on several occasions
guards were stationed at their shops to watch and see that the workmen
were constantly employed during whole nights and on Sunday, to prevent
any delay. The workmen had so much reliance and confidence in
'quicksilver Bob's' judgment and mechanical skill, that every suggestion
he would make as to the alteration of a gun, or any additional ornament
that he would design, was invariably adopted by common consent.

"In the summer of 1779, Robert Fulton evinced an extraordinary fondness
for inventions. He was a frequent visitor at Mr. Messersmith's and Mr.
Fenno's gunsmith shops, almost daily, and endeavored to manufacture a
small air-gun."

Among the acquaintances of Robert Fulton at this time was a young man,
about eighteen years of age, named Christopher Gumpf, who used
frequently to accompany his father in his fishing excursions on the
Conestoga. Mr. Gumpf, Sen., being an experienced angler, readily
consented to allow Robert to join himself and his son in these
expeditions, and made the two boys earn their pleasure by pushing the
boat about the stream, as he desired to move from point to point. As the
means of propulsion was simply a pole, the labor was very severe, and
Robert soon became tired of it. Not wishing, however, to give up his
pleasant fishing trips, he determined to devise some means of lightening
the labor.

"He absented himself a week, having gone to Little Britain township to
spend a few days at his aunt's; and while there he planned and completed
a small working model of a fishing boat, with paddle-wheels. On leaving
his aunt's, he placed the model in the garret, with a request that it
should not be destroyed. Many years afterward, that simple model was the
attraction of friends, and became, instead of lumber in the garret, an
ornament in the aunt's parlor, who prized it highly. That model was the
result of Robert's fishing excursions with Christopher Gumpf; and when
he returned from his aunt's he told Christopher that he must make a set
of paddles to work at the sides of the boat, to be operated by a double
crank, and then the