62 THE HAMILTON ASSOCIATION. 
warriors, clad in brass, should go forth to battle. The religion of 
ancient Etruria was almost a worship of electricity. Centuries 
passed away, but the observations of Thales was never lost, and at 
length, at the opening of the 17th century, an Englishman named 
Gilbert made his name famous by a series of discoveries, yet they 
were so meagre as to make little advancement. Otis Guericke, a 
Prussian, invented the first machine by which electricity could be 
readily produced. He placed a globe of sulphur on an axis to be 
turned by the hand of the operator, while with the other he applied 
a cloth to the sulphur to produce the necessary friction. It was a 
rude, imperfect machine, but it made a great revelation in the 
science. Electricity, which had hithertofore been known only in its 
feeble forms, was now given out in sharp sparks, and displayed a 
thousand curious properties. Sometimes it attracted objects— 
sometimes repelled them. It seemed at times to exert a kind of 
volition. The weather affected it sensibly, dampness dissolved its 
strength ; it was capable, too, of influencing bodies at a considerable 
distance. Yet the 17th century glided away with its fierce religious 
wars and its wonderful voyages and discoveries, while little progress 
was made in the knowledge of electricity ; but in the next century 
electricity sprang at once into startling importance. Hawkesbee 
invented the glass electrical machine, and in 1730 Stephen Gray 
made a course of experiments that unfolded the leading principles 
of the science. Dufaye suspended himself with a silken cord, thus 
insulating himself, and was then charged with electricity. He 
presented his hand to his companion, half doubting the truth of his 
speculations, when a brilliant spark shot from one philosopher to 
the other, and filled both with an equal surprise. Not long after 
Prof. Musschenbroek discovered the layden jar. He had been 
endeavoring to enclose electricity in a safe receptacle from which it 
could not escape, except with his permission, and at length he 
succeeded in imprisoning the genii in a glass vessel partly filled with 
water. Suddenly he formed a connection between the two surfaces 
of the jar. The imprisoned electricity sprang through his body and 
shook him with a wild convulsion. Novelty added its terror ; his 
imagination was filled with an indefinite alarm. He shrank from 
the glass bottle as if it was tenanted by an evil spirit. Yet the shock 
of the layden vial soon became the favorite of court. It was exhib- 
