Nikola Tesla Books
IN SEARCH OF NIKOLA TESLA possibilities. Two years later, as Tesla joined the polytechnic, Gramme's motor was shown at the Vienna Exhibition. It was then realized that not only could the device be used to generate electricity but, if supplied with external, electrical power, it would act as a motor and could then be used to drive machines. Faced with this miraculous new invention the teenage student was far from impressed. To begin with, Tesla pointed to the commutator or mechanical connection used to conduct electricity between the fixed and moving parts of the Gramme motor. Nikola argued with his professor that the machine was inefficient and lost power through sparking at the commutator when run at high speed. For his part the perceptive Professor Poeschl issued Tesla a challenge which was to preoccupy him over the next two years. If Gramme's machine was so poor, then could the student invent a better one? Tesla took up the glove Poeschl had thrown down and replied that he would devise a machine that worked with alternating, in place of direct, current. Prague University replaced Graz Polytechnic and the teenager grew into a tall and strikingly handsome young man. His confidence seems to have developed about this time and after leaving university he Tesla during his student days at Gratz, 1875-78. 61
