Figure 37. — Calibration of two Clark cells. From Philosophical Transactions of 

 the Royal Society of London, 1874, vol. 164, p. 14, fig. 6. 



under certain conditions. The possibilities inherent 

 in such a technique drew the attention of many 

 inventors to the new phenomenon. 



The development of steam as a prime mover for 

 factory machinery during the Industrial Revolution 

 and the rapid development of steam locomotives and 

 steamboats during the 30's and 40's of the 19th 

 century made inventors dream of applying the new 

 force of electricity in a similar way to manufacturing 

 and commerce. Before this dream could be realized, 

 however, certain prerequisites had to be fulfilled. 

 A means of applying electrical energy to produce a 

 mechanical force had to be found, a switch had to he 

 devised to make it possible to apply the mechanical 



force at the right time in the cycle of the motor, and 

 an appropriate recipient for the mechanical force 

 had to be discovered. The invention that enabled 

 man to convert electrical energy into a mechanical 

 force was the electromagnet. The commutator was 

 the switch that determined when the force was applied, 

 and the recipient of the force was the armature. In 

 addition, there had to be devised the most efficient 

 arrangement of electromagnets, commutator, and 

 armature for the production of rotational motion. 

 Actually our modern motor did not develop from the 

 efforts of this period, but such attempts are nonetheless 

 interesting for they reveal the state of electrical 

 technology in the middle of the 19th century. 



PAPER 28: DEVELOPMENT OF ELECTRICAL TECHNOLOGY IN THE 19TH CENTURY: I 



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