86 DISCUSSION ON ELECTRIC TRACTION. 



conveys sufficient electricity to kill a horse, yet there is not 

 sufficient current to kill a human being." 



Mr. C. W. S. James. C.E., said he had been deeply 

 interested in the paper read, and had tried to think how far 

 the electric traction system could be applied to Hobart. A 

 few months ago he had estimated what could be done in 

 Launceston by utilising the South Esk River, and he thought 

 that there from 1,000 to 1,300 horse-power could be available. 

 In regard to Hobart, however, there was not the same power 

 available, and he believed they would require to look to 

 generated power in any electrical system introduced. He 

 thought the system could be usefully applied to carrying 

 minerals on the West Coast, and that the " overhead system '* 

 was well adapted for the streets of Hobart. 



Mr. J. Fincham, C.E., said he had followed the paper with 

 interest, but they had no reference to the length of the steep 

 grades surmounted. He believed that in any scheme for 

 electrical traction in Hobart this would be one of the 

 difficulties. He was aware that there were about 300 tram- 

 ways in America, but he had not been able to get any 

 particulars as to the grade, or whether it was equal to such a 

 grade as they had to contend with in going up Elizabeth- 

 street. 



Mr. A. W. Lawder, C.E., thought the length of grade to 

 be overcome simply resolved itself into a question of the 

 power of the accumulator. 



Mr. Eincham said that was just the difficulty the engineers 

 found. They had not been able to provide enough accumula- 

 tion to overcome a sustained strain. 



Mr. Jones, in reply, said Mr. Fincham appeared to associate 

 the " storage system " with the practical operation of electric 

 trams, but it was clearly pointed out that the " storage " up 

 to the present time was an ideal method, and that the 

 " overhead system " was the only one of practical value. 

 The main defects of the former are the limited capacity of 

 the cells, and when brought to bear on a grade of 5 per cent., 

 heat instead of current was developed, which buckled the cell 

 plates, rendering them useless ; and, again, the cells are 

 composed of lead, weighing altogether 3,5001b., which has to 

 be carried about over light as well as the heavy grades, losing 

 60 per cent, of the available efficiency. Coming to the 

 " overhead system," the question of surmounting heavy and 

 continuous grades resolves itself into a question of increased 

 power, which is always to be obtained from the central 

 station, and herein lies the great advantage the overhead 

 system has over any other. All the available energy can be 



