60 SELLERS — TRANSML^SION OF ENERGY BY ELECTRICITY. [Feb. 3, 



than ever before undertaken. This non-competing company, how- 

 ever, a few years after executed much of the work required. 



A majority of the Commissioners favored the transmission by direct 

 current, but as they were not asked to express an opinion in that 

 direction, there was no report made as to the character of the elec- 

 tric current if electrical transmission should be decided upon ; but 

 a unanimous opinion was given as to the advantage of a unit of 5000 

 horse power for each turbine in the power house, working under a 

 head of not over 140 feet fall, at a speed of 250 revolutions per 

 minute, which was feasible with turbines that could be made of 

 high efficiency. 



The speed recommended was thought to be what would be accept- 

 able to makers of dynamos, whether for alternate or direct current. 

 It is noteworthy, as indicative of the state of the art in 1891, that 

 out of many electrical schemes proposed all but two were based on 

 the generation of the direct current, with the consensus of opinion 

 in favor of the gramme ring as the type of armature. 



While waiting for the reports of competing engineers to come in, 

 between July of 1890 and the first of January, 1891, I had time 

 to visit Italy, France, Switzerland and England, where I collected 

 information as to the efficiency of the several modes of transmit- 

 ting power at that time in vogue. I could find but one example 

 in France of power for factory purposes transmitted by direct cur- 

 rent, in which case a turbine was located in a rugged mountainous 

 district, quite inaccessible in winter. The water-wheel, of perhaps 

 200 horse power, drove a direct-current dynamo, from which the 

 current was conveyed by overhead conductors to a direct-current 

 motor in a paper-mill, in a small town, a distance of five miles. 

 This paper-mill had been operated without profit by steam, but was 

 said to be profitable under the new conditions. The machinery in 

 this case was started and stopped at the turbine by means of tele- 

 phone communication from the mill to the men in charge at the 

 water power. I visited many interesting plants for the transmission 

 of power by water under pressure and by compressed air, and saw 

 the most important electrical developments for lighting purposes, 

 some by the alternate current, but most by the use of the direct 

 current. 



In Paris I made a careful examination of the Popp system of 

 compressed air with great interest, on account of the highly favor- 

 able reports that had readied me and the claims as to efficiency 



