December 27, 1894] 



NA TURE 



20: 



NOTES. 



Prof. George Forbes, F.R.S., who has for the last 

 three years been engaged on the utilisation of Niagara Falls, 

 has, we understand, just returned to this country from the 

 United States, the construction stage of the work being 

 now completed. The close of the three years of Prof. Forbes's 

 connection with the great work at Niagara Falls, which marks 

 the change from the period of design and construction to the 

 ■period of commercial activity in the existence of the Niagara 

 ■Falls Power Company, forms a fitting opportunity for express- 

 ing the sense of gratification that all Englishmen, and the 

 scientific world in particular, must feel in having had one of their 



evolved a system which for completeness, adaptability, and 

 security against breakdowns, had not been dreamt of before. 

 The adoption of the alternating current before its value was 

 fully realised by others, the initiation of the world in the use of a 

 lower frequency than any that has hitherto been employed, 

 and the remarkable confirmation of the foresight as to the 

 economy of large transformers at high electric pressure, even 

 at the low frequency employed, that has been established, are 

 matters for congratulation. Although for fdller particulars of 

 the system and apparatus employed, we must refer our readers 

 to a previous account (Nature, vol. xlix. p. 4S2), we may 

 draw attention to the method by which Prof. Forbes met one of 

 the most troublesome questions in connection with the design of 



Fig. 



countrymen chosen to undertake the important and difHcult 

 liities of electrical consulting engineer to an undertaking of 

 uch magnitude. The manner in which those duties have been 

 discharged, and the pioneer services which Prof. Forbes has 

 rendered them in respect of the work, have, we are in 

 a position to say, received most gratifying testimony and 

 cordial acknowledgment from his Company, who recognise 

 in Prof. Forbes the scientific attainment, combined with 

 independence of thought and action, which have been 

 invaluable throughout the stage of operations now com- 

 pleted. Few realise the many novel conditions that have 

 had to be met at Niagara Falls. But by dint of years 

 of study of the many problems presented, Prof. Forbes has 



NO .1313, VOL. 51] 



the 5000-horse power generators (Fig. l), arising in consequence 

 of some requirements of the turbine designers — viz. the securing 

 of a certain necessary momentum of the revolving part of the 

 dynamo, without increasing the weight to be supported by the 

 hydraulic piston in the turbine above a certain limit. The diffi- 

 culty was met by fixing the armature, and revolving the field- 

 magnet, formed of a nickel steel ring with the oole-pieces pointing 

 radially inwards, outside, the ring, or yoke, and the pole-pieces 

 being supported by a bell-shaped cover fixed rigidly to the top 

 of the vertical shaft from the turbine, the shaft being supported 

 by bearings in the interior of the fixed armature. The fore- 

 seen ability to convert the alternating current into continuous 

 current, and the low frequency into high frequency, which is 



