Memoir of Fleeming Jenkin

to Electrical and Engineering Science. by S

uring the six weeks of its successful working between Valencia and Newfoundland. As soon as he had seen something of what I had in hand, he said to me, 'I would like to show this to a young man of remarkable ability, at present engaged in our works at Birkenhead.' Fleeming Jenkin was accordingly telegraphed for, and appeared next morning in Glasgow. He remained for a week, spending the whole day in my class-room and

rkenhead a correspondence commenced between us, which was continued without intermission up to the last days of his life. It commenced with a well-sustained fire of letters on each side about the physical qualities of submarine cables, and the practical results attainable in the way of rapid signalling through them. Jenkin used excellently the valuable opportunities for experiment allowed him by Newall, and his partner Lewis Gordon, at their Birkenhead factory. Thus he began definite scientific investigation of the copper resistance of the con

onstituting the insulation of the Red Sea cable of 1859, are given as the only results in the way of absolute measurements of the electric resistance of an insulating material which had then been made. These remarks are prefaced in the 'Encyclopaedia' article by the following statement: 'No telegraphic testing ought in fut

re them, in the manner stated in a preceding paragraph, with his own previous deductions from the testings of the Atlantic cable during its manufacture in 1857, and with Weber's measurements of the specific resistance of copper.' It has now become universally adapted

never appeared, but something that it would have included we can see from the following ominous statement which I find near the end of Part I.: 'From this value, the electrostatical capacity per unit of length and the specific inductive capacity of the dielectric, could be determined. These points will, however, be more fully treated of in the second part of this paper.' Jenkin had in fact made a determination at Birkenhead of the specific inductive capacity of gutta-percha, or of the gutta-percha and Chatterton's compoun

periments on Capacity,' constituting No. IV. of the appendix to the Report presented by the Committee to the Dundee Meeting of 1867. No other determination, so far as I know, of this important element of

on the absolute system, which led to the unit now known as the British Association ohm, was chiefly performed by Clerk Maxwell and Jenkin. The realisation of the great practical benefit which has resulted from the experimental and scientific work of the Committee is certainly in a large measure due to Jenkin's zeal and perseverance as secretary, and as editor of the volume of Colle

is own, to which he gave the name of 'Telpherage.' He persevered with endless ingenuity in carrying out the numerous and difficult mechanical arrangements essential to the project, up to the very l

ty, as the first text-book containing a systematic application of the quantitative methods inaugurated by the British Association Committee on Electric

o the Calculation of Strains in Framework,' read before the Royal Society of Edinburgh, and published in the 'Transactions' of that Society in 1869. But perhaps the most important of all is his paper 'On the Application of Graphic Methods to the Determination of the Efficiency of Machinery,' read before the Royal Society of Edinburgh, and pub

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n in Connection with Sanitary Refo

nd