Part 9 (1/2)

APPENDIX

I NOTE ON THE CONTRIBUTIONS OF FLEEMING JENKIN TO ELECTRICAL AND ENGINEERING SCIENCE BY SIR WILLIAM THOMSON, FRS, LL D, ETC, ETC

IN the beginning of the year 1859 ue (the first British University Professor of Engineering), Lewis Gordon, at that ti and cable laying, ca subh the for practical use on the first Atlantic cable, and which had actually done service upon it, during the six weeks of its successful working between Valencia and Newfoundland

As soon as he had seen so of what I had in hand, he said toed in our works at Birkenhead' Fleeraphed for, and appeared nextthe whole day in an our lifelong acquaintance I was htness and ability, but with his resolution to understand everything spoken of, to see if possible thoroughly through every difficult question, and (no if about this!) to slur over nothing I soon found that thoroughness of honesty was as strongly engrained in the scientific as in the moral side of his character

In the first week of our acquaintance, the electric telegraph and, particularly, submarine cables, and the , and using them, formed naturally the chief subject of our conversations and discussions; as it was in fact the practical object of Jenkin's visit to ow; but not much of the week had passed before I found hienerally, and full of intelligent eagerness on many particular questions of dynaow to Birkenhead 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 conductor, and the insulating resistance and specific inductive capacity of its gutta-percha coating, in the factory, in various stages of manufacture; and he was the very first to introduce systerand system of absolute measurement founded in Germany by Gauss and Weber The immense value of this step, if only in respect to the electric telegraph, is amply appreciated by all who re of the history of subenerally how raph (Electric)' in the last volume of the old edition of the 'Encyclopaedia Britannica,' which was published about the year 1861, we find on record that Jenkin's measureutta-percha, and of the gutta-percha with Chatterton's co the insulation of the Red Sea cable of 1859, are given as the only results in the way of absolutematerial which had then been made These remarks are prefaced in the 'Encyclopaedia' article by the following stateht in future to be accepted in any departraphic business which has not this definite character; although it is only within the last year that convenient instru, in absolute measure, have been introduced at all, and the whole system of absolute measure is still almost unknown to practical electricians'

A particular result of great i is referred to as follows in the 'Encyclopaedia' article: 'The i results thus stated in absolute measure is illustrated by the circumstance, that the writer has been able at once to coraph, with his own previous deductions fro its manufacture in 1857, and with Weber's measurements of the specific resistance of copper' It has now becoland; twenty-two years later by Germany, the country of its birth; and by France and Italy, and all the other countries of Europe and America-practically the whole scientific world-at the Electrical Congress in Paris in the years 1882 and 1884

An ies published in the 'Transactions of the Royal Society' for June 19, 1862, under the title 'Experinals through subh various lengths of one cable, by Flee Jenkin, Esq, communicated by C Wheatstone, Esq, FRS,' contains an account of a large part of Jenkin's experi the years 1859 and 1860 This paper is called Part I Part II alas never appeared, but so that it would have included we can see fro ominous statement which I find near the end of Part I: 'Froth 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 deterutta-percha, or of the gutta-percha and Chatterton's co the insulation of the cable, on which he experimented This was the very first true measurement of the specific inductive capacity of a dielectric which had been made after the discovery by Faraday of the existence of the property, and his prilass, shellac, and sulphur; and at the time when Jenkin made his measurements the existence of specific inductive capacity was either unknown, or ignored, or denied, by alinal deterht out under the auspices of the British association Committee on Electrical Standards, is due to experimental work by Jenkin, described in a paper, 'Experi No IV of the appendix to the Report presented by the Co of 1867 No other determination, so far as I know, of this important element of electric measure to be proud of in respect to Jenkin's fame as a scientific and practical electrician that the microfarad whichall use is his

The British association unit of electrical resistance, on which was founded the first practical approximation to absolute ely due to Jenkin's zeal as one of the originators, and persevering energy as a working member, of the first Electrical Standards Co practical standards, founded on the absolute system, which led to the unit non as the British association ohm, was chiefly perforreat practical benefit which has resulted from the experimental and scientific work of the Coe measure due to Jenkin's zeal and perseverance as secretary, and as editor of the volume of Collected Reports of the work of the Coht years, from 1861 till 1869 The volume of Reports included Jenkin's Cantor Lectures of January, 1866, 'On Subh which the practical applications of the scientific principles for which he had worked so devotedly for eight years beca profession

Jenkin's scientific activity continued without abatement to the end For the last two years of his life he was much occupied with a new mode of electric locoave the naenuity in carrying out the nuements essential to the project, up to the very last days of his work in life He had completed almost every detail of the realisation of the syste at Glynde, in Sussex, four netisman's elementary series in 1873, marked a new departure in the exposition of electricity, as the first text-book containing a systeurated by the British association Committee on Electrical Standards In 1883 the seventh edition was published, after there had already appeared two foreign editions, one in Italian and the other in Gerh not nust these es,' written by him for the ninth edition of the 'Encyclopaedia Britannica,' and afterwards republished as a separate treatise in 1876; and a paper 'On the Practical Application of Reciprocal Figures to the Calculation of Strains in Frah, 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 published in the 'Transactions,' vol xxviii (187678), for which he arded the Keith Gold Medal This paper was a continuation of the subject treated in 'Reulaux's Mechanis the value of that work, supplied the elements required to constitute froy and doing work

II NOTE ON THE WORK OF FLEEMING JENKIN IN CONNECTION WITH SANITARY REFORM BY LT COL ALEXANDER FERGUSSON

IT was, I believe, during the autu Jenkin the first inkling of an idea, not the least in importance of the ular rapidity, took root, and under his careful fostering expanded into a scheme the fruits of which have been of the utmost value to his fellow-citizens and others

The phrase which afterwards suggested itself, and came into use, 'Healthy houses,' expresses very happily the drift of this scheme, and the ultimate object that Jenkin had in view

In the summer of that year there had been much talk, and some newspaper correspondence, on the subject of the unsatisfactory condition of ards their sanitary state One gentlee and expensive house he had bought in the West-end of Edinburgh, fresh fro, and the steps to be taken to remedy the evils, the effects of which were but too apparent, obviously demanded the expenditure of ent proprietor himself and the professional experts he had to call in, and, it is needless to add, much money There came also, from the poorer parts of the town, the cry that inpeople were built anyhow that the dictates of a narrow econoested to the speculative and irresponsible builder The horrors of as called the 'Sandwich systeht It is sufficient to say, generally, that this particular practice of the builder consists in placing in a block of workmen's houses, to save space and money, the water cisterns of one flat, directly under the sanitary appliances of the other, and so on to the top of a house of several storeys It is easy to conceive the aboe of the upper floors begins to penetrate to the drinking water below The picture was a hideous one, apart from the well-known fact that a whole class of diseases is habitually spread by conta discussion had been carried on in the colureater part of that e of towns, had been dealt with by several writers well inforst others, Professor Jenkin hi, who now occupies the chair of Civil Engineering in Edinburgh Many of the truths then advanced had been recently discussed at aof the British association

It hile such topics were attracting attention that Fleeence of the loss that friends of theirs had sustained in the deaths of several of their children from causes that could be traced up to the unsanitary condition of their house Sympathy took the practical forate the chance of such calamities; and, I am permitted to say, the result of a home-talk on this subject was an earnest appeal to the head of the house to turn his scientific knowledge to account in some way that should make people's homes more healthy, and their children's lives hts in this direction And the scheme which I shall endeavour briefly to sketch out was the result

The obvious remedy for a faulty house is to call in a skilful expert, architect or engineer, ill doubtless point out by est a remedy; but, as remarked by Professor Jenkin, 'it has not been the practice for leading engineers to advise individuals about their house arrangee outlay is in contemplation' A point of very considerable importance in such a case as that now supposed

The problereat body of the citizens sound professional advice concerning their houses, such as had hitherto been only obtainable at great cost-but 'with due regard to econoes of co-operation are patent to all Everyone can understand how, if a sufficient nues that are not within their reach, for a arding a dwelling-house was a palpable advantage; but within the reach of co prescribed as the cure for a poor Infirood plans Jenkin's scheme was simple in the extreme, and consisted in _combination_ and a s physician of the day reat nuathered in a hospital, although he could not practically visit them in their own houses, so the siroup will enable the leading engineer to give them the benefit of his advice'

But it was his opinion that only 'continual supervision could secure the householder froer due to defects in sanitary appliances' He had in his eye a case precisely sie in one of his first lectures, afterwards repeated frequently, conveys the essence of Professor Jenkin's theory, as well as a graceful acknowledgment of the source froous case occurred to him,' he said, 'in the ”Steam Users'