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Triumphs of Invention and Discovery in Art and Science
Twenty-two years have passed since then, and the marvel of 1838 has become a mere everyday affair. There are some fourteen different lines of steamers, comprising more than fifty vessels, running between the United States and Europe, to say nothing of the magnificent steam fleets of the Peninsular and Oriental, the Royal West India, British and North American, Pacific, Australian, South Western, and other companies.
The employment of iron in the construction of ships, thus securing at once lightness and strength, and the invention of the screw propeller, in 1836, by Mr. J. P. Smith, a farmer at Hendon, by means of which a vessel can combine all the qualities of a first-rate sailing ship with the use of steam power, gave a great impulse to steam navigation, which is still making steady and continuous progress. From one steam vessel in 1812 the number in the kingdom has risen successively to 20 in 1820, 824 in 1840, and over 2000 in 1860. During 1858, 153 steamers were built in the United Kingdom, of which 112 were of iron. It is interesting to observe the advance in size of the steam vessels from their first introduction on the Clyde.
In the interval between 1812 and 1870 the number of steamers in the United Kingdom has increased from one to nearly three thousand; and the ocean-going steamer of 1870 is nearly six times the length of that of 1825, and seventeen times the length of the Comet, while the difference in tonnage is still greater. How Fulton or Bell would open their eyes at the sight of a vast moving city, such as the Big Ship, an eighth of a mile in length, propelled by both paddle-wheels and screw, each worked by four huge engines!
Iron Manufacture
HENRY CORT
The multifarious use of iron in our day has given its name to the age. We have got far beyond the primitive applications of that metal – every day it is supplanting some other substance, and there is no saying where the wide-spread and varied service we exact from it will stop. The invention of the steam-engine, and the improvement of manufacturing machines, would be comparatively valueless, unless we had at command a cheap and abundant supply of iron for their construction. The land is covered with a net-work of iron rails, traversed by iron steeds – gulfs and valleys are spanned by iron arches and iron tubes – huge ships of iron ride upon the deep. Even stones and bricks are being discarded for this all-useful substance, and of iron we are building houses, palaces, theatres, churches, and spacious domes. There is no end to its uses.
And yet, it is only between seventy and eighty years ago since Britain, the richest of all countries in native ore, was dependent upon others for her supply of the manufactured metal. We wanted but little iron in those days, compared with the present demand, and yet that little we could not furnish ourselves with. As much as a million and a half a-year went out of our pockets to purchase wrought iron from Sweden alone, and we were good customers to Russia as well. All the iron that our country could then produce was some 17,000 tons. The man who showed us how to turn our own ore to account, who rendered us independent of all other countries for our supply, and made us the great purveyors of wrought iron to the world, who opened up to us this great source of national wealth, was Henry Cort of Gosport.
The great difficulty which he solved was how to get wrought iron out of the crude iron as it came from the smelting furnace, without using charcoal. With but a small tract of country, densely peopled, we had but a scant supply of wood at our command. The great forests which once overspread the land were gradually vanishing, partly before the spread of population and the growth of towns, and partly from the inroads made on them by the demand for timber. Formerly, the first transformation of the ore into pig iron (the crude form of the manufactured metal) was effected by means of wood; and the consumption was so great that an Act was passed in 1581 restraining its use. Soon afterwards Lord Dudley discovered that coal would answer the purpose just as well, and obtained a patent of monopoly. He reaped but little profit from his invention, however, for his iron-works were destroyed by a mob; and it was not till a century afterwards, when people got more alarmed at the growing scarcity of timber, and the increased demand for it, that the plan was generally adopted. This was one step in the right direction, but another yet remained to be made, for the manufacture was still hampered in our country by the want of wood for the second process – the conversion of crude into malleable iron, in which state alone it is fit for service.
About the year 1785, Henry Cort, iron-master, of Gosport, after many years of patient and wearisome research, of anxious thought, and indefatigable experiment, in which he spent a private fortune of some £20,000, perfected a couple of inventions of priceless value. The first was the process of converting pig iron into wrought iron by the flame of pit coal in a puddling furnace, thus dispensing with the use of charcoal, – the cost and scarcity of which had before formed such a dead weight on the trade, and placed us at such a disadvantage compared with Sweden and Russia. The second was a further process for drawing the iron into bars by means of grooved rollers. Till then, this operation had to be performed with hammer and anvil, and was very tedious and laborious. The new system not only reduced the cost and labour of producing iron to one-twentieth of what they were previously, but greatly improved the quality of the article produced.
It is not easy to estimate all that Henry Cort's inventions have done for this country. Without them we should have lost an overflowing and inexhaustible source of national wealth, and, moreover, large sums would have been taken out of the country in the purchase of wrought metal; we should never have been able to give full scope to the great mechanical inventions brought forth towards the close of the last, and the opening of the present century; we should have been debarred from taking rank as the great engineers and engine-makers for the rest of the world. The direct gain to this country from the inventions of Henry Cort, which enabled us to work up our own iron, has been calculated as equal by this time to not less than a hundred millions; and it is hardly possible to exaggerate the benefits which it has conferred. Lord Sheffield's prophecy, that the adoption of these processes would be worth more to Britain than a dozen colonies, may be said to have been fulfilled.
Like many another benefactor of his country, Cort got little good out of his invention for himself. He took out a patent for his process, and arranged with the leading iron-masters to accept a royalty of ten shillings a ton for the use of them. With a large fortune in prospect, his purse was just then exhausted by the expenses he had incurred in experiments and researches; and he had to look out for a capitalist to aid him in working the patent on his own account. As ill luck would have it, he entered into partnership with a certain Adam Jellicoe, then deputy-paymaster of the navy. Jellicoe was considered a man of substance, and a "thoroughly respectable" character. He was to advance the ready money, and to receive in return half of the profits of the trade, Cort assigning to him, by way of collateral security, his patent rights. For a year or two all went well. The patent was everywhere adopted, and Cort's own iron works drove a lucrative and growing trade. He seemed in a fair way of getting back the fortune he had spent in bringing out the inventions, doubled or trebled, as he well deserved. The respectable Jellicoe was seized with a mortal sickness: at his death his desk was filled by another, his books were examined, and it turned out that he had been robbing the government for many a year back, and was a large defaulter. Cort, of course, had nothing to do with this villany, but he had to pay the penalty of it. As Jellicoe's partner he was responsible, in those days of unlimited liability, for all Jellicoe's debts; but that was not the worst of it. The treasurer of the navy was not content to exact only the payment of Jellicoe's defalcations, as he had no doubt a right to do, but confiscated the whole of Cort's patent rights, business, and property, which would have paid the debt seven or eight times over, had it been fairly valued.
This incident has never been properly cleared up, but what glimpses of its secret passages have been obtained, seem to indicate clearly enough that poor Cort was the victim, not of one, but of two or more swindlers. To the day of his death he never could obtain a distinct account of the proceedings; and when, after his death, a Royal Commission was appointed to inquire into the matter, the treasurer of the navy and his deputy took care, a week or two before the Commission met, to indemnify each other by a joint release, and to burn their accounts for upwards of a million and a half of public money, for the application of which they were responsible, as well as all papers relating to Cort's case. When the Commission met, and the treasurer and his deputy were called before it, they refused to answer questions which would criminate themselves.
His connection with Jellicoe was, of course, the ruin of Henry Cort. He had no means of re-establishing himself in business; he was robbed of all income from his patents; and he died ruined and broken-hearted ten years after, leaving a family of nine children, without a sixpence in the world. Four of these children now survive – old, infirm, and indigent – only saved from being dependent upon parish bounty by pensions, amounting in the aggregate to £90 per annum. Well may it be said, "There should be more gratitude in our Iron Age to the children of Henry Cort."
The Electric Telegraph
I. – MR. COOKE
Of all the marvels of our time, the most marvellous is the subjugation of the electric fluid, that potent elemental force, – twin brother of the fatal lightning, – to be our submissive courier, to bear our messages from land to land, and "put a girdle round about the earth in forty minutes." The Prospero that tamed this Ariel was no individual genius, but "two single gentlemen rolled into one." The idea of employing the electric current for the conveyance of signals between distant points, can be traced pretty far back in date; but to Mr. Cooke and Professor Wheatstone is undoubtedly due the credit of having made the electric telegraph an actual and accomplished fact, and rendered it practicable for everyday uses.
Having served for a number of years as an officer in our Indian army, Mr. Cooke came back to Europe to recruit his health in the beginning of 1836, and took up his abode at Heidelberg. He found agreeable occupation for his leisure in the study of anatomy, and in the construction of anatomical models for his father's museum at Durham, where he was a professor in the university. Entirely self-taught in this delicate art, Mr. Cooke applied himself to it with characteristic ardour, and attained remarkable skill. One day he happened to witness some experiments which were made by Professor Möncke, to illustrate the feasibility of electric signalling. A current of electricity was passed through a long wire, and set a magnetic needle at the end quivering under its influence. The experiment was a very simple one, and not at all novel; but Cooke had never paid any attention to the subject before, and was much struck with what he saw. He became strongly impressed with the possibility of employing electricity in the transmission of telegraphic intelligence between distant places. From the day he witnessed the experiments in Professor Möncke's classroom, he forsook the dissecting knife, threw aside his modelling tools, and applied himself to the realization of his conception. With such ardour and devotion did he labour, and such skill and ingenuity did he bring to the work, that within three weeks he had constructed a telegraph with six wires, forming three complete metallic currents, and influencing three needles, by the varied inclination of which twenty-six different signals were designated. In that short time he had also invented the detector, by which injuries to the wires, whether from water, fracture, or contact with substances capable of diverting the current, were readily traced, and the alarum, by which notice is given at one end of the wire that a message is coming from the other. Both these contrivances were of the utmost value, – indeed, without them electric telegraphy would be impracticable, – and are still in use. Possessing more of a mechanical than a scientific genius, Mr. Cooke bestowed more of his time and ingenuity on the perfection of a telegraph to be worked by clock mechanism, set in action by the withdrawal of a detent by an electro magnet than in the completion of the electric telegraph pure and simple.
Soon after having invented his telegraph, he came over to London, and spent the rest of the year in making a variety of instruments, and in efforts to get his telegraph introduced on the Liverpool and Manchester Railway. He found an obstacle to the complete success of his mechanical telegraph, in the difficulty of transmitting to a distance sufficient electric power to work the electro magnet upon which its action depended. A friend advised him to consult Professor Wheatstone, then known to be deeply engaged in electrical experiments, with a view to telegraphy; and accordingly, an interview between them took place in February 1837.
II. – PROFESSOR WHEATSTONE
Mr. Charles Wheatstone, F.R.S., and Professor of Experimental Philosophy in King's College at the time of that interview, had made considerable advances in the scientific part of the enterprise. At the commencement of his career as a maker and seller of musical instruments in London, he was led to investigate the science of sound; and from his researches in that direction, he was led – much as Herschel was led – to devote himself to optics, and to study the philosophy of light. He was the first to point out the peculiarity of binocular vision, and to describe the stereoscope, which has since become so popular an instrument. Gradually, however, his thoughts and researches came to be steadfastly directed to the application of electricity to the communication of signals. In determining the rate at which the electric current travels through a wire he had laid down, he made an important stride towards the end in view. He proved by a series of most ingenious experiments, that one spark of electricity leaps on before another, and that its progress is a question of time. He found that electricity travels through a copper wire as fast as, if not faster, than light, that is, at the rate of 200,000 miles in a second; but through an iron wire, electricity moves at the rate of only 15,400 miles in a second. In 1836 Mr. Wheatstone had begun experiments in the vaults of King's College, with four miles of wire, properly insulated, and was working out the details of a telegraph, the scientific principles of which he had already laid down. He had discovered an original method of converting a few wires into a considerable number of circuits, so that the greatest number of signals could be transmitted by a limited number of wires, by the deflection of magnetic needles. Mr. Wheatstone, however, was somewhat backward in the mechanical parts of the scheme, and the meeting between him and Cooke was therefore of the greatest benefit to both, and an admirable illustration of the old proverb, that two heads are better than one. Had they never been brought together, – had they kept on working out their own ideas apart – each would, no doubt, have been able to produce an electric telegraph; but a great deal of time would have been lost, and their respective efforts less complete and valuable than the one they effected in conjunction. Cooke wanted sound, scientific knowledge; Wheatstone wanted mechanical ingenuity; and their union supplied mutual deficiencies. A partnership was immediately formed between them. Before their combined genius all difficulties vanished; and in the June of the same year they were able to take out a patent for a telegraph with five wires and five needles. Their respective shares in its invention are clearly marked out by Sir J. Brunel and Professor Daniell, who, as arbiters between the two upon that delicate question, gave the following award in 1841: —
"Whilst Mr. Cooke is entitled to stand alone as the gentleman to whom this country is indebted for having practically introduced and carried out the electric telegraph as a useful undertaking, promising to be a work of national importance; and Professor Wheatstone is acknowledged as the scientific man whose profound and successful researches had already prepared the public to receive it as a project capable of practical application, – it is to the united labours of two gentlemen so well qualified for mutual assistance, that we must attribute the rapid progress which this important invention has made during the five years since they have been associated."
Shortly after the taking out of a patent, wires were laid down between Euston Square Terminus and Camden Town Station, on the North-Western Railway; and the new telegraph was subjected to trial. Late in the evening of the 25th July 1837, in a dingy little room in one of the Euston Square offices, Professor Wheatstone sat alone, with a hand on each handle of the signal instrument, and an anxious eye upon the dial, with its needles as yet in motionless repose. In another little room at the Camden Town Station, Mr. Cooke was seated in a similar position before the instrument at the other end of the wires, along with Mr., now Sir Charles Fox, Robert Stephenson, and some other gentlemen. It was a trying, agitating moment for the two inventors, – how Wheatstone's pulse must have throbbed, and his heart beat, as he jerked the handle, broke the electric current, and sent the needles quivering on the dial; in what suspense he must have spent the next few minutes, holding his breath as though to hear his fellow's voice, and almost afraid to look at the dial lest no answer should be made; with what a thrill of joy must each have seen the needles wag knowingly and spell out their precious message, – the "All's well; thank God," that flashed from heart to heart, along the line of senseless wire. "Never," said Wheatstone, "did I feel such a tumultuous sensation before, as when all alone in the still room I heard the needles click; and as I spelled the words, I felt all the magnitude of the invention now proved to be practicable beyond cavil or dispute."
A few days before this trial of the telegraph in London, Steinheil, of Munich, is said to have had one of his own invention at work there; and it is a difficult question to decide whether he or Cooke and Wheatstone were the first inventors. It is, however, a question of no consequence, as each worked independently. Since the first English electric telegraph was patented, there have been a thousand and one other contrivances of a similar kind taken out; but it may be doubted whether, for practical purposes, the original apparatus, with the improvements which its own inventors have made on it, is not still the best of them all.
From being used merely to carry railway messages, the telegraph was brought into the service of the general public; the advantages of such almost instantaneous communication were readily appreciated; and eight years after Messrs. Cooke and Wheatstone took out their patent, lines of telegraph to the extent of 500 miles were in operation in England upon the original plan. In 1855 telegraphic correspondence had become so general, that the Electric Telegraph Company was started to supply the demand. In that establishment the Needle Telegraph of Wheatstone and Cooke is the one generally used, with the Chemical Recording Telegraph of Bain for special occasions. By means of the latter, blue lines of various lengths, according to an alphabet, are drawn upon a ribbon of paper, and as many as 20,000 words can be sent in an hour, though the ordinary rate is 100 per minute. In the purchase of patent rights alone, the Company have spent £170,000, and they are every year adding to the length of their wires. In June 1850 they had 6730 miles of wires, and despatched 29,245 messages a year. In December 1853 they had 24,340 miles of wires, and despatched 212,440 messages a-year. Their lines now extend over a much larger mileage, and convey a greatly increased number of messages. The Magnetic Telegraph Company have also a large extent of wires, and do a considerable business.
III. – THE SUBMARINE TELEGRAPH
The land telegraph having had such success, the next step was to carry the wires across the deep, and link continent to continent, – an all-important step for an island kingdom such as ours, with its legion of distant colonies. The success of a submerged cable between Gosport and Portsmouth, and of one across the docks at Hull, proved the feasibility of a water telegraph, at least on a small scale, and it was not long before more ambitious attempts were made. On the 28th of August 1850, a cable, 30 miles long, in a gutta percha sheathing, was stretched at the bottom of the straits between Dover and Cape Grisnez, near Calais. Messages of congratulation sped along this wire between England and France; and although a ridge of rocks filed the cable asunder on the French coast, the suspension of communication was only temporary. The link has once more been established, and is in daily use. The first news sent by the wire to England was of the celebrated coup d'etat of the 2d December, which cleared the way for Louis Napoleon's ascent of the throne. Numerous other cables have since been sunk beneath the waters; complete telegraphic communication has just been established between England and India, and will, no doubt, before long be extended to Australia.
The greatest enterprise of this kind, however, still remains unaccomplished – that is, the laying of the Atlantic cable. A company was started in 1856 to carry out this great enterprise, the governments of Great Britain and the United States engaging to assist them, not only with an annual subsidy of £10,000 a-year for twenty-five years, but to furnish the men and ships required for laying the cable from one side of the Atlantic to the other. The chief difficulty which engaged the attention of Mr. Wildman Whitehouse and the other agents of the notable enterprise was the enormous size of the cable which, it was thought, would be necessary. The general belief at that time was, that the greater the distance to be traversed, the larger must be the wire along which the electric current was to pass, and that the rate of speed would be in proportion to the size of the conductor. Mr. Whitehouse, however, thought it would be as well to begin by making sure that this was really the case, and that a monster cable was essential; and after some three thousand separate observations and experiments, was delighted to find that the difficulty which stared them in the face was imaginary. Instead of a large cable transmitting the current faster than a small one, he ascertained beyond a doubt, that the bigger the wire, the slower was the passage of the electricity. It would be needful, therefore, to make the cable only strong enough to stand the strain of its own weight, and heavy enough to sink to the bottom. A single wire would have been quite sufficient, but a strand of seven wires of the finest copper was used for the cable, so that the fracture of one of them might not interfere with the communication, – as long as one wire was left intact the current would proceed. A triple coating of gutta percha, to keep the sea from sucking out the electricity, and a thick coating of iron wire, to sink the cable to the bottom and give it strength, were added to the copper rope, and then the cable was complete. No less than 325,000 miles of iron and copper wire were woven into this great cable, – as much as might be wound thirteen times round the globe; and its weight was about a ton per mile. The length of the cable was 18,947 miles – some 600 miles being allowed to come and go upon, in case of accidents.