CHAPTER XXIV.THE INTENTIONS AND DISCOVERIES OF LORD DUNDONALD'S FATHER.—HIS OWN MECHANICAL CONTRIVANCES.—HIS LAMPS.—HIS ROTARY STEAM-ENGINE, HIS SCREW-PROPELLER, HIS CONDENSING-BOILER, AND HIS LINES OF SHIP-BUILDING.—THEIR TARDY DEVELOPMENT.—HIS CORRESPONDENCE UPON STEAM-SHIPPING WITH SIR JAMES GRAHAM, THE EARL OF MINTO, THE EARL OF HADDINGTON, AND THE EARL OF AUCKLAND.—THE PROGRESS OF HIS INVENTIONS.—THE "JANUS."—THE BENEFICIAL RESULTS OF HIS EXPERIMENTS.[1833-1847.]Lord Dundonald's father, the ninth earl, had devoted the chief energies of his long life to scientific pursuits, which won for him, not profit, but well-earned fame, and which proved of immense benefit to his own and succeeding generations. By him was discovered the art of extracting tar from coal, and out of that discovery was developed, partly by him and partly by others, the manufacture of gas, first used for lighting his tar-works. The important chemical process of making alkali and crystals of soda was also introduced by him, whereby a great impetus was given to the manufacture of glass and to many other important branches of industry. He discovered the present method of preparing alum, or sulphate of vitriol, and suggested its substitution for gum senegal, which has proved hardly less advantageous to the mechanical arts. In 1795, he published a treatise, the result of numerous and costly experiments, on the connection between agriculture and chemistry, which was almost the parent of all the later researches that have issued in beneficial plans for improving the soil and invigorating the growth of crops, and in various and important developments of scientific farming.The tenth Earl of Dundonald inherited his father's mechanical and scientific genius. The lamp invented by him in 1814, which introduced the principle upon which all later lamps for burning oil, naphtha, and other combustibles have been constructed, has been already referred to. Many other inventions and discoveries occupied his leisure during the years in which he was allowed to follow his profession both in British and in foreign service;[15]and the fuller leisure forced upon him during the years following his return from Greece was chiefly devoted to further exercise of his inventive faculties.To the wonderful invention known as his "secret war-plan" allusion will presently be made. His other most important mechanical pursuits had for their principal object the improvement of steam-engines and other appliances for steam-shipping. Almost his first reminiscence was of a visit in which, when he was seven or eight years old, he accompanied his father to Birmingham, there to meet with James Watt, and hear something of his memorable discovery. Apprehending in his youth the value of that discovery, he never wearied in his efforts to extend its usefulness. TheRising Star, built in 1818 under his directions, and those of his brother, Major Cochrane, for service in Chili, was the first steam-vessel that crossed the Atlantic, and it was an additional disappointment to him, amid all the misfortunes incident to his efforts to give adequate assistance to the Greeks in their war of independence, that the ill-fated steamers which were to be his chief instruments therein, failed through the indolence and incompetence of those to whom their construction was assigned.It is not necessary here to detail the studies and experiments by which he afterwards sought to introduce a better steam-engine, for locomotive purposes, than was then, or is even now, in general use. His plan—not a new one, though it had never before been made available in practice—was to substitute for the ordinary reciprocating engine a machine which should at once produce a circular motion. "Of the many rotary engines heretofore offered to the notice of the world," he wrote, in 1833, "none have stood the test of practical use and experience. The cause of this uniform failure has been the great difficulty of obtaining, within the machine, a base of resistance on which the steam might act in propelling the moveable piston." He did not quite overcome this difficulty, but he succeeded in producing what the foremost critic in this department of manufacture describes—after a lapse of thirty years unrivalled for their development of ingenuity—as "the most perfect engine of the class that has yet been projected.""In this engine," says the same authority, "an eccentric is made to revolve on an axis in the manner of a piston, and two doors, forming part of the side of the cylinder, press upon the eccentric. The points of these doors are armed with swivelling brasses, which apply themselves to the eccentric and make the point of contact tight in all positions."[16]"This revolving engine," said Lord Dundonald, "does not require any valve or slide; consequently, there is no waste of steam thereby; neither is there any loss, as in the space left at the top and bottom of the cylinders of reciprocating engines. There is much less friction than arises from the sum of all the bearings required to convert the rectilineal force of the common engine to circular motion. There are no beams, cranks, side-rods, connecting-rods, parallel motions, levers, slide-valves, or eccentrics, with their nicely-adjusted joints and bearings; and thus the revolving engine is not liable, even in one-tenth degree, to the accidents and hindrances of other engines. As its moving parts pursue their course in perfect circles, without stop or hindrance, it is capable of progressive acceleration, until the work performed equals the pressure of steam on the vacuum—an advantage which the reciprocating engine does not possess. The diminished bulk and weight, and the absence of tremor, add to the capacity, buoyancy, velocity, and durability of vessels in which it is placed." The rotary engine did not satisfy all Lord Dundonald's expectations, but it took precedence of all others of the same sort, and was of great service at any rate in directing attention to what he rightly considered to be the great want in war-shipping, namely, vessels of the least possible bulk and of the greatest possible strength, speed, and fighting power.Years were spent by him in attempting to bring it into notice. At his own cost he fitted out a little steamboat, which navigated the Thames; but to perfect the invention were required more funds than he had at his command, and he sought in vain for adequate assistance from others.In January, 1834, he wrote to Sir James Graham, then First Lord of the Admiralty, thanking him for his share in the restitution of his naval rank that had occurred nearly two years before, and urging the co-operation of the Government in perfecting an invention that promised to be of so much importance to the naval power of England. "You are not obliged to me for anything," answered Sir James on the 15th; "I only am fortunate in being the member of a Government which has regained for our country the benefit of your distinguished valour and services, which, if again required in war, will, I am persuaded, be so exerted as to win the gratitude of the nation, and to demonstrate the justice of the decision to which you allude. It is impossible to over-estimate the paramount importance of steam in future naval operations; and it is fortunate that you have directed so much of your attention to the subject. The Board has complied with your request, and two engineers, in whom we place reliance, will be ordered to attend you." It does not appear, how-ever, that the engineers did attend. At any rate, nothing was done by the Admiralty in aid of the invention either then or for many years after.Yet its ingenuity was acknowledged by all who investigated it, and by naval authorities among the number. The Earl of Minto, when First Lord of the Admiralty, sought to introduce it into the national ship-building; but official hindrances, too great even for him to overcome, stood in his way. All he could do was to have it referred to competent judges and to receive their report in its favour. "I am commanded to acquaint your lordship," wrote Sir John Barrow, the Secretary to the Admiralty, to the Earl of Dundonald, on the 20th of December, 1839, "that the opinions received of your revolving engine are favourable to the principle, and that it has not been stated that there are any insurmountable obstacles to its practical execution." The insurmountable obstacles were in the stolid resistance of subordinates to any novelty designed to lessen labour and promote economy.Lord Minto, when out of office, was able to speak of the engine in more approving terms than he could adopt in his official capacity. "I need hardly say," he wrote on the 6th of September, 1842, "that the report of continued success in your rotatory engine gives me great pleasure, not only upon your own account, but as promising a valuable addition to our naval power in its application to ships of war. As a high-pressure engine, the complete success of your plan has, I believe, been recognised by all who have attended to it, and it is in this form that I had contemplated its application in the first instance as an auxiliary and occasional power in some ships of war."At length, though not with all the energy that he desired, Lord Dundonald's engine was put to the test by the Admiralty during the Earl of Haddington's tenure of office in that department. In May, 1842, he was invited by the new First Lord, who, in common with all the world, was aware of the zeal and intelligence with which he had devoted himself to the consideration of every branch of naval science, to communicate his opinions thereupon. The first result of this invitation was a letter showing remarkable discernment of evils then existing, and curiously anticipating some later efforts to correct them."The slow progress," wrote Lord Dundonald, on the 7th of June, "which the naval service has made towards its present ameliorated state—yet far from perfection—has not permitted any one Board of Admiralty in my time to stand pre-eminently distinguished for decisive improvements. These have rather been effected by the gradual changes which time occasions, or by following the example of America, or even of France, than by encouraging efforts of native genius. This has arisen from causes easily remedied; one of which is, that the rejection or adoption of proffered improvements has depended on the decision of several authorities, who consequently feel little individual responsibility, and imagine themselves liable to censure only for a change of system. Thus, my lord, a still heavier responsibility has, in fact, been incurred by continuing, long after the most superficial observation demanded a change, to construct small ships of the line, and little frigates, which the great practical skill and bravery of our countrymen were taxed to defend against the powerful eighty-gun ships of France and the large frigates of America. This timidity as to change caused many years to elapse, after the commercial use of steam-vessels, before the naval department possessed even a tug-boat. Hence the mischievous economy manifested by the purchase of worthless merchant steamers; hence the subsequent parsimonious project of building small steam-vessels fitted with engines immersed beyond their bearing, and deficient in every requisite for purposes of war. I am not one of those, my lord, who deem it advantageous to act on the belief that one Englishman can beat two Frenchmen. I am inclined to doubt whether a practical demonstration of that saying might not be attended with disastrous consequences. Long habitude reared experienced British officers, who are now replaced by others who possess less nautical skill, and are nearer on a par with those of France, in regard to whose education every pains has been taken by its Government. I do not presume to advise that your lordship should adopt changes precipitately, nor without consulting those who may be most competent to judge; no, nor even then that the best measures should be prematurely disclosed, so as to give intimation to other nations of the vast increase of power which may suddenly be rendered available. But I venture to suggest that you may quietly prepare the means of effecting purposes which neither the ordinary ships of war nor the present steam-ships in the navy can accomplish. Permanent blockades, my lord, are now quite out of the question; and so, in my opinion, are all our ordinary naval tactics. A couple of heavy line-of-battle ships, suddenly fitted, on the outbreak of war, with adequate steam-power, would decide the successful result of a general action; and I am assured that I could show your lordship how to fit a steam-ship which, in scouring the Channel or ranging the coast, could take or destroy every steam-ship belonging to France that came within view."That offer was accepted by the Earl of Haddington, who, being at Portsmouth in August, made personal inspection of some experiments in which Lord Dundonald was there engaging; and the result of that inspection was that he promptly arranged for the introduction, at the public expense, of the rotary engine in theFirefly, a small steam-vessel which, like many others, the Government had bought and found useless, by reason of its clumsy machinery. In her, with no more than the usual delay occasioned by the co-operation of official routine with private enterprise, in which Lord Dundonald had the assistance of Mr. Renton and Messrs. Bramah, the experiment was tried and found to answer so well, in spite of the difficulties incident to a first attempt, that it was resolved to develop it further in a frigate to be built throughout in accordance with his plans for the improved construction of shipping.To these he had lately made some valuable additions. On the 19th of January, 1843, a patent was granted to him for various improvements in engines and other machinery, one of which was an apparatus for propelling vessels. "This improved propeller," says a competent authority, "consists of an arrangement of propelling blades immerged beneath the water, in the manner now usual in screw vessels; but, instead of the blades being set at right angles with the propeller-shaft, they form an angle therewith. One important effect of this arrangement is that it corrects the centrifugal action of the screw; for whereas, in common screws, the water which is discharged backwards assumes a conical figure, enlarging as it recedes, in a screw formed on Lord Dundonald's plan the outline of the moving water will be cylindrical, the centrifugal action being counteracted by the convergent action due to the backward inclination of the propelling blades. It is found, practically, that screws constructed upon this principle give a better result than ordinary screws."[17]Another invention patented by Lord Dundonald at the same time was a modification of the boilers used for steam-engines. "These boilers," says the same critic, "are constructed with a double tier of furnaces and with upright tubes, the water being contained within the tubes and the smoke impinging upon them on its passage to the chimney. This species of boiler is found to be very efficient. A hanging bridge is introduced to retain the heat in the upper part of the flue in which the tubes are erected. By inserting a short piece of tube in the upper extremity of each tube within the boiler the upward circulation of the water within the tubes was increased as the length of the lighter column of water was augmented, while the length of the gravitating column remained without alteration."[18]"I believe," he said in a letter to Lord Haddington dated the 22nd of May, 1843, "that all our old vessels of war, save the class of eighty-gun ships and a few first-rate and large frigates, are almost worthless; whilst our steam department is deficient in most of the properties which constitute effective vessels. No blockades worthy of the name can now be maintained by fleets of sailing ships; nor can accompanying steamships be kept for months and years even in 'approximate readiness,' awaiting the distant night when it may suit the enemy to attack our blockading force or quietly to slip out in the dark in order to assail our commerce in other quarters. I have, my lord, during the last twelve years actually disbursed, to the great inconvenience of my family, upwards of 16,000l. to promote nautical objects which appeared to me of importance. Your lordship knows their nature, and it is in no way difficult to ascertain their reality. I consider that several, if not all our line-of-battle ships, should have the benefit of mechanical power, say to the extent of a hundred horses—the machinery to be placed out of the reach of shot. The construction of new ships on the best lines that could be found would prove more judicious than repairing old ones, however apparently cheap such repairs may be; for a few powerful and quick-sailing ships are preferable to a multitude which can neither successfully chase, nor escape from, an enemy."That allusion to the "best lines" of ship-building, and some of Lord Dundonald's other views on naval architecture, will be explained by another letter written by him to Lord Haddington, three months before, on the 20th of February. "I have lately," he said, "submitted to the consideration of Sir George Cockburn an axiom for the uniform delineation of consecutive parabolic curves, forming a series of lines presenting the least resistance in the submerged portion of ships and vessels—an axiom never before so applied in naval architecture, as is manifest from the discrepant forms of our ships of war. I also offered to Sir George's attention a new propeller and method of adapting propellers to sailing ships in her Majesty's service, free from the disadvantages of paddle-wheels and from the injurious consequences of lessening the buoyancy and weakening the strength of the after part of ships by a prolongation of the 'dead wood,' and by cutting a large hole through it for the insertion of the Archimedean screw. The favourable impression made on the mind of Sir George, and my own deliberate conviction of the importance of these improvements, and of others then briefly touched on, lead me, by reason of the lamented indisposition of that talented officer, now personally, instead of through him, to offer them to your lordship's attention."The French, as your lordship is well aware, are making great exertions to advance their steam department, especially in the Mediterranean, where calms are frequent and their coal is abundant—doubtless in the hope of thereby preventing the future blockade of Toulon, and of keeping open their intercourse with Algiers; which would be equivalent to possessing the dominion of the Mediterranean Sea, where a British blockading fleet of sailing ships must, under such circumstances, themselves be protected. In saying this, my lord, I beg to be understood as by no means depreciating the capabilities of our common ships of war, whilst they possess the power of motion, but as holding them to be quite unfit for blockades, and exposed to great peril where calms are of frequent occurrence and long duration. Indeed, it may be worthy of your lordship's serious consideration whether, in another point of view, it might not be judicious to place steam-engines in some, at least, of our line-of-battle ships, in order to divert the attention of foreign nations from the exclusive employment of mechanical propelling power to purposes of naval war, whereby British officers and seamen, deprived of the means of displaying their superior skill, become reduced to a par with the trained bands of Continental states."I have prepared a model in bronze of a steam-frigate possessing peculiar properties, founded on the before-mentioned axiom, which, I do not hesitate to submit to your lordship, would save vast sums wasted in the construction of inferior ships and vessels, by enabling the Admiralty, on unerring data, to stereotype—if I may use the expression—every curve in every rate or class of ships, and so impose on constructors the undeviating task of adhering to the lines and models scientifically determined on by their lordships."[19]Great interest attended the development of Lord Dundonald's inventions. "I need hardly assure you," wrote Lord Minto, on the 4th of October, "of the very great satisfaction I derive from the continued and increasing success of your rotatory engine; and I shall now look with no little impatience for further evidence of its merits in the new steam-frigate to which it is to be applied. I am glad, also, that you have turned your attention to the construction of steamers of war. I have never been satisfied with the properties of these vessels, much as their construction has undoubtedly been improved of late years. It is certainly a difficult subject, because some of the qualities essential to a vessel under sail can only be obtained by some deviation from the form calculated to give the greatest speed under steam; and I consider fair sailing powers, so as under all circumstances to keep company with a fleet, as not less important than speed and power as a steamer. The best combination of these very different qualities, or that which will upon the whole produce the most serviceable ship, is yet to be sought. I think, also, that sufficient consideration has not yet been given to the correction of that very grievous defect, the great uneasiness and excessive rolling of all these vessels, from the low position of the weights they carry. There is another object in connection with your engine which I had constantly in view: I mean its adaptation in the high-pressure form to our ships of war in general. It was my intention, had I remained in office, to have fitted a frigate with one of your high-pressure engines—not very high, however—with a view, if the experiment answered, to the introduction of an occasional steam power in all ships of the line. I believe you and I may probably differ as to the amount of steam power it might be advisable to give such ships, and that you would wish to steam theVanguardor theQueenat the rate of ten miles an hour. My wishes are much more humble, and I should be perfectly satisfied with an amount of power sufficient to give steerage way under all circumstances, to carry the ship into or out of action, and to afford her some assistance in clearing off a lee-shore—something about equivalent to five knots—an amount of power that might probably be obtained, together with some fuel for occasional use, without encroaching too much upon the stowage of the ship. I shall be extremely glad if you can induce Lord Haddington to direct his attention to this object."Through the latter part of 1843 and the whole of 1844, Lord Dundonald was chiefly occupied with the construction of theJanus, the steam-frigate which was being built and fitted upon his plans. She was shaped in accordance with his "lines," and in her were introduced both his revolving engines and his improved boilers. "I have just returned from Chatham," he wrote to a friend on the 6th of April, 1844, "where everything regarding theJanusis going on very well indeed. And I have further good news to tell you. The Admiralty are so pleased with my parabolic lines for ship-building that they have ordered a drawing to be made immediately of a frigate of the first class, in order to have one constructed." Hopeful that at last his long-cherished ideas would bring benefit both to himself and to the nation, he had in these months much to encourage him. "All is going on as well as I could wish, or even as I could accomplish, were destiny at my command," he wrote on the 31st of May. "The Portsmouth engines now meet the approbation of all the authorities of the yard, and the Admiralty are so satisfied that they have given me the building of a steamship to put them in, in lieu of placing them in the oldFirefly." "Nothing," he said in a letter written a week or two later, "can exceed the perfection of the work which the Bramahs have put into theJanus'sengines." "The experimental engine at Portsmouth," he wrote on the 3rd of July, "continues to perform admirably, beating all others in the yard in point of vacuum, which, you know, is the test of power." "The engines will commence being put together in ten or fourteen days," we read in another letter dated the 10th of July; "after that we shall make rapid progress. TheJanusis now completing—that is, being coppered—and having the part of her deck laid down which was left off for the purpose of getting the boilers on board. My patent boilers will be tried by authority of the Admiralty about the 20th, and I hope for a favourable result." The trial, postponed till the 1st of August, was satisfactory. "We have tried the boilers of theJanus," he wrote on that day, "and the result is most triumphant, having, with slack firing, ten and a half pounds of water evaporated by each pound of coal." "I have just returned from Portsmouth," he had written five days before, "where I had the pleasure to find my engine exceeding even all that it had done before—the vacuum, with all the work on, being 28½, two inches above that of any other engine in the dockyard. Mr. Taplin, the chief engineer, is quite delighted with it." "Sir George Cockburn and Sir John Barrow, permanent Secretary of the Admiralty, saw my engine yesterday," he wrote on the 24th of October, concerning the machine being built by the Bramahs for theJanus; "and so did Lord Brougham; all of whom were well pleased with my explanation of its principles and the appearance of the workmanship. It is now being pulled to pieces, in order to its being sent to Chatham and set up on board theJanus, whose boilers, by my request, are again to be officially tested as to their evaporative power, and that, too, by the Woolwich authorities, whose boilers have been beaten one-third by the evaporation of mine. This request must show the Admiralty my confidence in the correctness of the former trial; for there is no doubt the Woolwich people would condemn it if they could." This second and crucial trial took place on the 9th of November, and the result exceeded alike Lord Dundonald's expectations and those of the official judges, to whom failure would have been most pleasant. "All matters as regards my engines," he wrote on the 20th of November, "are going on well. I hope soon to hear something satisfactory from the Admiralty on the subject of the boilers, respecting which they have until now pursued the most profound silence, notwithstanding the triumphant result, which has surpassed the product of the far-famed Cornish boilers in evaporative power."Those extracts from Lord Dundonald's letters to the friend with whom he corresponded most freely will suffice to show in what temper he watched the progress of his inventions during 1844. At the close of the year he hoped that his labours to bring them into general use were now nearly at an end; but in this he was disappointed. The Woolwich authorities, who had at the time expressed their approval of the boilers, sent in an adverse report to the Admiralty, and Lord Dundonald had to wait several months before he could disprove the statements made against them; and opposition of the same sort—the common experience of nearly every inventor—encountered him at every turn, and had again and again to be overcome. His Portsmouth engine continued to work well; but in September, 1845, he learnt that a malicious trick had been resorted to, to prevent its working better. "On a recent examination of the pumps in the well," wrote Mr. Taplin, the engineer, "to our utter astonishment we found, in the middle suction pipe, an elm plug, driven in so tight that we were obliged to bore and cut it out. The plug stopped that suction pipe effectually, and from its appearance must have been there from the time the pumps were first put in motion. As proof of this, we never had such a supply of water as at present." And that is only an illustration of the obstacles, accidental or designed, that occurred to him.By them, theJanuswas delayed for a whole year. She was to have been completed in 1844; but this was not done till the end of 1845. "I have just returned," Lord Dundonald was able to write on the 24th of December, "from a nine days' trip in theJanus, the result of which has been successful, both in regard to the properties of the engines and those of the 'lines' on which she has been constructed. Nothing can exceed the beauty of her passage through the water, without even a ripple, far less the wave which ordinary steamboats occasion." That success, however, was to be followed by a long series of disasters. The weight of theJanushad been miscalculated, and though she could proceed admirably in smooth water, she was found to lie so low that there was constant danger of her being wrecked in rough seas and bad weather. Other faults, incident to the bringing together for the first time of so much new workmanship, were also discovered. She had to be returned to dock, and fresh hindrances of every sort occurred during the two following years; each hindrance being attended by tedious correspondence or controversies with petty functionaries jealous of a stranger's interference, and only eager to bring discredit upon his work. Much discredit did result. Loud complaints were made concerning the waste of public money resulting from Lord Dundonald's experiments, and on him, of course, nearly all the blame was thrown. All this, added to his previous difficulties in securing for his boiler and engine any notice at all, was very grievous to him. Every complaint and every entreaty from him was met by a new excuse and a new reason for delay. "Ten days are always added," he said, in one letter, "and ten days yet are said to be required."The days became weeks and the weeks months, and still theJanuswas incomplete. She was unfinished when Lord Dundonald left England for more than two years in order to fulfil the duties assigned to him as commander-in-chief of the North American and West Indian squadron, and his absence caused a final abandonment of the works.The tedious process of her construction, however, to which only sufficient reference has here been made to serve as illustration of one phase of Lord Dundonald's life, was attended by many good results. To himself she brought only trouble and expense; but the obstacles thrown in her way and in his did not deter private adventurers from acting upon some of the principles developed in abortive attempts at her completion by public functionaries. Lord Dundonald's inventions—his revolving engine, his screw-propeller, his boiler, and his "lines of ship-building,"—have all proved useful in themselves, and have been of yet greater use in their influence upon the improved mechanism of our own generation.To him must be attributed no slight share in the revolution that has been effected in the materials for naval warfare. Of the superiority of steamers to war-ships, he was one of the first advocates. His own rotatory engine was never extensively adopted, and was superseded by other engines which, lacking the great merit of direct action upon the paddles, that it was his object to attain, had other and greater merits of their own; but in their adoption his great object was realized, seeing that that object was not his own aggrandisement, but the development of the naval strength of England.
THE INTENTIONS AND DISCOVERIES OF LORD DUNDONALD'S FATHER.—HIS OWN MECHANICAL CONTRIVANCES.—HIS LAMPS.—HIS ROTARY STEAM-ENGINE, HIS SCREW-PROPELLER, HIS CONDENSING-BOILER, AND HIS LINES OF SHIP-BUILDING.—THEIR TARDY DEVELOPMENT.—HIS CORRESPONDENCE UPON STEAM-SHIPPING WITH SIR JAMES GRAHAM, THE EARL OF MINTO, THE EARL OF HADDINGTON, AND THE EARL OF AUCKLAND.—THE PROGRESS OF HIS INVENTIONS.—THE "JANUS."—THE BENEFICIAL RESULTS OF HIS EXPERIMENTS.
[1833-1847.]
Lord Dundonald's father, the ninth earl, had devoted the chief energies of his long life to scientific pursuits, which won for him, not profit, but well-earned fame, and which proved of immense benefit to his own and succeeding generations. By him was discovered the art of extracting tar from coal, and out of that discovery was developed, partly by him and partly by others, the manufacture of gas, first used for lighting his tar-works. The important chemical process of making alkali and crystals of soda was also introduced by him, whereby a great impetus was given to the manufacture of glass and to many other important branches of industry. He discovered the present method of preparing alum, or sulphate of vitriol, and suggested its substitution for gum senegal, which has proved hardly less advantageous to the mechanical arts. In 1795, he published a treatise, the result of numerous and costly experiments, on the connection between agriculture and chemistry, which was almost the parent of all the later researches that have issued in beneficial plans for improving the soil and invigorating the growth of crops, and in various and important developments of scientific farming.
The tenth Earl of Dundonald inherited his father's mechanical and scientific genius. The lamp invented by him in 1814, which introduced the principle upon which all later lamps for burning oil, naphtha, and other combustibles have been constructed, has been already referred to. Many other inventions and discoveries occupied his leisure during the years in which he was allowed to follow his profession both in British and in foreign service;[15]and the fuller leisure forced upon him during the years following his return from Greece was chiefly devoted to further exercise of his inventive faculties.
To the wonderful invention known as his "secret war-plan" allusion will presently be made. His other most important mechanical pursuits had for their principal object the improvement of steam-engines and other appliances for steam-shipping. Almost his first reminiscence was of a visit in which, when he was seven or eight years old, he accompanied his father to Birmingham, there to meet with James Watt, and hear something of his memorable discovery. Apprehending in his youth the value of that discovery, he never wearied in his efforts to extend its usefulness. TheRising Star, built in 1818 under his directions, and those of his brother, Major Cochrane, for service in Chili, was the first steam-vessel that crossed the Atlantic, and it was an additional disappointment to him, amid all the misfortunes incident to his efforts to give adequate assistance to the Greeks in their war of independence, that the ill-fated steamers which were to be his chief instruments therein, failed through the indolence and incompetence of those to whom their construction was assigned.
It is not necessary here to detail the studies and experiments by which he afterwards sought to introduce a better steam-engine, for locomotive purposes, than was then, or is even now, in general use. His plan—not a new one, though it had never before been made available in practice—was to substitute for the ordinary reciprocating engine a machine which should at once produce a circular motion. "Of the many rotary engines heretofore offered to the notice of the world," he wrote, in 1833, "none have stood the test of practical use and experience. The cause of this uniform failure has been the great difficulty of obtaining, within the machine, a base of resistance on which the steam might act in propelling the moveable piston." He did not quite overcome this difficulty, but he succeeded in producing what the foremost critic in this department of manufacture describes—after a lapse of thirty years unrivalled for their development of ingenuity—as "the most perfect engine of the class that has yet been projected."
"In this engine," says the same authority, "an eccentric is made to revolve on an axis in the manner of a piston, and two doors, forming part of the side of the cylinder, press upon the eccentric. The points of these doors are armed with swivelling brasses, which apply themselves to the eccentric and make the point of contact tight in all positions."[16]
"This revolving engine," said Lord Dundonald, "does not require any valve or slide; consequently, there is no waste of steam thereby; neither is there any loss, as in the space left at the top and bottom of the cylinders of reciprocating engines. There is much less friction than arises from the sum of all the bearings required to convert the rectilineal force of the common engine to circular motion. There are no beams, cranks, side-rods, connecting-rods, parallel motions, levers, slide-valves, or eccentrics, with their nicely-adjusted joints and bearings; and thus the revolving engine is not liable, even in one-tenth degree, to the accidents and hindrances of other engines. As its moving parts pursue their course in perfect circles, without stop or hindrance, it is capable of progressive acceleration, until the work performed equals the pressure of steam on the vacuum—an advantage which the reciprocating engine does not possess. The diminished bulk and weight, and the absence of tremor, add to the capacity, buoyancy, velocity, and durability of vessels in which it is placed." The rotary engine did not satisfy all Lord Dundonald's expectations, but it took precedence of all others of the same sort, and was of great service at any rate in directing attention to what he rightly considered to be the great want in war-shipping, namely, vessels of the least possible bulk and of the greatest possible strength, speed, and fighting power.
Years were spent by him in attempting to bring it into notice. At his own cost he fitted out a little steamboat, which navigated the Thames; but to perfect the invention were required more funds than he had at his command, and he sought in vain for adequate assistance from others.
In January, 1834, he wrote to Sir James Graham, then First Lord of the Admiralty, thanking him for his share in the restitution of his naval rank that had occurred nearly two years before, and urging the co-operation of the Government in perfecting an invention that promised to be of so much importance to the naval power of England. "You are not obliged to me for anything," answered Sir James on the 15th; "I only am fortunate in being the member of a Government which has regained for our country the benefit of your distinguished valour and services, which, if again required in war, will, I am persuaded, be so exerted as to win the gratitude of the nation, and to demonstrate the justice of the decision to which you allude. It is impossible to over-estimate the paramount importance of steam in future naval operations; and it is fortunate that you have directed so much of your attention to the subject. The Board has complied with your request, and two engineers, in whom we place reliance, will be ordered to attend you." It does not appear, how-ever, that the engineers did attend. At any rate, nothing was done by the Admiralty in aid of the invention either then or for many years after.
Yet its ingenuity was acknowledged by all who investigated it, and by naval authorities among the number. The Earl of Minto, when First Lord of the Admiralty, sought to introduce it into the national ship-building; but official hindrances, too great even for him to overcome, stood in his way. All he could do was to have it referred to competent judges and to receive their report in its favour. "I am commanded to acquaint your lordship," wrote Sir John Barrow, the Secretary to the Admiralty, to the Earl of Dundonald, on the 20th of December, 1839, "that the opinions received of your revolving engine are favourable to the principle, and that it has not been stated that there are any insurmountable obstacles to its practical execution." The insurmountable obstacles were in the stolid resistance of subordinates to any novelty designed to lessen labour and promote economy.
Lord Minto, when out of office, was able to speak of the engine in more approving terms than he could adopt in his official capacity. "I need hardly say," he wrote on the 6th of September, 1842, "that the report of continued success in your rotatory engine gives me great pleasure, not only upon your own account, but as promising a valuable addition to our naval power in its application to ships of war. As a high-pressure engine, the complete success of your plan has, I believe, been recognised by all who have attended to it, and it is in this form that I had contemplated its application in the first instance as an auxiliary and occasional power in some ships of war."
At length, though not with all the energy that he desired, Lord Dundonald's engine was put to the test by the Admiralty during the Earl of Haddington's tenure of office in that department. In May, 1842, he was invited by the new First Lord, who, in common with all the world, was aware of the zeal and intelligence with which he had devoted himself to the consideration of every branch of naval science, to communicate his opinions thereupon. The first result of this invitation was a letter showing remarkable discernment of evils then existing, and curiously anticipating some later efforts to correct them.
"The slow progress," wrote Lord Dundonald, on the 7th of June, "which the naval service has made towards its present ameliorated state—yet far from perfection—has not permitted any one Board of Admiralty in my time to stand pre-eminently distinguished for decisive improvements. These have rather been effected by the gradual changes which time occasions, or by following the example of America, or even of France, than by encouraging efforts of native genius. This has arisen from causes easily remedied; one of which is, that the rejection or adoption of proffered improvements has depended on the decision of several authorities, who consequently feel little individual responsibility, and imagine themselves liable to censure only for a change of system. Thus, my lord, a still heavier responsibility has, in fact, been incurred by continuing, long after the most superficial observation demanded a change, to construct small ships of the line, and little frigates, which the great practical skill and bravery of our countrymen were taxed to defend against the powerful eighty-gun ships of France and the large frigates of America. This timidity as to change caused many years to elapse, after the commercial use of steam-vessels, before the naval department possessed even a tug-boat. Hence the mischievous economy manifested by the purchase of worthless merchant steamers; hence the subsequent parsimonious project of building small steam-vessels fitted with engines immersed beyond their bearing, and deficient in every requisite for purposes of war. I am not one of those, my lord, who deem it advantageous to act on the belief that one Englishman can beat two Frenchmen. I am inclined to doubt whether a practical demonstration of that saying might not be attended with disastrous consequences. Long habitude reared experienced British officers, who are now replaced by others who possess less nautical skill, and are nearer on a par with those of France, in regard to whose education every pains has been taken by its Government. I do not presume to advise that your lordship should adopt changes precipitately, nor without consulting those who may be most competent to judge; no, nor even then that the best measures should be prematurely disclosed, so as to give intimation to other nations of the vast increase of power which may suddenly be rendered available. But I venture to suggest that you may quietly prepare the means of effecting purposes which neither the ordinary ships of war nor the present steam-ships in the navy can accomplish. Permanent blockades, my lord, are now quite out of the question; and so, in my opinion, are all our ordinary naval tactics. A couple of heavy line-of-battle ships, suddenly fitted, on the outbreak of war, with adequate steam-power, would decide the successful result of a general action; and I am assured that I could show your lordship how to fit a steam-ship which, in scouring the Channel or ranging the coast, could take or destroy every steam-ship belonging to France that came within view."
That offer was accepted by the Earl of Haddington, who, being at Portsmouth in August, made personal inspection of some experiments in which Lord Dundonald was there engaging; and the result of that inspection was that he promptly arranged for the introduction, at the public expense, of the rotary engine in theFirefly, a small steam-vessel which, like many others, the Government had bought and found useless, by reason of its clumsy machinery. In her, with no more than the usual delay occasioned by the co-operation of official routine with private enterprise, in which Lord Dundonald had the assistance of Mr. Renton and Messrs. Bramah, the experiment was tried and found to answer so well, in spite of the difficulties incident to a first attempt, that it was resolved to develop it further in a frigate to be built throughout in accordance with his plans for the improved construction of shipping.
To these he had lately made some valuable additions. On the 19th of January, 1843, a patent was granted to him for various improvements in engines and other machinery, one of which was an apparatus for propelling vessels. "This improved propeller," says a competent authority, "consists of an arrangement of propelling blades immerged beneath the water, in the manner now usual in screw vessels; but, instead of the blades being set at right angles with the propeller-shaft, they form an angle therewith. One important effect of this arrangement is that it corrects the centrifugal action of the screw; for whereas, in common screws, the water which is discharged backwards assumes a conical figure, enlarging as it recedes, in a screw formed on Lord Dundonald's plan the outline of the moving water will be cylindrical, the centrifugal action being counteracted by the convergent action due to the backward inclination of the propelling blades. It is found, practically, that screws constructed upon this principle give a better result than ordinary screws."[17]
Another invention patented by Lord Dundonald at the same time was a modification of the boilers used for steam-engines. "These boilers," says the same critic, "are constructed with a double tier of furnaces and with upright tubes, the water being contained within the tubes and the smoke impinging upon them on its passage to the chimney. This species of boiler is found to be very efficient. A hanging bridge is introduced to retain the heat in the upper part of the flue in which the tubes are erected. By inserting a short piece of tube in the upper extremity of each tube within the boiler the upward circulation of the water within the tubes was increased as the length of the lighter column of water was augmented, while the length of the gravitating column remained without alteration."[18]
"I believe," he said in a letter to Lord Haddington dated the 22nd of May, 1843, "that all our old vessels of war, save the class of eighty-gun ships and a few first-rate and large frigates, are almost worthless; whilst our steam department is deficient in most of the properties which constitute effective vessels. No blockades worthy of the name can now be maintained by fleets of sailing ships; nor can accompanying steamships be kept for months and years even in 'approximate readiness,' awaiting the distant night when it may suit the enemy to attack our blockading force or quietly to slip out in the dark in order to assail our commerce in other quarters. I have, my lord, during the last twelve years actually disbursed, to the great inconvenience of my family, upwards of 16,000l. to promote nautical objects which appeared to me of importance. Your lordship knows their nature, and it is in no way difficult to ascertain their reality. I consider that several, if not all our line-of-battle ships, should have the benefit of mechanical power, say to the extent of a hundred horses—the machinery to be placed out of the reach of shot. The construction of new ships on the best lines that could be found would prove more judicious than repairing old ones, however apparently cheap such repairs may be; for a few powerful and quick-sailing ships are preferable to a multitude which can neither successfully chase, nor escape from, an enemy."
That allusion to the "best lines" of ship-building, and some of Lord Dundonald's other views on naval architecture, will be explained by another letter written by him to Lord Haddington, three months before, on the 20th of February. "I have lately," he said, "submitted to the consideration of Sir George Cockburn an axiom for the uniform delineation of consecutive parabolic curves, forming a series of lines presenting the least resistance in the submerged portion of ships and vessels—an axiom never before so applied in naval architecture, as is manifest from the discrepant forms of our ships of war. I also offered to Sir George's attention a new propeller and method of adapting propellers to sailing ships in her Majesty's service, free from the disadvantages of paddle-wheels and from the injurious consequences of lessening the buoyancy and weakening the strength of the after part of ships by a prolongation of the 'dead wood,' and by cutting a large hole through it for the insertion of the Archimedean screw. The favourable impression made on the mind of Sir George, and my own deliberate conviction of the importance of these improvements, and of others then briefly touched on, lead me, by reason of the lamented indisposition of that talented officer, now personally, instead of through him, to offer them to your lordship's attention.
"The French, as your lordship is well aware, are making great exertions to advance their steam department, especially in the Mediterranean, where calms are frequent and their coal is abundant—doubtless in the hope of thereby preventing the future blockade of Toulon, and of keeping open their intercourse with Algiers; which would be equivalent to possessing the dominion of the Mediterranean Sea, where a British blockading fleet of sailing ships must, under such circumstances, themselves be protected. In saying this, my lord, I beg to be understood as by no means depreciating the capabilities of our common ships of war, whilst they possess the power of motion, but as holding them to be quite unfit for blockades, and exposed to great peril where calms are of frequent occurrence and long duration. Indeed, it may be worthy of your lordship's serious consideration whether, in another point of view, it might not be judicious to place steam-engines in some, at least, of our line-of-battle ships, in order to divert the attention of foreign nations from the exclusive employment of mechanical propelling power to purposes of naval war, whereby British officers and seamen, deprived of the means of displaying their superior skill, become reduced to a par with the trained bands of Continental states.
"I have prepared a model in bronze of a steam-frigate possessing peculiar properties, founded on the before-mentioned axiom, which, I do not hesitate to submit to your lordship, would save vast sums wasted in the construction of inferior ships and vessels, by enabling the Admiralty, on unerring data, to stereotype—if I may use the expression—every curve in every rate or class of ships, and so impose on constructors the undeviating task of adhering to the lines and models scientifically determined on by their lordships."[19]
Great interest attended the development of Lord Dundonald's inventions. "I need hardly assure you," wrote Lord Minto, on the 4th of October, "of the very great satisfaction I derive from the continued and increasing success of your rotatory engine; and I shall now look with no little impatience for further evidence of its merits in the new steam-frigate to which it is to be applied. I am glad, also, that you have turned your attention to the construction of steamers of war. I have never been satisfied with the properties of these vessels, much as their construction has undoubtedly been improved of late years. It is certainly a difficult subject, because some of the qualities essential to a vessel under sail can only be obtained by some deviation from the form calculated to give the greatest speed under steam; and I consider fair sailing powers, so as under all circumstances to keep company with a fleet, as not less important than speed and power as a steamer. The best combination of these very different qualities, or that which will upon the whole produce the most serviceable ship, is yet to be sought. I think, also, that sufficient consideration has not yet been given to the correction of that very grievous defect, the great uneasiness and excessive rolling of all these vessels, from the low position of the weights they carry. There is another object in connection with your engine which I had constantly in view: I mean its adaptation in the high-pressure form to our ships of war in general. It was my intention, had I remained in office, to have fitted a frigate with one of your high-pressure engines—not very high, however—with a view, if the experiment answered, to the introduction of an occasional steam power in all ships of the line. I believe you and I may probably differ as to the amount of steam power it might be advisable to give such ships, and that you would wish to steam theVanguardor theQueenat the rate of ten miles an hour. My wishes are much more humble, and I should be perfectly satisfied with an amount of power sufficient to give steerage way under all circumstances, to carry the ship into or out of action, and to afford her some assistance in clearing off a lee-shore—something about equivalent to five knots—an amount of power that might probably be obtained, together with some fuel for occasional use, without encroaching too much upon the stowage of the ship. I shall be extremely glad if you can induce Lord Haddington to direct his attention to this object."
Through the latter part of 1843 and the whole of 1844, Lord Dundonald was chiefly occupied with the construction of theJanus, the steam-frigate which was being built and fitted upon his plans. She was shaped in accordance with his "lines," and in her were introduced both his revolving engines and his improved boilers. "I have just returned from Chatham," he wrote to a friend on the 6th of April, 1844, "where everything regarding theJanusis going on very well indeed. And I have further good news to tell you. The Admiralty are so pleased with my parabolic lines for ship-building that they have ordered a drawing to be made immediately of a frigate of the first class, in order to have one constructed." Hopeful that at last his long-cherished ideas would bring benefit both to himself and to the nation, he had in these months much to encourage him. "All is going on as well as I could wish, or even as I could accomplish, were destiny at my command," he wrote on the 31st of May. "The Portsmouth engines now meet the approbation of all the authorities of the yard, and the Admiralty are so satisfied that they have given me the building of a steamship to put them in, in lieu of placing them in the oldFirefly." "Nothing," he said in a letter written a week or two later, "can exceed the perfection of the work which the Bramahs have put into theJanus'sengines." "The experimental engine at Portsmouth," he wrote on the 3rd of July, "continues to perform admirably, beating all others in the yard in point of vacuum, which, you know, is the test of power." "The engines will commence being put together in ten or fourteen days," we read in another letter dated the 10th of July; "after that we shall make rapid progress. TheJanusis now completing—that is, being coppered—and having the part of her deck laid down which was left off for the purpose of getting the boilers on board. My patent boilers will be tried by authority of the Admiralty about the 20th, and I hope for a favourable result." The trial, postponed till the 1st of August, was satisfactory. "We have tried the boilers of theJanus," he wrote on that day, "and the result is most triumphant, having, with slack firing, ten and a half pounds of water evaporated by each pound of coal." "I have just returned from Portsmouth," he had written five days before, "where I had the pleasure to find my engine exceeding even all that it had done before—the vacuum, with all the work on, being 28½, two inches above that of any other engine in the dockyard. Mr. Taplin, the chief engineer, is quite delighted with it." "Sir George Cockburn and Sir John Barrow, permanent Secretary of the Admiralty, saw my engine yesterday," he wrote on the 24th of October, concerning the machine being built by the Bramahs for theJanus; "and so did Lord Brougham; all of whom were well pleased with my explanation of its principles and the appearance of the workmanship. It is now being pulled to pieces, in order to its being sent to Chatham and set up on board theJanus, whose boilers, by my request, are again to be officially tested as to their evaporative power, and that, too, by the Woolwich authorities, whose boilers have been beaten one-third by the evaporation of mine. This request must show the Admiralty my confidence in the correctness of the former trial; for there is no doubt the Woolwich people would condemn it if they could." This second and crucial trial took place on the 9th of November, and the result exceeded alike Lord Dundonald's expectations and those of the official judges, to whom failure would have been most pleasant. "All matters as regards my engines," he wrote on the 20th of November, "are going on well. I hope soon to hear something satisfactory from the Admiralty on the subject of the boilers, respecting which they have until now pursued the most profound silence, notwithstanding the triumphant result, which has surpassed the product of the far-famed Cornish boilers in evaporative power."
Those extracts from Lord Dundonald's letters to the friend with whom he corresponded most freely will suffice to show in what temper he watched the progress of his inventions during 1844. At the close of the year he hoped that his labours to bring them into general use were now nearly at an end; but in this he was disappointed. The Woolwich authorities, who had at the time expressed their approval of the boilers, sent in an adverse report to the Admiralty, and Lord Dundonald had to wait several months before he could disprove the statements made against them; and opposition of the same sort—the common experience of nearly every inventor—encountered him at every turn, and had again and again to be overcome. His Portsmouth engine continued to work well; but in September, 1845, he learnt that a malicious trick had been resorted to, to prevent its working better. "On a recent examination of the pumps in the well," wrote Mr. Taplin, the engineer, "to our utter astonishment we found, in the middle suction pipe, an elm plug, driven in so tight that we were obliged to bore and cut it out. The plug stopped that suction pipe effectually, and from its appearance must have been there from the time the pumps were first put in motion. As proof of this, we never had such a supply of water as at present." And that is only an illustration of the obstacles, accidental or designed, that occurred to him.
By them, theJanuswas delayed for a whole year. She was to have been completed in 1844; but this was not done till the end of 1845. "I have just returned," Lord Dundonald was able to write on the 24th of December, "from a nine days' trip in theJanus, the result of which has been successful, both in regard to the properties of the engines and those of the 'lines' on which she has been constructed. Nothing can exceed the beauty of her passage through the water, without even a ripple, far less the wave which ordinary steamboats occasion." That success, however, was to be followed by a long series of disasters. The weight of theJanushad been miscalculated, and though she could proceed admirably in smooth water, she was found to lie so low that there was constant danger of her being wrecked in rough seas and bad weather. Other faults, incident to the bringing together for the first time of so much new workmanship, were also discovered. She had to be returned to dock, and fresh hindrances of every sort occurred during the two following years; each hindrance being attended by tedious correspondence or controversies with petty functionaries jealous of a stranger's interference, and only eager to bring discredit upon his work. Much discredit did result. Loud complaints were made concerning the waste of public money resulting from Lord Dundonald's experiments, and on him, of course, nearly all the blame was thrown. All this, added to his previous difficulties in securing for his boiler and engine any notice at all, was very grievous to him. Every complaint and every entreaty from him was met by a new excuse and a new reason for delay. "Ten days are always added," he said, in one letter, "and ten days yet are said to be required."
The days became weeks and the weeks months, and still theJanuswas incomplete. She was unfinished when Lord Dundonald left England for more than two years in order to fulfil the duties assigned to him as commander-in-chief of the North American and West Indian squadron, and his absence caused a final abandonment of the works.
The tedious process of her construction, however, to which only sufficient reference has here been made to serve as illustration of one phase of Lord Dundonald's life, was attended by many good results. To himself she brought only trouble and expense; but the obstacles thrown in her way and in his did not deter private adventurers from acting upon some of the principles developed in abortive attempts at her completion by public functionaries. Lord Dundonald's inventions—his revolving engine, his screw-propeller, his boiler, and his "lines of ship-building,"—have all proved useful in themselves, and have been of yet greater use in their influence upon the improved mechanism of our own generation.
To him must be attributed no slight share in the revolution that has been effected in the materials for naval warfare. Of the superiority of steamers to war-ships, he was one of the first advocates. His own rotatory engine was never extensively adopted, and was superseded by other engines which, lacking the great merit of direct action upon the paddles, that it was his object to attain, had other and greater merits of their own; but in their adoption his great object was realized, seeing that that object was not his own aggrandisement, but the development of the naval strength of England.