Mechanics' Magazine, MUSEUM, REGISTER, JOURNAL, AND GAZETTE. No. 972.] SATURDAY, MARCH 26, 1842. Edited, Printed and Published by J. C. Robertson, No. 166, Fleet-street. THE "DESPATCH," OF HULL, Fig. 1. [Price 3d. THE SYMINGTON METHOD OF CONDENSATION, AS APPLIED TO THE STEAMVESSEL "FLETCHER'S DESPATCH," OF HULL. Sir,-Were I not well aware that the most valuable and simple inventions are generally the most difficult of introduction, I might long ago have despaired of the general adoption of the Symington Method of Condensation, an invention which, I feel fully assured, will yet prove highly important to steam navigation. Of its successful application, for a period of more than two years and a half, to the Fletcher's Despatch, of Hull, some notice has been already, more than once, taken in the Mechanics' Magazine; and as no stronger evidence than this case affords can, probably, be adduced of the sterling merits of the invention, and need not, indeed, be required, I am induced to solicit a place in your pages for the following additional particulars, and for the illustrative engravings which accompany them. It is now approaching to three years since the Symington Condensing Apparatus was fitted to the Despatch, whose worthy and spirited proprietor has repeatedly borne testimony to the advantage he has derived from it. In letters lately received from him he says, "I am so highly satisfied with your system of condensation, that I would do any thing in my power to assist you; for I do think, were it universally adopted, it would prove a great public benefit." Again: "With regard to the quantity of tallow used, I beg leave to say, that just one-half is used, when working the new, less than what was used on the old plan." And further: "The Captain says, the saving of fuel is immense, and he hopes never again to use the old plan; for the foamentation was tremendous, and they had often to stop the engine, it being impossible, at times, to get steam; while, with the new plan, steam is abundant, and wasting." Mr. Fletcher says, in conclusion: "I am perfectly satisfied, and so will any person who tries it." Fig. 1 of the accompanying engravings is a perspective view of the Despatch, showing how far its external appearance is affected by the addition of the Symington apparatus. F. 2 is a transverse section of the ull, showing on one side a condensing apparatus on the ordinary plan, d on the other the (slight) additions necessary to be made to obtain all the advantages of the new system. A Hot-well. B Condenser. C Tank to receive the water from the hot-well. D Pipe to convey the water from the hot-well to the tank. E Injection-pipe. F Pipes to convey the water from the tank to the refrigerating pipes. G Pipes to convey the water from the refrigerating pipes to the condenser. H Refrigerating pipes. I Water line. K Discharge pipe. L Valve to shut off the connexion to the tank. It was but a few weeks ago that I learned, to my surprise, that several practical gentlemen entertained the belief that the plan was for the purpose merely of condensing steam, since it is for the purpose of cooling the hot water now thrown overboard, formed by the blending together of the steam and injection water in the common condenser, an error which the accompanying engravings, if you favour them with a place in your Journal, cannot fail to remove. With best thanks for the favourable opinions you have given of the invention, I remain, Sir, Your most obedient servant, Burr-street, Feb. 25, 1842. ON THE IMPROVEMENT OF BOILERS. Sir, The following explanation of the circumstances which led me to take the prominent part I have done in enquiring into the causes of the defects of steamboilers may not be without its interest to your readers, and will, I trust, justify me in occupying so much of your columns with plans for their improvement. They will also be a sufficient answer to the assertion that "engineers and boilermakers know their business too well to lack instruction from a pack of effervescent chemists and druggists;" meaning those chemical authorities of high standing, whose opinions I have cited in confirmation of the chemical views on which I relied. Being much interested in the improvement of steam-vessels, from my connexion with steam navigation companies, ON THE IMPROVEMENT of boilers. and having had a longer and more ex tended experience in the details of their building and equipping than, perhaps, any individual director of a steam company in the kingdom, my attention has been uninterruptedly given to the subject since the year 1823, when I first established a steam company, and undertook to have the first steam-vessel constructed capable of maintaining a commercial intercourse across the Irish Channel, during the winter months; and which, till then, had been considered im, practicable. Since that time, my object has been the imparting, through the instrumentality of the most experienced ship-builders and steam-engine manufacturers, the greatest practicable degree of perfection and efficiency to every part of the hulls and machinery of steam-vessels. With respect to the improved state to which the hulls of steam-vessels have been brought, I refer to the papers and detailed specifications for the building of the last of those belonging to the City of Dublin Steam Company, as furnished by myself and Mr. J. C. Shaw, the Marine Manager of that Company, to the Commissioners of Steam-vessels Inquiry, Josiah Parkes, Esq., Civil-engineer, and Captain Pringle, and printed in the Appendix to their Report. For a practical illustration of the perfection to which both hulls and machinery have been brought, I refer to the steamship Oriental, one of those now under contract with her Majesty's Government for conveying the East India mails between Great Britain and Alexandria. The result of this long experience is the finding, that, notwithstanding the improved state to which the construction and appointments of the hull and general machinery of steam-vessels have arrived, great uncertainty and risk of failure still prevail in the department of the boiler, and all that belongs to the use of fuel and the generation of steam. Much, certainly, has been done towards imparting strength to the boiler and lessening the risk of explosion. The most experienced engineers are, however, still unable to decide, previously to trial, either as to the quantity of fuel that will be consumed or of steam generated. It is true, the engineer, who undertakes the construction of the engines, also 243 BY C. W. WILLIAMS, ESQ. undertakes that the boilers shall provide a sufficiency of steam to work them; but what that sufficiency means, has not been decided; and, in too many instances, the absence of some fixed data on the subject has led to complaints and references, which, though they may end the disputes between the owners and makers of the engines, leave the evils of a deficiency of steam or a great expenditure of fuel unabated. If there happen to be "steam enough," the engineer's triumph is complete; although it is seldom that an account is taken of the quantity of fuel consumed, or whether it be attended with economy or waste. If with economy, the merit of the engineer is enhanced; but, if with waste, the sufferers, having no redress, keep their grievances to themselves, and the ledger account of fuel consumed, is the only index to the cause of that absence of profit which is the usual result. Under the conviction of the danger of taking responsibility from the engineer, although alive to the prevailing uncertainty and risk, I felt, in common with other directors of steam companies, an unwillingness to interfere. From being so deeply interested in the improvement of this department of steam navigation, I have watched, with no small anxiety, the efforts of the engineers to arrive at some degree of certainty in what was admitted, on all hands, to be the most serious drawback to the application of steam vessels to long sea voyages. I perceived the absence of any intelligible or wellfounded principle in the construction of the boiler;-that the part on which most depended, appeared least understood, and least attended to, namely, the furnace; and that this was too often left to the skill (or want of it) of working boilermakers or bricklayers. I saw that, although the great operations of combustion which are carried on in the furnace, with all that belongs to the introduction and employment of atmospheric air, were among the most difficult processes within the range of chemistry, the absence of sound scientific principles still continued to prevail; yet on these depend the extent or perfection of the combustion in our furnaces. Years were still passing away, and, while every other department was fast approaching to perfection, all that belonged to the combustion of fuel-the production of smoke-and the wear and tear of the furnace part of the boiler, remained in the same status quo of uncertainty and insufficiency; and, although the recourse to new plans and new smokeburning expedients continued, and every year brought fourth a new batch of infallible remedies for "consuming smoke and economizing fuel," success and certainty seemed as unattainable as ever, although there appeared such an abundance of labourers in the field of speculation and invention. In fact, things seemed almost retrograding into greater doubt and want of system, rather than advancing to perfection, or even keeping pace with the improvements of the hulls and engines; and many of the furnaces, both of marine and land boilers, constructed within the last few years, with their arrangements for effecting a perfect or economical use of fuel, exhibit greater violations of chemical truths, and a greater departure from the principles on which nature proceeds, than any preceding ones which have come under my observation. With respect to the all-important considerations, the quantity of fuel required, or the most judicious mode of effecting its combustion, the problem,-whether the boiler (for the furnace is never spoken of apart from the boiler) would generate more or less steam-produce more or less smoke or consume more or less fuel -still remained to be decided by the argumentum ad rem, alone-experiment; and, if unsuccessful, the evil would be irremediable, and the owners doomed to eat the bread of disappointment, if not of loss. The result of a boiler, on being tried, turning up a trump, and giving "plenty of steam," with a small consumption of fuel, was, indeed, tantamount to a profitable employment of the vessel, while the reverse was inevitably attended with a succession of alterations, and, most likely, of loss to the speculation. These were the considerations which operated with me when adding my mite to the inquiry, an inquiry which, it is manifest, will not be originated by the "working boiler-maker or bricklayer;" and, if I have not perfected the system which so loudly calls for improvement, I have, at least, directed the inquirer into the right road. On my own part, the reluctance to in terfere and share the risk of failure was put an end to by an imperious necessity. I was brought to the conclusion, that, to remain any longer a mere spectator of those abortive efforts towards improvement, and, in all cases, to wait the result of trial, before it could be ascertained whether a new boiler was to turn out good or bad, wasteful or economic, was inconsistent, if not with the progress of steam navigation, at least with the most vital interests of those for whom I was acting. This ultima ratio for interference, necessity, became also the more urgent, since long sea voyages have been contemplated. The determination to examine for myself and exercise my own judgment was forced upon me by the failure of the steam-ship the Liverpool, on her first voyage to New York. I saw, that the owners and managers of steam companies could be in no worse position (as to risk or responsibility, touching the boiler department) from their interference, than that in which they were placed under the circumstances of non-interference. The errors which led to the failure of the first voyage of the Liverpool were erroneously attributed to the interference of the managers or directors, and many unfounded reports were circulated. The failure was first attributed to an expensive trying of experiments." Again, to an attempt "to try the celebrated Cornish principle of slow combustion, in order to burn the smoke." Again, and by the same party, to a system of "excessive firing," and 66 over firing," (the very reverse of the Cornish principle). It is only necessary to state, that no interference with the engineers, and no experiment of any kind, was made or attempted; on the contrary, a rigid determination prevailed against interfering with the makers of the boilers; and in fact, no injury or accident did occur to the boilers, much less occasion her putting back to Cork. Among the proofs of this stationary or retrograding system I shall adduce the boilers originally placed in the Liverpool. I shall give the details of those boilers, and the several efforts, on the part of the engineers, to remedy what I will show were inherent defects, and instances of contempt for those chemical principles on which combustion and the right use MOXON'S GRAINER'S GUIDE. of fuel alone depend. I will show, that the cause of that wasteful expenditure of coals which marked the first voyage of the Liverpool was induced by the original mal-construction of the boilers, with their twenty furnaces-and by the injudicious mode of placing them in the vessel, with the facility thus afforded to mismanagement in their working; and that the latter, combined with the absence of sound judgment, in this instance, on the part of those in command, and an unnecessary and wasteful expenditure of fuel, in the teeth of written instructions, at a time when common sense would have suggested its being economised and reserved, were the direct causes of the failure which attended the first attempt of that vessel to cross the Atlantic. I will, from these facts, show, that, however well judged and considerate may be the plans of the directors of steam companies, however spirited may be their efforts to have every thing as perfect and efficient as money or determination can make it, yet still the comparative efficiency of a steam-vessel-the satisfaction and patronage of the public and the general success of the speculationmust mainly depend on the manner in which the engineer performs his part. I am, Sir, yours, &c. C. W. WILLIAMS. THE GRAINER'S GUIDE, BY CHARLES MOXON, LONDON. A folio volume, under this title, has just appeared, which is eminently qualified to supply a desideratum which has long been felt by a very large class of practical ornamental painters, and is well calculated to correct the false taste which has too largely characterized most of our imitations of woods and marbles. In his introductory remarks Mr. Moxon observes, that "imitation of woods and marbles having now become a very fashionable style of decoration, and being so well adapted to the character of our buildings, it has long been a matter of surprise to me that no one has hitherto attempted, (at least with any considerable degree of success,) to lessen the difficulties that house-painters have to contend with in learning to imitate woods and marbles in a skilful manner. There 245 has been no lack of works on the other and older branches of ornamental painting, for almost every month produces something new, although less useful to painters in general, in consequence of the prevailing taste of the public. Where there is one person employed in the other branches of ornamental painting, there are hundreds employed in imitating woods and marbles, and no doubt many more would be employed if the art were better understood. It is at once a recommendation to permanent and lucrative situations, to be able to grain in the most modern and improved manner. Therefore, as this knowledge of graining is of so much importance to those who are learning the art of house-painting, I trust that I shall not be thought presumptuous in endeavouring, after a practical experience, in London and Edinburgh, of seventeen years, to place within the reach of all, what that experience induces me to believe to be the right principles of working." Mr. Moxon then proceeds to give some general directions to be observed in imitating woods, of a most pertinent and practical character, with particular instructions for the production of mahogany, maple-wood, rose-wood, satinwood, wainscoat, &c.; these being followed by beautifully-executed specimens of each. The author remarks, that "the chief object in view is to instruct those who are desirous of becoming good grainers, by placing before them specimens executed by hand-brush in the most simple and practical manner; indeed, so much simplified, that any painter of ordinary capacity may, (by application,) in the course of a few weeks' practice, be astonished at his own advancement. More elaborate or more highlyfinished specimens would, no doubt, be more captivating to the inexperienced; but those who understand any thing about graining will at once perceive the advantage to be derived from copying these simple patterns." In his general remarks on imitating marbles, Mr. Moxon observes, that "the reason why marbles are more difficult to imitate than woods is, that few people possess a good eye for 'colour. I have seen some of the very finest wood-grainers commence to imitate Sienna marble with a handful of small pencils, and more fine colours than Rubens would have required |