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Mechanics Magazine,


No. 972.]

Edited, Printed and Published by J. C. Robertson, No. 166, Fleet-street.

[Price 3d.


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VESSEL “FLETCHER'S DESPATCH," OF HULL. Sir,- Were I not well aware that the A Hot-well. most valuable and simple inventions are B Condenser. generally the most difficult of introduc C Tank to receive the water from the tion, I might long ago have despaired of hot-well. the general adoption of the Symington D Pipe to convey the water from the Method of Condensation, an invention hot-well to the tank. which, I feel fully assured, will yet E Injection-pipe. prove highly important to steam naviga F Pipes to convey the water from the tion. Of its successful application, for a tank to the refrigerating pipes. period of more than two years and a G Pipes to convey the water from the half, to the Fletcher's Despatch, of refrigerating pipes to the condenser. Hull, some notice has been already, H Refrigerating pipes. more than once, taken in the Mechanics' I Water line. Magazine ; and as no stronger evidence K Discharge pipe. than this case affords can, probably, be L Valve to shut off the connexion to adduced of the sterling merits of the in the tank. vention, and need not, indeed, be re It was but a few weeks ago that I quired, I am induced to solicit a place in learned, to my surprise, that several your pages for the following additional practical gentlemen entertained the beparticulars, and for the illustrative en lief that the plan was for the purpose gravings which accompany them.

merely of condensing steam, since it is It is now approaching to three years for the purpose of cooling the hot water since the Symington Condensing Appa

now thrown overboard, formed by the ratus was fitted to the Despatch, whose blending together of the steam and inworthy and spirited proprietor has re jection water in the common condenser, peatedly borne testimony to the advan an error which the accompanying entage he has derived from it. In letters gravings, if you favour them with a place lately received from him he says, “ I am in your Journal, cannot fail to remove. so highly satisfied with your system of

With best thanks for the favourable condensation, that I would do any thing opinions you have given of the invention, in my power to assist you; for I do I remain, Sir, think, were it universally adopted, it

Your most obedient servant, would prove a great public benefit.”

ROBERT BOWIE. Again : “ With regard to the quantity

Burr-street, Feb. 25, 1842. of tallow used, I beg leave to say, that just one-half is used, when working the new, ON THE IMPROVEMENT OF BOILERS. less than what was used

on the old

BY C. W. WILLIAMS, ESQ. plan." And further: "The Captain Sir,--The following explanation of the says, the saving of fuel is immense, and circumstances which led me to take the he hopes never again to use the old plan; prominent part I have done in enquiring for the foamentation was tremendous, and into the causes of the defects of steamthey had often to stop the engine, it being boilers may not be without its interest to impossible, at times, to get steam ; while, your readers, and will, I trust, justify me with the new plan, steam is abundant, in occupying so much of your columns and wasting.” Mr. Fletcher says, in with plans for their improvement. They conclusion: “I am perfectly satisfied, will also be a sufficient answer to the and so will any person who tries it." assertion that “engineers and boiler

Fig. 1 of the accompanying engravings makers know their business too well to is a perspective view of the Despatch, lack instruction from a pack of effershowing how far its external appearance vescent chemists and druggists ; " meanis affected by the addition of the Syming ing those chemical authorities of high ton apparatus. F. 2 is a transverse standing, whose opinions I bave cited in section of the well, showing on one side confirmation of the chemical views on a condensor:g apparatus on the ordinary which I relied. plan, od on the other the (slight) ad Being much interested ir the improveditions necessary to be made to obtain all ment of steam-vessels, from my conthe advantages of the new system. nexion with steam navigation companies,

ON THE IMPROVEMENT OF BOILERS. BY C. W. WILLIAMS, ESQ. 243 and having had a longer and more ex. undertakes that the boilers shall protended experience in the details of their vide a sufficiency of steam to work them; building and equipping than, perhaps, but what that sufficiency means, has not any individual director of a steam com been decided; and, in too many inpany in the kingdom, my attention has stances, the absence of some fixed data been uninterruptedly given to the sub on the subject has led to complaints and ject since the year 1823, when I first references, which, though they may end established a steam company, and under the disputes between the owners and took to have the first steam-vessel con makers of the engines, leave the evils of structed capable of maintaining a com a deficiency of steam or a great expendimercial intercourse across the Irish Chan ture of fuel unabated. nel, during the winter months; and If there liappen to be “steam enough," which, till then, had been considered im, the engineer's triumph is complete ; alpracticable.

though it is seldom that an account is Şince that time, my object has been taken of the quantity of fuel consumed, the imparting, through the instrumen or whether it be attended with economy tality of the most experienced ship-build or waste. If with economy, the merit of ers and steam-engine manufacturers, the the engineer is enhanced; but, if with greatest practicable degree of perfection waste, the sufferers, having no redress, and efficiency to every part of the hulls keep their grievances to themselves, and and machinery of steam-vessels.

the ledger account of fuel consumed, is the With respect to the improved state to only index to the cause of that absence which the hulls of steam-yessels have of profit which is the usual result. been brought, I refer to the papers

and Under the conviction of the danger of detailed specifications for the building of taking responsibility from the engineer, the last of those belonging to the City of although alive to the prevailing uncerDublin Steam Company, as furnished by tainty and risk, I felt, in common with myself and Mr. J. C. Shaw, the Marine other directors of steam companies, an Manager of that Company, to the Com unwillingness to interfere. From being missioners of Steam-vessels Inquiry, so deeply interested in the improvement Josiah Parkes, Esq., Civil-engineer, and of this department of steam navigation, Captain Pringle, and printed in the Ap I have watched, with no small anxiety, pendix to their Report.

the efforts of the engineers to arrive at For a practical illustration of the per some degree of certainty in what was ad. fection to which both hulls and machinery mitted, on all hands, to be the most sehave been brought, I refer to the steam rious drawback to the application of steam ship Oriental, one of those now under vessels to long sea voyages. I perceived contract with her Majesty's Government the absence of any intelligible or wellfor conveying the East India mails be founded principle in the construction of tween Great Britain and Alexandria. the boiler ;-that the part on which most

The result of this long experience is depended, appeared least understood, and the finding, that, notwithstanding the least attended to, namely, the furnace ; improved state to which the construction and that this was too often left to the and appointments of the hull and general skill (or want of it) of working boilermachinery of steam-vessels have arrived, makers or bricklayers. I saw that, algreat uncertainty and risk of failure still though the great operations of combusprevail in the department of the boiler, tion which are carried on in the furnace, and all that belongs to the use of fuel with all that belongs to the introduction and the generation of steam.

and employment of atmospheric air, were Much, certainly, has been done to among the most difficult processes within wards imparting strength to the boiler the range of chemistry, the absence of and lessening the risk of explosion. sound scientific principles still continued

The most experienced engineers are, to prevail; yet on these depend the exhowever, still unable to decide, previously tent or perfection of the combustion in to trial, either as to the quantity of fuel our furnaces. that will be consumed or of steam gene

Years were still passing away, and, rated.

while every other department was fast It is true, the engineer, who under approaching to perfection, all that betakes the construction of the engines, also longed to the combustion of fuel—the

production of smoke—and the wear and terfere and share the risk of failure was tear of the furnace part of the boiler, re put an end to by an imperious necessity. mained in the same status quo of uncer I was brought to the conclusion, that, to tainty and insufficiency; and, although remain any longer a mere spectator of the recourse to new plans and new smoke- those abortive efforts towards improveburning expedients continued, and every ment, and, in all cases, to wait the result year brought fourth a new batch of in- of trial, before it could be ascertained fallible remedies for “consuming smoke whether a new boiler was to turn out and economizing fuel," success and cer good or bad, wasteful or economie, was tainty seemed as unattainable as ever, inconsistent, if not with the progress of although there appeared such an abund steam navigation, at least with the most ance of labourers in the field of specu vital interests of those for whom I was lation and invention.

acting In fact, things seemed almost retro This ultima ratio for interference, grading into greater doubt and want of necessity, became also the more urgent, system, rather than advancing to perfec- since long sea voyages have been contion, or even keeping pace with the im- templated. The determination to exprovements of the hulls and engines; amine for myself and exercise my own and many of the furnaces, both of marine judgment was forced upon me by the and land boilers, constructed within the failure of the steam-ship the Liverpool

, last few years, with their arrangements on her first voyage to New York. I saw, for effecting a perfect or economical use that the owners and managers of steam of fuel, exhibit greater violations of che companies could be in no worse position mical truths, and a greater departure (as to risk or responsibility, touching the from the principles on which nature pro boiler department) from their interferceeds, than any preceding ones which ence, than that in which they were placed have come under my observation. under the circumstances of non-inter

With respect to the all-important con ference. siderations, the quantity of fuel required, The errors which led to the failure of or the most judicious mode of effecting the first voyage of the Liverpool were its combustion, the problem, -whether erroneously attributed to thie' interferthe boiler (for the furnace is never spoken ence of the managers or directors, and of apart from the boiler) would generate many unfounded reports were circu; more or less steam-produce more or less lated. The failure was first attributed smoke-or consume more or less fuel to “an expensive trying of experi-still remained to be decided by the ments.” Again, to argumentum ad rem, alone-experiment; try the celebrated Cornish principle of and, if unsuccessful, the evil would be slow combustion, in order to burn the irremediable, and the owners doomed to smoke.” Again, and by the same party, eat the bread of disappointment, if not

to a system of “excessive firing," and of loss. The result of a boiler, on being over firing,(the very reverse of the tried, turning up a trump, and giving Cornish principle). It is only necessary “plenty of steam,” with a small con to state, that no interference with the sumption of fuel, was, indeed, tanta engineers, and no experiment of any mount to a profitable employment of the kind, was made or attempted; on the vessel

, while the reverse was inevitably contrary, a rigid determination prevailed attended with a succession of alterations, against interfering with the makers of and, most likely, of loss to the specu the boilers; and in fact, no injury or lation.

accident did occur to the boilers, much These were the considerations which

less occasion her putting back to Cork. operated with me when adding my mite Among the proofs of this stationary of to the inquiry, an inquiry which, it is retrograding systein I shall adduce the manifest, will not be originated by the boilers originally placed in the Liverpool

. "working boiler-maker or bricklayer;" I shall give the details of those boiler and, if I have not perfected the system and the several efforts, on the part of the which so loudly calls for improvement, engineers, to remedy' what I will show I have, at least, directed the inquirer into were inherent defects, and instances of the right road.

contempt for those chemical principles On my own part, the reluctance to in on which combustion and the right use

an attempt " to


245 of fuel alone depend. I will show, that has been no lack of works on the other the cause of that wasteful expenditure of and older branches of ornamental paintcoals which marked the first voyage of ing, for almost every month produces the Liverpool was induced by the origi- something new, although less useful to nal mal-construction of the boilers, with painters in general, in consequence of their twenty furnaces—and by the injudi- the prevailing taste of the public. Where cious mode of placing them in the ves there is one person employed in the other sel, with the facility thus afforded to branches of ornamental painting, there mismanagement in their working; and are hundreds employed in imitating that the latter, combined with the ab woods and marbles, and no doubt many sence of sound judgment, in this in more would be employed if the art were stance, on the part of those in command, better understood. It is at once a recomand an unnecessary and wasteful expen mendation to permanent and lucrative diture of fuel, in the teeth of written situations, to be able to grain in the most instructions, at a time when common modern and improved manner.

Theresense would have suggested its being fore, as this knowledge of graining is of economised and reserved, were the direct so much importance to those who are causes of the failure which attended the learning the art of house-painting, I first attempt of that vessel to cross the trust that I shall not be thought preAtlantic. I will, from these facts, show, sumptuous in endeavouring, after a practhat, however well judged and consi tical experience, in London and Edinderate may be the plans of the directors burgh, of seventeen years, to place withof stear companies, however spirited in the reach of all, what that experience may be their efforts to have every thing induces me to believe to be the right as perfect and efficient as money or deter- principles of working.” mination can make it, yet still the compa Mr. Moxon then proceeds to give some rative efficiency of a steam-vessel—the general directions to be observed in imi. satisfaction and patronage of the public- tating woods, of a most pertinent and and thegeneral success of the speculation practical character, with particular inmust mainly depend on the manner in structions for the production of mahowhich the engineer performs his part. gany, maple-wood, rose-wood, satinI am, Sir, yours, &c.

wood, wainscoat, &c.; these being fol. C. W. WILLIAMS. lowed 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 speciTHE GRAINER'S GUIDE, BY

mens executed by hand-brush in the MOXON, LONDON,

most simple and practical manner; inA folio volume, under this title, has deed, so much simplified, that any painter just appeared, which is eminently qualified of ordinary capacity may, (by applicato supply a desideratum which has long tion,) in the course of a few weeks' pracbeen felt by a very large class of practical tice, be astonished at his own advanceornamental painters, and is well calcu ment. More elaborate or more ghlylated to correct the false taste which has finished specimens would, no doubt, be too largely characterized most of our more captivating to the inexperienced ; imitations of woods and marbles. In his but those who understand any thing introductory remarks Mr. Moxon ob about graining will at once perceive the serves, that "imitation of woods and advantage to be derived from copying marbles having now become a very these simple patterns." fashionable style of decoration, and being In his general remarks on imitating so well adapted to the character of our marbles, Mr. Moxon observes, that “the buildings, it has long been a matter of reason why marbles are more difficult to surprise to me that no one has hitherto imitate than woods is, that few people attempted, (at least with any considerable possess a good eye for 'colour. I have degree of success,) to lessen the diffi seen some of the very finest wood-grainers culties that house-painters have to con commence to imitate Sienna marble with tend with in learning to imitate woods a handful of small pencils, and more fine and marbles in a skilful manner. There colours than Rubens would have required


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