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THE GREAT EASTERN.
Sept. 7, Noon.

After

a trial of speed. The first thing is to get the ship safely out of the Thames; the next will be to get her comfortably round to Portland. that she will start upon her "trial trip," and then will be the time for putting her to all necessary tests.

The experiment of to-day has sufficiently shown

THE great ship having cast anchor off Parfleet
(between Erith and Gravesend) we can do no
better, we think, than gossip for a few minutes
with our readers (for one can only gossip on ship that the practical handling of ships of this im-
board) respecting the event which has kept both
banks of the Thames thronged with cheering Careful observation has enabled us to assure our-
size will present no great difficulties.
human creatures for several hours this morn-selves that, at low speeds, at any rate, the Great

ing.

It having been our good fortune to receive one of the very few invitations issued for this passage of the Great Eastern down the river, we embarked last night "by the light of the moon," and found that the ship really was to undertake the passage, weather permitting, early to-day. In both engine-rooms all was ready for the purpose; the last few barge-loads of stores were alongside, and were being rapidly run on board by the steam cranes; the coaling was completed, as far, that is, as it was intended to coal at Deptford; the rain and wind of the day had subsided; and the captain announced that nothing short of a gale would defer the departure of the morning.

Occasion was thus afforded for speculation upon the prospects we had of getting well down the river to-day, and this speculation we quietly pursued while pacing the "great deck" (in a very pleasant mixture of moonlight and starlight) till the hours grew nearly to their largest. As grounds for apprehension we had, first, the fact that several very awkward bends and shallows would present themselves almost as soon as our moorings were slipt; and secondly, we had the further fact that on the first trial of a stupendous experiment mischances and miscarriages of some kind may usually be looked for with confidence. We also knew that the engines of our ship were of an unprecedented size, and were really about to be put upon their trial for the first time. On the other hand we knew that in Mr. Atkinson we were to possess the skilfullest of pilots-in Captain Harrison the ablest of captains-and in the engineers on board some of the cleverest practical men of the day. We further had the satisfaction of learning that the working of both the paddle and the screw engines were to be placed under the personal control of Mr. Scott Russell, and of him alone. This last arrangement was calculated to inspire great confidence, because no one could possibly have a higher sense than Mr. Russell of the importance of handling the engines carefully on this great occasion, and no one could have a warmer interest in their successful operation. On the whole, therefore, we "turned in" contented with our anticipations of the morrow's

work.

The result, thus far, has amply justified our expectations. By six o'clock this morning we were on deck, and found good reason to expect an early start. By half past seven the tugs had hold of us, the moorings were slipt, and amid many cheers the monster moved off. Without the slightest mishap, and almost without a stoppage, this huge structure has been brought in three hours to this spot, where she has room to swing with the tide, and make herself "at home," for the first time. From the moment of starting, all eyes have been turned upon the pilot, the captain, and Mr. Russell, the two former of whom have performed their duty from the paddle-boxes as usual, while Mr. Russell has kept himself stationed at the engine-room telegraphs, upon the paddle-bridge, working the two engines conjointly or separately, jas seemed best to him-always, of course, supplying the speed required by the pilot. Neither engine has, however, run beyond very low velocities. Twenty revolutions per minute is, we believe, the greatest speed which the screw engine has been allowed to attain, and the paddle engine has been limited to about seven or eight. It is no part of the proprietors' present purpose to attempt anything like

mense

Eastern will steer well. Whether a high speed will interfere with her excellence in this respect can hardly be said; let us hope not. Then, as to the communication of the captain's instructions along her great length, very little difficulty has been experienced, notwithstanding the intricacy of the navigation in this instance; indeed, the only difficulty that occurred was that of getting the tugs a-head to do exactly what was required in all cases; no obstruction whatever interfered with the guidance of the helmsmen. Nor is this owing to the adoption of Mr. Lungley's admirable steering-signal apparatus, for through an error in the arrangement of one of the parts this will not be placed at the captain's service until to-morrow. The apparatus will, however, reduce this part of the vessel's management to the simplest form possible; for by it the captain will be able to speak to the eye of the helmsman-no matter how far off he may be-all but as quickly and distinctly as he could speak to his ear when at his side. We hope to see the apparatus in operation on our way to the Nore to-morrow.

We must not omit to mention the admirable precision with which Mr. Suffield's engine-room telegraphs have worked to-day. We have made them the objects of our special observation, and must say that their operation has been most satisfactory. In addition to our own testimony we may also add that of Mr. Scott Russell, who, we have already said, worked them himself throughout, and who has subsequently assured Mr. Suffield that they have given him entire satisfaction; have proved themselves, in a word, "reliable."

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To-morrow, the weather being moderate, we proceed to the Nore. We shall there, probably, have another opportunity of reporting progress, but not, we fear, in time for our next number. The ship, and all in whose hands she now is, deserve success, and we sincerely wish it them.

Thursday Noon, Off Southend.

We are now running down to the Nore under engines at "half-speed," the paddles making 81 revolutions, and the screw 28. The theoretical speed of the ship (neglecting slips) is therefore about 13 knots; the real speed is 2 or 3 knots less probably, as the screw and wheels are insufficiently immersed to produce any near approximation to the theoretical result. The crew and company have saluted the ship, giving also three cheers, and one cheer more for Mr. Scott Russell and also for Mr. Brunel. All on board are delighted with the complete success that has thus far attended the ship's progress.

[We have at the last moment received another communication from our colleague (dated from Sheerness), stating that the ship ran down Long Reach most handsomely after the tugs were cast off. There is scarcely any perceptible vibration produced in the ship, except near the stern, and even there it is but very slight. She will have started for Portland before these lines appear.]

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THE CHEMISTRY OF CAST-IRON.

By F. A. ABEL, Esq., Chemist of the War Department. THE following paper on the " Results of the chemical examination of iron, and the materials employed in its production," is taken from the bluebook on cast-iron which has just been issued, and which is discussed in a leading article on another page of this Number.

sult of the analytical examinations of each set of A special report has been drawn up on the resamples received from the various works. To facilitate a comparison between the composition of the irons, ores, &c., tabulated statements have been prepared of the following description:

Table I. embraces the numerical results obtained in the examination of the samples of iron. Table II. exhibits the per-centages of the most important constituents of the various ores; and,

Table III. includes, similarly, the principal results obtained in the examination of the fuels and fluxes.

The following are a few remarks which have suggested themselves upon an inspection of these tabulated results:

The following table, giving the theoretical The specimens of iron prepared from the ores speeds of both the paddles and the screw, gradu-of the Northern District and from the Forest of ated according to the number of revolutions made Dean are remarkably free from phosphorus. This in each case, will be interesting. Experiments is readily explained by the very high quality of made this morning show that these theoretical these ores, which are almost perfectly free from numbers may be taken as practically correct, phosphoric acid. The considerable per-centage of the slips in the two cases balancing each silicon contained in a great number of the speciother :mens of iron alluded to is perhaps less easy of

explanation. A reference to the composition of the specimen of Ulverston (Hæmatite) iron, given in the appendix to this Report, which was smelted with charcoal, and only contains 0.59 per cent. of silicon, would appear, however, to indicate definitely that the high proportions of silicon must be ascribed to the employment of hot-blast in the reduction of the iron at those works.

The products of the ores from South Staffordshire and South Wales which have been examined are, with two or three exceptions, of excellent chemical quality. Only three instances occur in these divisions of the series of iron samples (out of twenty-six samples from eight different works), in which the amount of silicon reaches two per cent. The samples from the Netherton and Old Hill Works (South Staffordshire) and the Blaenavon and Pontypool Works (South Wales), in the preparation of which cold-blast is specified as having been employed, the silicon, in only two instances (out of thirteen varieties of iron), slightly exceeds in amount 1 15 per cent.

The proportions of phosphorus and sulphur in

irons from the ores of these districts are also in

(the East End Iron Works) are, moreover, stated to have been produced with cold blast. The North Staffordshire ore, used at the Goldendale Works, contains nearly 15 per cent. of phosphoric acid, and the proportion of phosphorus in the iron produced from it just exceeds one per cent.

A general inspection of the results obtained in the examination of the samples of ores and of the iron varieties produced from them appears to justify the following conclusions, upon which metallurgic chemists are now tolerably well agreed :— 1. The proportion of silicon in iron is much less influenced by the constitution or quality of the ores employed than by the conditions of smelting. A reference to the composition of the Northamptonshire ores and iron samples (particu. larly those from the Heyford Works), indicates that under certain circumstances, among which may probably be included a deficiency in alumina in the ore or the flux employed, an ore containing much silica is very liable to furnish a highly siliceous iron.

2. The proportion of sulphur existing even in considerable in the majority of the samples ex- light grey pig-iron is never so considerable as to amined. In the case of three only (out of twenty-exert an appreciable influence on the properties of six) does the amount of sulphur reach to 1-10th the metal; and none of the descriptions of per cent., and the phosphorus amounts to less than British ores which have been examined in connec05 per cent. in twenty instances; of the other tion with this report contain an amount of sulphur six, three contain less than 0.6 per cent.; one from compound sufficient to exert any prejudicial inthe Old Hill Works contains 0.63 per cent., fluence on the quality of iron produced from them. and two samples from Brierly Hill Works 3. The proportion of phosphorus in iron is, in contain 0.63 and 0.72 per cent. The ores great measure, determined by the per-centage of employed at the latter works contain some- phosphoric acid in the ore employed, while, at the what high per centages of phosphoric acid, the same time, it is probably to some extent regulated effects of which on the composition of the iron by the temperature at which the reduction is produced are, therefore, clearly traced. The effected (i. e., by the employment of hot or cold per-centages of phosphoric acid in the ores blast). used at the Old Hill Works (particularly in the "Balls," Bilston), are also higher than those in most of the ores used at the remaining South Staffordshire Works; and its influence on the quality of the product is, to some extent, shown by a reference to the composition of some of the

irons from those works.

That the proportion of phosphorus in the iron is not always determined by the proportion of phosphoric acid existing in the ore employed need, however, be scarcely pointed out; the fact may be exemplified by reference to some of the samples of iron from the works last alluded to, and to the iron from the Lays Works, near Dudley, in which the per-centage of phosphorus is small, while the phosphoric acid in the ore is comparatively high. The circumstance that the proportion of phosphorus in all the samples of iron from the Blaenavon Works is small, while several of the ores employed contain considerable quantities of phosphoric acid, is probably to be ascribed to the employment of cold blast in the reduction of the iron at those works.

The various ores examined, if classed according to the per-centage of phosphorus in the iron re duced from them, would stand in the following order :

No. 1. Northern District and Forest of Dean ores, used by the Whitehaven, Weardale, and Parkend Works.

No.

No.

No.

No.

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5. Cleveland ores, used at the South Bank

and Stockton Works.

metal.

The Oolitic ores and the clay ironstones employed at the works in the North Midland and North Staffordshire districts, from which specimens were submitted, as also the ochrey brown ironstones It will scarcely be out of place to conclude employed at the Northamptonshire Works, conthese few remarks on the results of the analytical examinations, with some notice of the very contain proportions of phosphoric acid, which are siderable difference observed in the structure of more considerable than those existing in the greater number of the other ores examined. Thus, many of the samples of iron analysed, and parthe ore employed at the South Bank Furnaces ticularly in the physical condition of the so-called contains nearly two per cent. of phosphoric acid; graphite, as exhibited by fresh fractures of the that used at the Stockton Works contains upwards In some instances a grey iron containing a per-centage of graphite similar to, or even of 1.5 per cent., and very nearly the same amount higher than, that in a second example, exhibited a exists in one of the ores at the Butterley Works, dense compact structure, while that of the other and in that employed at the Goldendale Works sample was open-grained, and showed the exis(North Staffordshire). The proportions of phos-tence of the graphite in large and distinct scales. phorus in the various samples of iron from these These modifications in the structure of pig-iron sources exceed one per cent., excepting in one are so well known, that they are only alluded to sample from the Butterley Works, in which, howbecause it is to them that must undoubtedly be ever, it amounts to 072 per cent. ascribed, in many instances, the apparent discreThe samples of iron produced from Northamp-pancies (which may be noticed by a comparison of tonshire ores also contain more than one per cent. the results included in this report) between the of phosphorus, the proportions of phosphoric acid chemical quality of a sample of iron and the in the ores are, however, not quite as high as those results which it has furnished when submitted to last alluded to, amounting to 0.84 and 1:03 per mechanical tests. It is self-evident that a sample cent. The samples of iron from one of the works of grey iron, compact and uniform in structure,

may resist the application, for example, of a much more considerable tensile strain, than one which is of higher chemical quality (e. g., containing less silicon or phosphorus), but of which the structure is comparatively open and irregular. There is little doubt, also, from the results of numerous experiments which have been made in this direction, that the effect of adding considerably to the strength of some kinds of cast-iron, by repeatedly re-melting them, is, within certain limits, due to no important chemical change effected in the iron, but to the gradual production of a more thoroughly uniform mass, in which the graphite carbon has gradually undergone a material change in its state of aggregation.

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me,

and the correspondence on the subject being voluminous, I have the honour now to lay before you in a simple form the principal facts.

In 1854 I discovered a method of constructing cannon (or other tubes) whereby greater strength can be obtained from the same thickness of the same metal than by any other known method; in September I offered to the Duke of Newcastle to communicate my plan to any person his Grace wished, who was capable of understanding the subject, bat was referred to the Ordnance Select Committee; in November I went, at considerable expense, to Constantinople and Balaclava, and tried in vain to persuade Lord Lyons to use my invention for some heavy guns to destroy the sea-forts of Sevastopol, and for some huge howitzers to shell that place from steamers at a distance of two or three miles. On my return to England in January, 1855, you may recollect, Sir, that you were good enough to give me a note of introduction to the Duke of Newcastle, who then imme. diately received me, and put me in communication with Colonel Lefroy on the subject. From this scientific officer, however, I learnt with much regret, that he personally could do nothing to recommend my plans or the reverse, but that they must be laid before the Ordnance Select Committee. Knowing the uselessness of approaching that body utility rested on mathematical calculations, I at with a novel invention, the only proof of whose once set to work to get a sample gun made. Having already been at expense in going to the East, and being about to enter on a course of costly experiments, I now took out a patent (dated the 27th February, 1855). Before attempting ceive, Sir, that I had offered my invention to the thus to ensure any profit to myself, you will per trouble to press its acceptance on it. I was excountry as a free gift, and given myself much tremely fortunate in my choice of a manufacturer, and by the end of March the Butterley Company had completed for me an 18-pounder gun, which was tested near their works in Derbyshire, and whose strength exceeded my expectations. applied to Lord Panmure for leave to have it tested at Woolwich by the Ordnance Select Committee, but as a communication between the War Office and the Committee, through the Lieutenant General of Artillery, required six or seven weeks. I had the gun altered for further private experi

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ments. It was an excellent 18-pounder gun, fully equal to the service gun, though little more than one-third its weight: I had the bore enlarged to the size of a 21-pounder, reducing the thicknes of metal where the greatest strength is requisite to 2 inches. As the thickness of an ordinary 24-pounder is there 64 inches, I can have had n expectation that mine would be equally strong I only wished to see how strong it was Having by the middle of May obtained permission to sen the gun to Woolwich, I did so, and explained t

the present one. The Committee of 1854 was differently constituted from

the Committee how I had altered and weakened it. It was tried, and after being fired several rounds with 4 lbs., 5 lbs. and 6 lbs. of powder, a solid 24-pounder shot, and two wads, it absolutely twice bore a charge of 8 lbs. of powder and the shot and wads, bursting at the third round. To my astonishment, the Committee reported that guns so constructed could never be considered safe."

contractors for the use of the Government, or else royalty due to me. That wrought iron is inferior
to purchase my patent. The cannon on which I is acknowledged by Sir W. Armstrong himself. He
claim a royalty are now known as Armstrong | tried it, Captain Younghusband says, and aban-
guns, but their strength is obtained by the plan I doned it for steel. That he did not afterwards
advocate, as you will at once perceive, Sir, by abandon steel, because it failed, is proved by his
comparing the published accounts of each.
concluding words when writing to the Times
Provisional Specification Provisional Specification about his first gun, which was made with a steel

left by W. G. Arm-
strong at the Office of
the Commissioners of
Patents, with his Peti-
tion, on the 11th Feb.,
1857.

Some scientific members having been added to the Committee by the Duke of Newcastle, and having been invited by the President to sit (in consequence of representations, which have secured me the hostility of the Committee ever since), II, WILLIAM GEORGE early in June presented the calculations on which I formed my theory, and obtained leave to send another gun for trial. The calculations were reported on by a mathematician, Mr. Heather, and declared inapplicable to cannon. The gun, however, a 9-pounder, was most completely successful. A cast-iron service gun and a brass service gun of the same calibre were fired round for round

with it, with the same charge of powder, so long as they stood. All three were fired :—

ARMSTRONG, of Newcas-
tle-upon-Tyne, in the
County of Northumber-
land, Civil Engineer, do
hereby declare the nature
of the said Invention for
Improvements in Ord
nance,' to be as follows:-
"The improvements re-
late, firstly, to forming
guns with the internal
tube or cylinder of

2 rounds with 8 lbs. of powder, 2 shots and 1 wad. wrought iron or gun me

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3 lbs.

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So great was the endurance of this gun, that the experiment lasted nineteen months, consequently was not officially reported till 1857. 6-pounder was then ordered to be made at the Government foundry at Woolwich, further to test Lay plan. The gun has been made, but, I believe, bas not been fired to this day!! Meanwhile I have made many private experiments.

In 1855, Mr. Robert Mallet, assisted by an emiDent mathematician, Dr. Andrew Hart, of Trinity College, Dublin, planned the construction of cannon on the same principle I advocate. He obtained the sanction of Lord Palmerston to

expend a large sum of public money to test the
truth of the theory; the Ordnance Select Com-
mittee having reported it unsound. I could bring
forward, if necessary, many more proofs that the
value of this method of manufacture was unknown
at the commencement of the year 1855, at least
to the British Government and all their official
advisers; but those I have here stated will, I trust,
Sir, remove all doubt on that subject from your
mind: the Ordnance Select Committee reported
that "guns so constructed could never be con-
sidered safe," and even after witnessing the
wonderful endurance of two guns, desired to see
further experiments.
They cannot pretend to
have known the value of the method before!
Nor can Lord Palmerston's Government, as that
statesman sanctioned Mr. Mallet's spending
Nor can any of those who
have sanctioned the manufacture of 3,000 or 4,000
guns within the last three years on the old plan.
This being the case, and I have spent upwards
of £1,500 in experiments and in urging the
Government to use my method, I have no hesita-
tion in asking you, Sir, now that it is adopted, to
cause to be paid to me a suitable royalty on each
un manufactured according to my patent either
in the Royal Arsenal at Woolwich, or by private

thousands to test it.*

I published, in the MECHANICS' MAGAZINE, my reasons for habering Mr. Mallet's mortars would fail, before they Were tried, He had underrated the strength required.

tal in one piece, sur-
rounded by one or more
cylindrical castings of

wrought iron or gun me
tal shrunk upon the in-
ternal cylinder," &c.

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tube somewhat
conical, the greatest di-
ameter being just in front
of the trunnions and
tapering both ways, and
to apply the outer casing
in the form of collars or
rings driven thereon; and
in some cases I apply two
or more layers of such
rings, according to the
strength sought to be ob-
tained, the trunnions be-
ing of one piece with one
of the rings. I also form
such outer casing of wire
or rod wound spirally in

one or more layers around
the inner cylinder or
tube," &c.

(Here other extracts from Captain Younghus. band's paper the Times, the Daily News, and other journals follow.)

Of these extracts I would wish, Sir, to draw

your especial attention to that from Captain
Younghusband's report," the parts are then in
that state of initial tension which is necessary;"
and to that from my own description,- by
forcing on the rings the necessary degree of tension
can be obtained;" because this tension is the
essential and novel feature; and the similarity of
expression is striking. If the necessity for this
tension was known before to any one, and cannon
were publicly constructed accordingly, my case is
not good (though even could that be proved I
fancy I have some claim on Government, having
spent a large sum of money to prove this neces-
sity to them, they denying it), as the words of Her
Majesty's patent to me declare it void "if the
said invention is not a new invention as to the
Public Use and Exercise thereof in our United
Kingdom of Great Britain and Ireland, the Chan-
nel Islands, and the Isle of Man." Sir W. Arm-
strong's own letter is, I presume, conclusive,
that his first cannon was made on my patented
plan; "the gun," he says, "is composed internally
of steel, and externally of wrought iron, applied
in a twisted or spiral form." I am informed that
now he makes the inside of wrought iron, think
ing thereby to evade the words of my patent,
while retaining the only essential feature of it,
viz: the tension on the outer part.

core:

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"It now only remains to be stated, that course of the long series of experiments made w this gun it has been fired nearly 1,300 times without sustaining any permanent injury either in the breechloading arrangement or otherwise. The only parts exposed to wear (and none are seriously so) are separable from the gun, and can with great facility be renewed."

On this point Captain Younghusband's evidence is still more decisive. After describing numerous experiments made at Shoeburyness with the gun, he tells us that

"Mr. Armstrong, believing the gun to be stronger than necessary, suggested its being returned to him to have it re-bored for a heavier projectile."

Why then did Mr. Armstrong in the later gans use wrought iron? Evidently to attempt to evade my patent. On the publication of his letter in the Times of January 3rd, 1857, I sent it and my

specification to a lawyer, and asked him if my
patent included the method described in the letter.
His reply was that it did, and that, without my
permission, Sir William could not continue to
manufacture his guns I wrote to inform Sir W.
Armstrong, and obtained a reply promising to
"negociate" with me before "using" the inven-
tion "commercially." This promise was written
on the 21st of January, 1857, yet on the 11th of
February, three weeks later only, Sir William
a provisional specification substituting
filed
wrought iron for the steel and cast iron mentioned
In November, 1856, I had the
in my patent!
pleasure of seeing Sir Wm. Armstrong at his
Engine Works, near Newcastle. On that occasion
he expressed views exactly coinciding with my
own, published nearly two years before, and dis-
tinctly told me that the principle of the construc-

tion of his cannon was to have the exterior in a
state of permanent strain, and that it mattered
little which of several suitable metals were used.

He then agreed to manufacture a gun for me on my plans in which the above-named principle was to be applied by forcing a small tube into a cast iron larger one, the latter forming nearly the entire gun. He afterwards declined making it.

I am advised by eminent lawyers that neither this nor any other unimportant alteration would enable him legally to use the essential feature of my patent. I was prepared to try the question this summer by an action against the Elswick Company, but was stopped by a declaration by General Peel that if I continued it, he would cease to consider the question of the infringement of my patent rights in Woolwich Arsenal, or at least to correspond with me on the subject.

In choosing whether I would submit my case to the decision of a legal tribunal, where any quibble might have deprived me of my rights, or to that, of an English statesman and gentleman, I could not hesitate. I made a discovery of great value to my country; I offered it to the country, and urged its acceptance; to enable me to raise money to prove its value, which after being denied for four years has now been acknowledged, and my plans adopted, not only as better than the old system, but as the only known method whereby sufficient strength can be obtained for rifle cannon of any size. This has been proved by the bursting of the 32-pounder and 63-pounder guns rifled by Mr. Whitworth, and by that gentleman imThis might mediately adopting my plan for those guns he is do for a private individual, but I feel certain now making. Her Majesty's Government, so long as you, Sir, are Secretary of State for War, will never sanction such an evasion. Even were it fair, or even legal, it would be most prejudicial to Her Majesty's

service to substitute an inferior metal for the
inside of the gun, merely to save the trifling

See MECHANICS' MAGAZINE for April 22, 1859, p. 24.

It remains for you, Sir, to decide what the country shall do for me; I can thank my God that He has enabled me to do my duty to it. I have the honour to, Sir, Your obedient servant,

A. T. BLAKELY, The Right Honourable The Secretary of State for War, &c., &c., &c.

THE NEW BRONZE COINAGE.

A CORRESPONDENT of the Times writes as follows:-A very sensible article, extracted from the MECHANICS' MAGAZINE, has been inserted in several of the daily papers on the above highly important subject, and I respectfully beg a small space in your columns, while I, as a practical engraver of some experience, endeavour to answer it. I shall feel too glad that if by your kind insertion of the opinion of one of the profession it should succeed in inciting others with more ability to supply my defects in striving to vindicate the national ability of the engravers, designers, and modellers of the present age. I will first glance at the highly commendable and honourable desire for improvement that has lately been shown in all our late national undertakings in connection with the fine arts, viz., by means of a public and general competition, judging the relative merits and capabilities alike of the highest and lowest engaged in the work required, and I ask you, Sir, the editor of the leading public journal, and the public generally, if it has not been of the greatest advantage to the country; therefore, why should not the same course be followed in the present instance? I have such perfect faith in the versatility of genius of our native artists that I have no hesitation whatever in saying they will relieve our Lady Emblem from the uncomfortable position she has occupied for so many years. The questions

raised are:

What impressions are to be given to the new bronze coins, and why not have something new? To this I answer there is indeed a vast field open

for improvement.

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[The above letter calls for but very few remarks from us, since it offers no contradiction whatever to our comments of last week. We can assent to CC TO THE EDITORS OF THE MECHANICS' MAGAZINE." all four of Mr. Busk's "facts," and still leave the GENTLEMEN,-In your Magazine of last Friday subject precisely as we then stated it. We regret, you were so kind as to give a drawing with a however, for Mr. Busk's sake, that he has not the candour to acknowledge plainly that our first estidescription of my elongated flat-faced iron or steel rifle bolt. I shall now be much obliged if mate of the book was fairly formed. Seeing eviyou will be so good as to insert a drawing of my dences of very recent composition in all the elongated pointed rifle shot. The four-grooved chapters, and finding them plentiful in many willow wood, with a sharp rifle cutter correwooden jacket is cut out of a piece of seasoned places, we concluded that the book was recently written, and every intelligent reader of it will do sponding with the bore of the rifle; a hole is the same. From this conviction, we are quite drilled out the centre of the jacket, which is then content to let Mr. Busk's explanations have whatever weight may belong to them, notwithstandplaced in the rifle mould, and the molten lead is poured through the hole, thus forming the bodying the difficulty we ourselves have in accepting of the shot and a leaden disk protecting the base some of them. Take this 4th "fact" of the above of the wooden jacket. In the year 1851, when letter, for example. Mr. Busk says he has never the Kaffir war was raging, and the letters of read either Mr. Isherwood's work or our quotamany officers from the scene of action stated that tions from it. How difficult it must be for us to British soldier, impenetrable jungle of thorny the Kaffirs sheltered themselves in the, to the believe this statement the reader will judge when mimosa, in the midst of stony and rocky ground, Mr. Isherwood, as quoted we put two passages side by side, thus:where our horizontal fire of musketry could make no impression on them, I wrote to the editor of the Naval and Military Gazette suggesting that my elongated rifle-shot and percussed shells fired

vertically might have the effect of driving the

The

howitzers, and carronades, but that in their fall
they made but a slight impression on boards
Carnot's round shot vertical experiments bore no
placed on the ground. Now, the nature of
analogy to my plan of firing vertically elongated
sembled the arrow shower, Carnot's that of a ball
rifle shot and percussion shells. My plan re-
falling from a sling. Every archer knows how
deeply an arrow falling vertically penetrates the
ground, and that it requires some force to draw
I am, yours obediently,

Again, is there so much poverty of inventive editor inserted my letter, but with an observation Kaffirs from their jungle strongholds. skill among engravers that there is danger of get-of his own, that Carnot made experiments by ting something worse than the present impres-firing vertically round bullets from mortars, I here assert that if the means of publicly and generally testing the question be allowed, there will be found plenty of native artists capable of making and executing a better design. To the last question, Is there no one in the kingdom who has talent enough to sketch out a design which would at once be symbolical of the ocean's sovereignty of Great Britain, and a fit impression for its coinage? I finally reply, let the opportunity be given of trying the fact, and proof would be shown that our countrymen have not degenerated, but will be found in numbers, ready, willing, and competent to execute a design that shall at once be a fit emblem to represent the coinage of the first country in the universe as it will the artistic skill of its people. Let me entreat, Sir, your powerful and generous advocacy in aid of the following proposition, should no better be

found:

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It is reported in Toulon that orders have been received from the French Admiralty to cease disarming the fleet, and that the forts commanding the entrance to the harbour are being armed with the guns which have hitherto been kept in store.

One of the Armstrong guns, an 80-pounder, forged at the Elswick factory, was recently tested in the long range at Shoeburyness, in the presence of the Ordnance Select Committee at Woolwich Arsenal, and gave the most wonderful results as regards accuracy, &c. The flight obtained was 9,000 yards, or upwards

of five miles.

it out.

Rosherville, 5th September.

J. NORTON.

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ble to keep them in order.
great that it was impossi-
During the hostilities at

and around Canton, the

English established a shop
on shore at Hongkong for
repairing; they also had,
at the same place, the
floating workshop, "Vol-
cano," sent out from Eng-
THE "NAVIES OF THE WORLD."
land, completely fitted up
TO THE EDITORS OF THE "MECHANICS' MAGAZINE." with tools and power for
GENTLEMEN, I have not the slightest wish to doing a large amount of
and
enter into any dispute, nor to prolong this cor- casting, forging,
respondence further than may be requisite for the finishing; and both these
statement of the following facts:-
establishments were kept
sations Lexicon," which you say
1. With regard to the articles in the "Conver-constantly employed on
the gun-boats, there be-
was not printed ing, out of about fifteen,
in the Times, nor heard of in England until usually a couple under-
January"-this article originally appeared, I be- going repair; in fact, the
lieve, last September, and had, as I observed, repairs upon them were
"made a great sensation throughout Europe" long enormous.
For economy
before it was discussed in England. The trans-
of fuel, durability and re-
lation of it given by me in the "Navies of the liability as war vessels for
World," together with the greater portion of the
critique thereon, was in type last November.

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2. The list of the French navy was in type
shortly after, as was also a large portion of the
rest of the book, though it was not published in
its present form till the 28th May.

3. The parliamentary papers you allude to I
did not see till March. The information extracted
from them, which is not furnished in the appendix,
together with the comments upon Sir John
Pakington's and the extracts from Sir Wm. Arm-
strong's speeches, together with various other
subjects, were embodied with the matter already in
type (and which had, of course, been "kept
standing") just before the volume went to press.
4. The work you name, Mr. Isherwood's
"Engineering Precedents for Steam Machinery,"
I do not remember ever to have heard of, nor did
I ever see the quotations therefrom in your Maga-
zine of the 18th February. There can, therefore,
be no extracts from that book, nor from your

constant use, the ma-
chinery of these gun-
boats cannot be recom-
mended, however well
adapted to the momentary
purpose for which they

were constructed."

Mr. Busk's "Navies of the World," p. 146.

"Well made, however, as the machinery of these gun-boats was, and by the best makers, both engines getting out of order, and boilers are constantly owing no doubt, in a great measure, to the excess Y velocity of the screw. The fifteen gun-boats employ ed in the late Chinese war constantly kept two large steam factories (one work in executing their afloat and one ashore) at repairs; therefore, until

some more durable ma

chinery can be devised, these vessels can hardly be considered available, except for temporary emer gencies in hostile operations upon an enemy's coast."

perience in literary matters to read the above exNow, we ask any man of the slightest ex tracts carefully, and then tell us if he finds it easy to believe that the writer of the second extract had never read the first, particularly when he remembers that Mr. Isherwood (as we said in February) "derived most of his information respecting our gun-boats from personal examination of those employed in the capture of Canton," he being in China at the time. But we do not wish to urge such objections further. Let those who have confidence in us do the best they can with Mr. Busk's statement; as for others, they may read the book for themselves, and then judge us harshly-if they can. EDS. M. M.]

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THOMAS'S HEAVY RIFLED CANNON FOR | miles,* lay any town on the coast in ashes, in a GUNBOATS.

If,

THE author of the interesting paper on "Experiments in Gunnery" given in this number, in the volume from which that is taken proposes the use of the powerful rifled gun represented in side and front view in the annexed engraving. He says our own heavy guns are constructed upon a principle so false that the only wonder is that so few accidents happen with them; those of the largest size are not only unsafe, but also very inferior in power to the American guns. however, it should be discovered that rifled guns of six or eight tons weight-the weight of some of the guns employed in the American service can be constructed of wrought iron, then, indeed, a powerful piece of ordnance will be obtained; a compound shell, of 2 cwt. and upwards, could be fired from it, and a greater range and accuracy combined would probably be attainable, than could be acquired with any other description of gun, such as could with convenience be used. A fortress or a floating battery, attacked with ordnance of this kind, could scarcely escape destruction. The length of the bore of the gun here illustrated is nine feet, and the calibre eight inches; the metal which surrounds the charge is nearly twelve inches in thickness; this (if the guns were constructed of the new puddled steel) would probably be sufficient to give it ample strength, and weight enough to prevent great recoil. A shell of 2 cwt., similar to that shown standing on end below the muzzle of the gun in the engraving, and a charge of from 25 lbs. to 30 lbs. of powder, might be used with it; a is the front view of the gun. "A long, low, strongly built vessel, possessing great steam power, armed with a gun of this kind, would prove," says Mr. Thomas, "infinitely more destructive than the steam battering-ram which has recently excited some attention. A vessel such as I have described would possess great advantage over a steam-ram, from the difficulty which would be experienced Family Cyclopædia, The, 3s. 6d. with the latter-first, in striking a vessel under Moore's History of the British Ferns, 3 edition, 7s. 6d. sail or steaming; and secondly, in getting disen-Needham's Physiology of Articulation, 3s. cl., ls. swd. gaged from it afterwards.

very short time, and with perfect impunity. This may be accomplished, and will be; if not by our own nation, by another. It is questionable, how ever, whether the 11 or 12 inch guns, such as form the armament of the American corvette, Niagara, would not prove more destructive in close action-from their large diameter and heavy bursting charges-than even the powerful rifled guns which I have described. Before adopting rifled guns into our naval service, to the entire exclusion of smooth-bored guns of large calibre, much consideration would be necessary, and many experiments required to be made. I see no reason, however, against the acquisition of such a gun as I have described. The only difficulties which lie in the way of it have already been once

surmounted in the case of Messrs. Horsfall's

13-inch gun, and will, no doubt, be still more completely overcome. The great tensile strength which is required for guns to throw compound shells arises from the absence of windage, and also from the friction on the whole surface of the bore, which impedes the progress of the shell along the bore, and allows the fluid produced by the fired charge to accumulate behind the shell, and thus to exert a great strain on the gun. Nearly the maximum results as to range and general effect-regarding the means employedmight be attained with the gun represented in Plate 7. Any larger piece of ordnance would not only be unmanageable, but probably unsafe; and although a larger gun could, of course, throw a heavier projectile, still a comparatively greater effect could not be obtained with it, as the range of the larger shell would probably not be greater, unless a higher velocity could be given to it; so that, to acquire the same relative effect, comparatively greater means would have to be employed.

LIST OF NEW BOOKS.

Our Farm of Four Acres, 7 edition, 2s. Parkinson's Under Government, Key to Civil Service, 3s. 6d.

10s. 6d.

"Ten or twelve vessels of the above descriptionsea-going gun-boats-each armed with a heavy Shot-Gun and Sporting Rifle, The, by Stonehenge, rifled gun to throw shells of 2 cwt., and with steam power sufficient to give them a speed of at least fourteen knots, would, at a distance of three

At this range such a gun would not require an elevation of more than about 11°.

ON EXPERIMENTS IN GUNNERY. By LYNALL THOMAS Esq., F.R.S.L. GUNNERY furnishes no exception to the rule, that there must be a cause for every effect; indeed, in scarcely any investigation is a knowledge of causes more essential than in conducting experiments in gunnery. Hence, when we find that two shots, fired apparently under precisely the same circumstances, show a variation in their range, or in their accuracy, we know that a cause must exist why this should be the case; and although the fact of the variation in the effect of shot fired under similar circumstances shows that general rules only are applicable in gunnery, and that no single result is to be relied on, yet a proper study of cause and effect in this matter will considerably

reduce the chances of failure.*

It is not sufficient merely to obtain a greater range, accuracy, or general effect; but we should know, also, how these results are obtained, if we wish to profit by them in the greatest possible degree.

Before any new principle can be successfully applied in practice, repeated failures must always be expected. I may go so far as to assert that they are absolutely necessary to the complete attainment of success. Because the Lancaster, Whitworth, and other guns may have failed in fulfilling the expectations that were formed respecting them, their trial is, by no means on this account, to be considered as an entirely useless expenditure of either time or money. On the contrary, it was necessary that they should be made, and, no doubt, considerable advantage in many respects will arise from their having been made.

When men possessing mechanical skill in the highest degree-as Mr. Whitworth, for instanceundertake experiments with a view to any improvement in the construction of implements, whether of a warlike or a peaceful character, good must always result; for, even if they fail in establishing their views, considerable light will always. be thrown upon the subject to serve as a guide for the future. Still, although the aid of able mechanicians is of great importance in the

These somewhat trite remarks were called forth by an observation which was made to the author by an artillery officer of some eminence-to the effect that "the firing of the charge with cannon was attended with such varying results, that it was useless to think of applying any rule for regulating the thickness, or strength of metal, required for guns of different calibres ""

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