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stood and its value estimated, an approximate | courses. 3. That when iron ships have heeled | Dr. Scoresby's observations in the Royal Charcurve of deviations cannot be projected, from over for a considerable time upon northerly ter (which were extensively published soon after four observations, with any chance of success. courses, they have been found to windward of his return), he (Professor Airy) recommended Two cases have been named in which it ex- their dead-reckoning. To these may be added, to the Admiralty that such a mounting should ceeded a point; on board the Royal Charter it the existence of an impression among compass be tried in the Trident, and in a recent number amounted to six and seven degrees. In such adjusters and others who have paid attention of the Athenæum he communicates the facts of instances it might give rise to an uncertainty to the subject (among the latter may be named the case. Among the places which are left at in the deviation of twice this amount. the managing owner of the Cunard Company, liberty by the rigging of the ship, the best (in a While the deviations arising from permanent Mr. Charles M'Iver, a gentleman of great ex-magnetic sense) was, he says, selected; and magnetism and vertical induction vary as the perience in iron ships), that iron deck beams great care was taken to mount the compass in sine of the angle of direction of ship's force, at are a chief cause of compass disturbances. an unexceptionable manner. It was, however, the station of the compass, with the magnetic The following may also be quoted from a totally useless. Its deviations were meridian as indicated by the disturbed needle, number of other cases :--Captain Bonfellow of large that it could give little assistance in the quadrantal deviation has been shown to the steam-ship Laconia states, that the same interpreting the indications of the compass vary as the sine of twice the azimuth of ship's course which, with an even beam, would make below; and when compared with a corrected head by disturbed compass very nearly. In the Smalls from the coast of Spain, with wind compass, and above all with a corrected adjuspractice these two deviations are combined in at N.W., would make the Tusker to windward, table compass, it was of no use whatever. The every conceivable manner. With the excep- and on the opposite side of the Irish Channel. Astronomer Royal further remarks that the tion of one or two cases of elevated compasses, The captain of the Sarah Sands states, that his deviations of the mast-compass of the Great the whole of the deviation tables which have compensated steering compass has acted re- Eastern are large; that that of the Royal been obtained in Liverpool by the Committee markably well, except when his vessel has Charter became useless from sluggishness, prohave exhibited plus quadrantal attraction. heeled to some extent. This compass is placed duced, he conceives, by the injury done to the Perhaps a minus deviation of this kind would over, and comparatively near, large masses of pivots and bearings by the tremor of the mast; be found to exist in a compass placed within a vertical iron. Captain Leitch, of the City of and that he does not think the method will skylight, in which the iron deck beams are cut Baltimore steam-ship, has favoured the Com- ever be extensively used. off on each side of it, or in an iron ship with mittee with observations made during several wooden beams. voyages. In every instance the north end of the needle has been attracted to the high, or weather side of the ship. This is the most extreme case which has been recorded. From slight list to starboard to slight list to port, the standard compass, placed about five feet above the deck-house, has been observed to change eight degrees. The apparent cause is the iron beams of the deck house. There seems reason to suppose that when the deck beams are divided to make space for a skylight, a position for a compass may be found in which the errors from heeling might naturally compensate each other. The errors from vertical induction of deck beams would certainly vary with change in geographical position, or with the earth's vertical intensity. Thus, in the City of Baltimore, Captain Leitch mentions variations in the deviation of three-quarters of a point while his ship was in the Mediterranean; but in the North Atlantic, as he approached America, he has noticed an extreme instance of more than a point and a half. The Committee are anxious to collect all the information possible on this intricate and important section of the compass inquiry, as it is felt how very imperfect must be any deductions which may be made from the evidence which has to this time been placed before them.

:

Following the remarks of the Committee we next come to the following practical topics: 1. Errors induced by heeling in iron ships. 2. Elevated or mast and standard compasses. 3. Modes of swinging ship. 4. Modes of adjusting compasses. 5. Projection of deviation tables by curves. 6. Miscellaneous operations of the Committee.

The errors arising from the heeling of iron ships are among the most perplexing which demand a captain's attention. As a number of causes may conspire to produce, modify, or cancel their effect, it is not surprising that the evidence before the Committee on this branch of the investigation was not very complete. Among such causes may be named the followinga. The rising or lowering of the attracting mass, causing its magnetism to act with more or less leverage as it approaches to or recedes from the plane of the compass card. b. Vertical iron or magnets below and near the compass. c. Induced vertical polarity in iron deck beams, increasing as they incline from their usual horizontal position. d. Proximity of badly proportioned and badly placed chainboxes. e. Action of horizontal compensating magnets when they are placed below and too near the compass card. The last, though partially corrective of some errors from heeling, in certain positions of the ship, appear to aggravate them in others.

Great variety of opinion prevails as to the utility of mast compasses. Though in some ships they have been discontinued after a trial, The three first-named causes are described as their use is becoming very general, although tending to attract the north end of the needle they certainly are not always free from a conto the weather side of the ship in north mag-siderable amount of error. In moderate netic latitude, and to leeward in the south magnetic hemisphere, and as increasing or decreasing the usual deviations, according to their name and the direction of the ship's head. These three may act in the same direction and in the same ship. It is difficult to estimate their separate effects, but the last is supposed to be most prejudicial. The great expense attendant on heeling and swinging ship in port, and the delay caused by such an experiment where every hour is valuable, have prevented the Committee from directly testing this. Deductions can only be made, therefore, from the evidence afforded by various captains and an inspection of the arrangement of the iron near the compasses of their respective ships. Evidence from a number of captains shows:1. That in a large proportion of iron ships the compasses are affected by heeling. 2. That errors from heeling are generally most complained of when ships are on or near four-point

weather and large ships, mast compasses are
stated to act well; but in small ships, where
the motion is greater, the oscillation pre-
vents their being of service, except in fine
weather. In nearly every case they show an
attraction to ship's head in north magnetic
latitudes (giving east deviation with ship's head
east, and west deviation with ship's head west,
taking ships to the south of their course), and
very little quadrantal deviation. The usual
plus quadrantal deviation is found to decrease
as the compass is carried aloft, and is believed,
in some cases, to change to minus quadrantal
after a certain elevation is attained. The effect
of the transverse iron, and iron placed before
and aft the compass, appears to be cancelled,
and in some cases exceeded, by the action of
the ship, as a long bar placed below the com-
pass. The Astronomer Royal has, however,
exceedingly little faith in the use of compasses
at the mast head. Relying on the result of

We now come to the question of the best modes of swinging ships. Undoubtedly, the easiest and best mode of ascertaining the deviations of a compass is by reference to the bearings by it of a distant object, whose true magnetic direction is known; but, in a river or a confined dock, such distant object is seldom attainable. Next to this, the Committee approve of the system of fixed magnetic bearings of a conspicuous object, which has been adopted at Liverpool. The principle is the same as that of reciprocal bearings, with the two advantages of freedom from error in the shore compass, and saving the time usually lost in repeating and deciphering the shore signals. There is another mode sometimes adopted in Liverpool and at other places that of carrying the shore compass round the dock, so as always to be in a line with the ship's masts, and by preconcerted signals checking the ship as she approaches the true points of the compass. This plan does not admit of accuracy, even when pains are taken to insure it. To an adjuster who understands his business it must be tedious, while in the confined situations, in which only it can be employed, the shore compass is liable to varying disturbances, which give rise to most inconsistent tables of deviations. In some cases it has occasioned serious

errors.

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DURING the period embraced in the account of Cort's invention, and its introduction already given, everything had gone on with greater success than had attended any inventor. The merits of the invention were not only placed beyond a question, but the merit of the inventor was universally acknowledged. The mill at Fontley was in full operation, and visited by the large manufacturers anxious to be informed as to the best means of practising the new manufacture. Licences were taken at royalties estimated to yield £250,000 to the owners of the patents.

At this crisis, 1788, Adam Jellicoe, the partner of Cort, committed suicide, under, it would appear, the pressure of dread of exposure of being a defaulter to the amount of £27,500 of public money entrusted to him, and for which

he was responsible, for wages of seamen and officers of the navy.

The following letter, found in the iron chest of Adam Jellicoe by G. Black, an accountant employed by Mr. Trotter, the Paymaster, to schedule Jellicoe's effects preparatory to the extent, in 1789, dated 11th November, 1782, throws some light on the causes of the act :"Ever since I have had public money in my hands, it has been a constant rule with me to have the value of it in Navy bills in the iron chest, that in case of my death the balance might be immediately paid in; and I have always had much more than my balance by me, till my engagement about two years ago with Mr. Cort, which by degrees has so reduced me, and employed so much more of iny money than I expected, that I have been obliged to turn most of my Navy bills into cash, and, at the same time, to my great concern, am very deficient in my balance. This gives me great uneasiness, nor shall I live or die in peace till

the whole is restored.

"I have considerably more than £20,000 engaged in the business with Mr. Cort and my son, and have paid almost all my engagements and acceptances. I expect the returns in bills for ironmongery wares will now come in very fast; besides which, General Tenyn owes Mr. Cort nearly £3,000, which Mr. Wilkinson, in Abchurch-lane, assures me is as safe as if I had it. Mr. Morgan, the Purser (whose name is in the contract for iron wares), owes Mr. Cort near £3,500. Both these debts are assigned to Messrs. A. and S. Weston, 31 Fenchurch-street, for my use. Messrs. Weston have also in their hands monies received from Captain Wm. Hay and Captain O'Hara, in the Royal Navy, due to Mr. Cort and assigned to me.

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paid by the deponent as Paymaster of His Majesty's Navy unto Adam Jellicoe, late of Highbury-place, in the county of Middlesex, Esq., the chief clerk in the pay branch of the office of the Treasurer of His Majesty's Navy, for the purposes of his paying and applying the same in discharge of the wages of the officers and seamen of His Majesty's Navy, but which and apply for the purpose for which this deposaid sum the said Adam Jellicoe did not pay nent paid him the same, but which said sun he the said Adam Jellicoe at different times lent and advanced unto the said Henry Cort, from and owing; and this deponent saith he verily whom the same now remains justly due believes that the said Henry Cort is much decayed in his credit and in very embarrassed circumstances, and therefore this deponent verily believes that the aforesaid debt so due and owing unto His Majesty is in great danger of being lost if some more speedy means be not taken for the recovery than by the ordinary

process of this Court.

(Signed) "ALEX. TROTTER."

DECEMBER 2, 1859.

only £13,895 had been placed by Mr. Trotter to the credit of the alleged default. "Everything available having thus been turned into money and paid in diminution of the debt," the mendacious memorial continues: "the patents granted to Mr. Cort were also secured, and for a long time hopes were entertained that Parliament would, by rewarding so beneficial an inlessening the debt," (.e. the balance of the vention, have provided a further fund for £27,500 and upwards sworn to by Mr. Trotter); "but that, notwithstanding the great merit of the invention-and the use of it to the country ever been made." If it be fair to interpret remains uncontested-no compensation has men's words by their actions, there can be little difficulty in reading what was in the minds of Mr. Dundas and Mr. Trotter, when they ruined Mr. Cort. At the date when he was turned out of his own works and other freeholds in Hampshire, and his partner, Jellicoe the younger, snugly installed in them, the Treasurer of the Navy had no greater difficulty before him in the way of obtaining payment secured" to Mr. Richard Crawshay and others, balance of it, than to carry the contracts" he had either of the sworn debt of £27,500, or of the and demand of them a payment of 10s. per under their hand and seal, to the holders ton of puddled and rolled iron, secured

of those contracts.

The Treasurer had

the legal power to exact dues amounting between 1789 and 1798 to nearly £200,000. What he did receive could not be ascerand he refused any personal information to the tained from the ashes of burnt documents, Commissioners in 1803, and to a Committee of the Commons in 1805; but, according to the memorial quoted, he had received nothing, for the balance of A. Jellicoe's default remaining unpaid in May, 1800, is stated in that document to be £24,846, which, subtracted from the sworn debt, leaves £2,654 and upwards public by the illegal seizure of the inventor's effects, and the peculiar surrender to his private as the total realised in eleven years to the partner of the freeholds seized under a Crown writ for the discharge of a public debt. When of demanding of the contracting iron-masters we consider how very simple was the proces the patent dues, which for the year 17-9, at the date of the extent, amounted to £15,00), 1791, and which demand might have been enforced by the same legal process used to ruin £15,000 more in 1790, and £25,000 more in the inventor, it is not difficult to surmise the motive for abstaining.

"But should my death be sudden, and before I can make up the public balance, I hope I shall not be reflected on, as I have always remarkable. The then Treasurer (Mr. Dundas) The action taken on this affidavit was most meaned honestly and justly; and I must adopted a liability for which he was in no earnestly entreat the Treasurer, Paymaster, or way honourably or otherwise liable, as more whoever is most concerned, not to be severe in than £20,000 of the sworn debt had been abrequiring the balance to be immediately re-stracted eight years previously, during the trust stored, lest my character should be traduced, of Mr. Wellbore Ellis. Between 1781, when and my son Samuel (who I hope is in a way to Mr. Ellis left office, and 1789, there had been make a comfortable provision for his brothers and four surrenders of trust in the office of Treasisters) and my family be ruined. ble, that all these four persons could successurer; as it was incredible, not to say impossisively have overlooked Jellicoe's current default, so well known in the office, there must have been some strong consideration moving Mr. Dundas and Mr. Trotter to have induced them to incur the risk of perjury in order to assume unnecessarily a debt to the Crown of £27,500 and upwards. In the previous year, 1788, Mr. Dundas had called upon A. Jellicoe to restore his defalcation, and make good his balance, to which intimation Jellicoe replied, July 10th, 1788: "But (in the meantime) in case you should think a security necessary for the responsibility of the situation which I have the honour to hold, I beg leave to offer the enclosed (bonds and assignments of Mr. Cort's patents) amounting to a larger sum than I can at any time hope to have in my hands unemployed. (Signed) A. Jellicoe." That Mr. Dundas thought very highly of the value of these securities at this time is shown by his memorial to the Treasury, May 1800, in which, referring to Adam Jellicoe's connection with "Mr. Cort, the patentee of an invention for making wrought from unwrought iron," he proceeds: "The sanguine hopes that were entertained of Mr. Cort's inventions becoming productive, and the inefficiency of harsher measures being considered, it was determined Mr. Jellicoe should not be immediately suspended, but that he should be pressed to use Such is a brief outline of the facts connected every exertion to pay up his balance." with the lamentable suicide of Cort's partner, then gives an account, wholly false, of the ex-made the subject of further investigation in and the conduct of the authorities, which was tent subsequently issued, immediately after A. 1805 on the question of the impeachment of Jellicoe's death, for he states that "all his Lord Melville. effects were turned into money and paid in diminution of the debt," whereas it was disthat Mr. Cort's freeholds in Hampshire had not covered by the Commissioners of Naval Inquiry been sold, but that Samuel Jellicoe, the son of them, under the extent, and had continued the defaulter, had been put into possession of peaceably to enjoy them without any process of the Crown up to the date of that report in 1803, a period of fourteen years; and the Commissioners likewise ascertained that out of the effects of Adam Jellicoe, scheduled by George Black, under the extent, at £89,657, a sum of

Mr. Sykes' agent, in Crutched Friars, has a Navy bill of mine, value £2,800, with interest due on it, on which I borrowed £2,000 of him. Mr. Weston above-mentioned will, in case of my sudden death, assist in raising money for me, as I doubt not Messrs. Bennett and Cure, Fenchurch-street, to save me from any imputation, and my family from being hurt; and they may be sure of being repaid by remittances from Mr. Cort and my son, so that I hope my balance will shortly be made up; and as I have ever meaned to deal justly and honestly with the public and every private person, I again entreat that some favour may be shown to the family of one who has served faithfully for above forty years, and that it will not be insisted upon that the balance be immediately paid up.

(Signed) "A. JELLICOE. "P.S.-I have also a mortgage of £4,000 on the estate of Mrs. Catherine Dent, and above £800 interest due on it."

The following affidavit in the Exchequer of Mr. Trotter, shows the liability thrown on Cort by the proceedings of his partner :—

“Alexander Trotter, of the Navy Pay Office, Esquire, and Paymaster of His Majesty's Navy, maketh oath and saith, that Henry Cort, of Gosport, in the county of Southampton, iron manufacturer, is justly and truly indebted unto His Majesty in the sum of £27,500 and upwards, for so much of His Majesty's money |

He

Mr. Whitbread with

great, but surely not undue severity, charged of which was acceded to without examination) Lord Melville, upon this memorial (the prayer Treasury for this £24,846, " under false p with obtaining a receipt or discharge from the

tences."

Her Majesty's ship Wrangler returned to Woolthe 40 lb. and 80 lb. Armstrong guns at sea. wich yesterday from an experimental cruise to try Wiseman, Vice-President of the Royal Ordnance most complete course of experiments was carried Select Committee of Woolwich Arsenal, and Lieut. ont under the inspection of Capt. Sir William Themas L. Ward, of the gunnery-ship Excellent. Sixty rounds of ammunition with the elongated shot were fired with perfect success, and every equipment pertaining to the gun was pronounced faultless.-Times of Saturday last.

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We observe now what we did not notice when the first part of the work was recently before us, viz., that this new edition is to be published in monthly parts. In a twelvemonth's time, therefore, the re-issue will be completed. This is a most satisfactory arrangement.

This part shows that the great improvements noticed in the first were not put forward as mere beguilements to purchasers. The labour and expense bestowed upon the new edition are as manifest here as they were in it, the 384th page of the present part carrying us only to the article Borax, which appeared on the 234th page of the edition of '53. We have new articles on Artillery (94 pages), the Atomic Theory (3 p.), Borwood (1 p.), Bells (1 p.), Benzole (14 p.), Boghead coal (2 p.), the commencement of an elaborate one on Boring, and some scores of shorter ones. At the same time many of the old articles are extendedthat on Barley from 10 lines to 11 pages, on Bis muth from 2 to 8 pages, on Bleaching from 17 to 33 pages, on the Blowpipe from 6 lines to 3 pages, on Boracic Acid from to 2 pages, on

Borax from 2 to 3, and so forth. The article on

Bleaching deserves particular notice, as it contains a large mass of new and valuable matter, and is illustrated by a truly beautiful display of engravings on wood. We recommend readers-all who can afford five shillings a month for the purpose -to put themselves in possession of the parts of this edition of Dr. Ure's unexampled work without delay.

Stories of Inventors and Discoverers in Science and the Useful Arts. A book for Old and Young. By JOHN TIMES, F.S.A., Author of "Curiosities of

London," "Things not Generally Known," &c. With Illustrations. London: Kent and Co. (late Bogue), Fleet-street. 1859. MR. TIMBS has here contrived to put forward 350 pages on inventors and discoverers without once acknowledging (so far as we can observe) that he is at all indebted to the MECHANICS' MAGAZINE for any of his facts or statements. This will seem a curious circumstance to those who know how prominent a place this Magazine has held for thirty-six years past in connection with inventions and discoveries in "science and the useful arts;" and we may, without vanity, say that he might have avoided some errors had he given greater heed to what has been published here. But having intimated this we hasten to express our sense of the great value of the volume before ns. It is, indeed, "a book for old and young," and such a book as no other compiler known to us could be expected to produce. Mr. Timbs does not bestow his labour grudgingly upon these volumes of his which are appearing every few months. They are well thought over, and worked at energetically. This volume is one which no man in England, be he ever so cultivated, need be ashamed to peruse, or could peruse without deriving much instruction from it.

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The Gardeners' Year Book, Almanack, and Directory, 1860. By ROBERT HOGG. London: Cottage Gardener Office, 162 Fleet-street, E.C.

MR. HOGG who is a Vice-President of the British Pomological Society, author of "British Pomology," "The Vegetable Kingdom and its Products," and co-editor of the Cottage Gardener— has here started an exceedingly useful and cheap annual. The number for 1860 contains 150 pages of well-selected matter, and is so admirably edited that the success of the author's undertaking will be assured by it.

Cassell's Illustrated Almanack for 1800. London: Cassell, Petter, and Galpin, La Belle Sauvage

On the Comparative value of Certain Sults for rendering Fabrics Non-inflammable. By FRED. VERSMANN, F.C.S., and ALPHONS OPPENHEIM, Ph. D., A.C.S. London: Trübner and Co., 60 Paternosterrow. 1859.

THIS pamphlet forms the substance of a paper read before the British Association at the Aberdeen meeting in September last. An article, which, we recently published on uninflammable fabrics (which was copied into most English news papers, and translated into several foreign journals), and a letter from the authors which appeared in our Weekly Gossip" a week or two since, render further description of the painphlet un

66

necessary.

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Our Military Engineers; being an Inquiry into the
Present State of Efficiency of the Corps of Royal
Engineers. London: Judd and Glass, 38A Now
Bridge-street, and Gray's-Inn-road.
THE conclusion at which the author of this
anonymous pamphlet arrives, after giving the
matter the fullest attention, is that the separation
of the Civil and Military duties of the officers of
the corps of Royal Engineers is unavoidable, if
we wish to preserve the corps. They cannot exist
as they are at present. They may contrive to
bungle over their civil duties with the assistance
of the civilians attached to the department, but
having no one to perform the military duty for
them, their utter worthlessness as a professional
corps will be fully exposed. How they contrived
to hush up their deficiencies in the Crimea cannot
be imagined, unless it is attributed to the unity
which prevails among them; for there is no body
of men who adhere so well to each other in con-
cealing their deficiencies from the authorities and
the public as the officers of the corps of Royal

Engineers."

Proceedings of Societies.

MANCHESTER LITERARY AND PHILOSOPHICAL

SOCIETY.

Ordinary Meeting, Nov. 15th, 1859. Mr. J. C. Dyer, Vice-President. in the Chair. Mr. John Atkinson made a communication respecting a curiously-shaped fossil, found about a month ago in the Upper New Red Sandstone in a quarry near Runcorn. This fossil had been described in the Athenæum of the 29th of October last by Mr. Henry Wilson, Surgeon, Runcorn, who pointed out its striking resemblance to the mullion and tracery of part of an ancient gothic window, not merely in size and general outline, but in the moulding upon it, as if of tooling by the hand of some primitive mason. On the 5th instant the

Athenaeum contained two letters on the same sub

ject. Neither of the writers had seen the fossil. opinions being divided, Mr. Atkinson visited the Runcorn Hill Quarry, examined the fossil itself, and found it to be a mass of fine-grained sandstone veins. These had been deposited in thin horizontal lamina and moulded in a system of cracks formed by desiccation and subsequent modificationprobably by the action of water-in the bed of marl (hiere eight inches thick) so celebrated as being that on which the last of the Labyrinthodon order of animals have left their footprints in such vast abundance at Stourton, Runcorn, Lymm, and various other localities. Professor Roscoe communicated a paper by W. S. Jevons, Esq., late Assayer in the Sydney Branch of the Royal Mint, entitled, "Observations on the Gold Districts of Australia." At the close of the paper the author considers the important question of the probable future yield of gold to be expected from Australia. He believes that no more very large or rich fields Having in view the difficulty which might be supposed to arise in the separation of the civil that the present "gold-drift" has by no means of alluvial gold will be discovered in Victoria, but and military duties of the corps of Royal Engi- been worked out; so that when capital and more be got over by confining the corps to the practice bear upon the ground which the first gold-digger neers, the author believes that all difficalties may complete mechanical appliances are brought to of military duties-which would include the con- has relinquished as worthless, a constant and remustruction of works of fortification, the practice of nerative supply of gold can be relied on. It is military bridges, pontooning, siege operations, otherwise, the author believes, with the true gold light infantry manoeuvres, &c.. being under the mines, those in which the auriferous quartz reef is control of the Commander-in-Chief. The exclu- worked. Here the supply is, as far as we know, sively civil duties which they are now supposed to unlimited-the assertion that quartz reefs became perform, and consisting of the designing, exepoorer in gold as they decend being as yet quite uncuting, and repairing barrack buildings, store- proved, so that when the due combination of houses, the management of War Office lands, science and capital has been brought to bear upon &c., should be handed over to a civil corps analothe subject, there seems to be no reason why the gous to the Military Store Department, and sub- auriferous quartz reef should not be followed as jeet to the Secretary-at-War. This corps would far as any other metal-bearing vein, as in the be available in time of war as a substitute for the Cornish tin mines or in the silver mines of Mexico late Army Works Corps, and could be made to and Peru. Hence the author concludes that the perform the professional duties required in con- supply of gold from Australia will probably connection with Quarter-Master-General's Depart-tinue to be large and regular. ment, thereby permitting the employment of the Mathematical and Physical Section, Nov. 10th, corps of Royal Engineers solely in the military 1859. Mr. T. Heelis read a paper "On Storms, operations of a siege. The Civil Corps is to be with some attempt to ascertain their tracks in the composed of men who, previous to their appoint-neighbourhood of the British Islands, and their ment, have received a practical training in archi- analogy to other Cosmical Phenomena." tecture, civil engineering, building, &c.

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Toulon at half-past 11 on the morning of the 24th The steel-plated frigate Gloire was launched at inst., in presence of an immense concourse of spectators. A vast multitude, anxious to see the launch, occupied every point from which the dockyard of the Mourmillion is visible. The harbour presented a most animated appearance. Thousands of boats THIS almanack abounds in exceedingly well-formed a line to hail the Gloire on her passage to selected matter, is lavishly illustrated, and is the sea, which she accomplished with perfect anexampled for cheapness. success.-Times.

Yard.

MEETINGS FOR THE ENSUING WEEK. MON.-London Inst., "On the radiation and absorption of heat," by Professor J. Tyndall, F.R.S., at 7 p.. TUES.-Nat. Civil Engineers, Continued discussion on Mr. Grantham's paper "On Arterial Drainage and Outfalls." At half-past nine the visitors will adjourn to the library, when candidates will be WED.-Royal Inst., "On the Physical History, Structure, and Materials of the Earth," by E. W. Brayley, Esq., F.R.S., at 7 p.m.

balloted for.

Society of Arts, "On the forces used in Agriculture," by Mr. J. C. Morton, at 8 p.m. THU.-Royal Society, I. "On the Analytical Theory of the Attraction of Solids bounded by the surfaces of a class including the Ellipsoid," by Prof. Donkin; II. Supplement to a paper on the Thermodynamic Theory or Steam Engines with dry saturated steam, and its application to practise," by Prof. Rankine; III., " On the effects produced in Human Blood by Sherry Wine," by Dr. Addison; IV. Supplement to a paper on the influence of White Light of the different coloured rays, and of darkness on the development, growth, and nutrition of animals," by Mr. II. Dobell, at 8. 30 p.m.

FRID.-London Inst., "On certain principles of vegetable and animal chemistry," by F. A. Malone, Esq., F.C.S., at 7 p.m.

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All No. 3 hot blast iron.
scrap.

The actual breaking weight being 58 tons, it | the dodecahedron with rhomboidal faces is left, as
would appear that the constant co-efficient assumed composed with 4 rhomboidal cubes. The solid
is in each instance too high for the quality of iron content of the dodecahedron is equal to two cubes,
of which these beams were cast. This result whose side is equal to the shortest of the diagonal
appears to have been anticipated by Professor lines of the rhomboidal face.
Hodgkinson in the case of large beams; and in
ene of his experiments, art. 147, on a beam cast
625 as the co-efficient, which agrees with the re-
for Messrs. Marshall and Co., of Leeds, he gives
sult of this experiment.

Applying this co-efficient to Professor Hodgkin-
son's formulæ, they will be as follows:-
2.05 a d
First formula, W=

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The first of these would give 58-2 tons, and the The beams were cast on their sides, and were a second 58 31 tons, as the breaking weight; either very good sample of workmanship.

The section of each beam was of the form recommended by Professor Hodgkinson, and upon which his formula were based; the total depth of the beam in the centre was 244 inches, and at the ends 20 inches; the bottom flange was 15 inches wide, and 24 inches thick; the vertical part of the beam was 14 inch thick; and the top flange was 4 inches wide, and 1 inch thick; the total length of the beam was 34 feet 6 inches, and the distance between the supports was 30 feet 9 inches; the weight of the beam was 3 tons 8 cwt. 1 qr. One of the beams was tested up to the breaking weight with the following results :With a load in the centre of

Tons. Cwt. 31

Inch. 8 the deflection was 87.

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50 8

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2.00.

2.25.

2.56.

2.70.

58 0 the beam broke, the ends springing back from each other 2 feet 3 inches, the fracture indicating a good sound casting.

There was no permanent set observable in any of the experiments, until the breaking weight was applied, the beam being allowed to recover itself

on the removal of the load in each case.

of which calculations would be sufficiently correct
for any practical purpose.

ON THE ANGLE OF DOCK GATES AND

THE ROOF OF THE BEE'S CELL.

rance Society.

By CHARLES M. WILLICH, Actuary University Life Assu-
THE proper angle at which dock gates should be
placed, so that the timber employed should yield
the most favourable result, has often been discussed
by mathematicians, and determined as a problem
The angle has been

of maxima and minima.
found to be 109° 28′ 16′′

A patient investigation of the properties of the
cube has enabled me to succeed in dividing it into
several geometrical solids, with which many defi-
nite and regular geometrical bodies may be con-
structed. The dodecahedron with 12 rhomboidal
faces is composed of 2 cubes, 6 octohedrons, or 4
The obtuse angle on
oblique rhomboidal cubes.
its face measures 109° 28′ 16′′, being the same as
that adopted by mathematicians for the angle of
dock gates; and by Maclauren in the beginning of
the last century as the best for the angle of the
roof of the bee's cell. It will be readily seen by
the models submitted with this paper, that by
elongating the dodecahedron, it becomes the pre-
cise form of the bee's cell, with angles measuring
109° 28′ 16′′.

Each of the remaining beams was tested with a
load of 20 tons in the centre, the deflection vary-cube in two different ways.
ing from ths to ths of an inch.

The calculations for the strength were based on the following formulæ, given by Professor Hodg kinson in his "Experimental Researches on the Strength and Properties of Cast Iron:"

[blocks in formation]

No. 2. The rhomboidal dodecahedron as composed with six octohedrons.

N.B. The cubic octohedron with which the dodecahedron is composed, is not the regular platonic body with eight faces, which are equilateral triangles, and which may be ob tained by a partition of the tetrahedron ; but this cubic octohedron has each face with two angles of 54° 44′ 08′′, and one of 70° 31′ 44′′, being, in fact, one-half the rhombus on the face of the dodecahedron. This octohedron is composed of two of the six pyramids into which a cube may be divided, as seen by the model.

No. 3. Cube marked with lines to show its partition into six bodies.

No. 4. Cube built up with the six bodies. No. 5. Two of No. 4. united to form one-third of a cube.

No. 6. One of these bodies of which No. 4 cube

is composed, being one-sixth of a cube divided into two, A and B, each being one-half a pyramid

or one-twelfth of a cube.

No. 7. A rhomboidal cube, composed of six halfPyramids. Seven of these rhomboidal cubes form the bee's cell (see No. 1), and four form the dodecahedron.

No. 8. Pyramid, being one-sixth of a cube or one-half of the cubic octohedron.

No. 9. Pyramid, divided into four bodies.

N.B. No. 8 and 9 together form the cubic octohedron.

No. 10. One-quarter of a pyramid divided and re-united so as to form one-third of a cube, which

is

one-eighth of the solidity of the cube from which the pyramid was derived.

N.B. This body is of the same form as No. 5;
but only one-eighth of the solidity. No. 10
may also be produced at once by dividing the
pyramid into four of these bodies, by quar
tering across instead of diagonally; so that
the one-eighth part of the pyramid unites
either way to form the quarter of the pyra
mid, cut diagonally or across.
No. 11. To show that by the union of the half-
pyramids a prism may be formed.

I have succeeded in dividing or parting the
1st. By lines from
the centre to the 8 solid angles of the cube, which
will give 6 four-sided pyramids. 2nd. By lines
from one of the upper angles of the cube, drawn
diagonally to the 3 opposite angles, dividing the
cube into 3 equal and uniform solids. Each of THE INVENTION OF THE
these solids being halved forms a left and a right-
handed solid. These 6 solids, though equal in
solidity, differ so far in shape, as 3 are left-handed
and 3 right-handed, in the same way as the hands
of the human body.

Each of the six bodies obtained by the second
mode of partition may be divided into two of
equal solidity and of similar shape. Two of these
bodies, each being one-twelfth of the cube, may be
so united as to produce the pyramid obtained by
the first mode of partition. Six of these bodies,
each being one-twelfth part of a cube, may be so
arranged as to form the oblique rhomboidal cube.
one-sixth of the cube obtained by the first mode
It may also be observed that the pyramid, or
of partition, may be divided into four bodies, each
of which is one-third of a cube containing one-
eighth of the mass of the cube from which it was
derived. So that, in fact, we may go on dividing
and reproducing bodies of a similar shape, and
still retaining the diagonal lines of the cube. How
how much farther than our powers of vision go,
far this subdivision may be carried in nature, or
I will not at present venture an opinion. We can
imagine the commencing atoms may be infinitely

small, when we remember the wonders revealed
by the microscope.

List of Models accompanying Mr. Willich's paper.
No. 1. Model of bee's cell, composed of seven rhom-
boidal cubes. By taking away 3 of these cubes,

Read before the British Association at Aberdeen,
September 20, 1859.

HOT-BLAST

USED IN IRON-MAKING.*

THE following history of the invention of the hot-blast used in iron-making was recently presented to the Institution of Mechanical Engi neers in a speech by Mr. Neilson, the inventor of the hot-blast system :

Six or seven years before he brought out the

plan, he had read a paper before the Glasgow Philosophical Society on the best mode of taking out the moisture from the atmospheric air in summer time, previous to its entrance into the furnace through the tuyeres; for it was found that the make of iron was much impaired in summer weather both in quality and quantity, and he had become satisfied that the cause lay in the greater proportion of moisture contained in the air at that season. His first idea was to pass cined lime, so as to dry it thoroughly on its way the air through two long tunnels containing calto the blast cylinder of the blowing engine; but Ewing, of the Muirkirk Iron Works, in regard to this plan was not put to trial. About that time his advice was asked by a friend, Mr. James

mile from the blowing engine, which did not obtain a sufficient supply of blast at that distance, and consequently did not make so much iron as two similar furnaces situated close by the same engine; and it then occurred to him that since air increases in volume according to its tempera

a blast furnace situated at a distance of half-a

The publication of this article has been unavoidably delayed for several weeks.

ture, if it were passed through a red-hot vessel in this respect the case had much similarity to fronting the sea, lately granted by the Town before entering the distant furnace, its volume that of his countryman James Watt, who, in con- Council for the purpose, a building fitted with would be increased, and it might be enabled to nection with the steam engine, invented the plan baths and all other necessary appliances, to which do more duty in the distant furnace. Being at of condensing the steam in a separate vessel, and shipwrecked mariners can be brought at any hour that time engaged in the Glasgow gas works he was successful in maintaining his invention by not of the day or night, and at which there will be made an experiment at once on the effect pro-limiting it to any particular construction of con- the certainty of finding all things necessary to reduced upon the illuminating power of gas by a denser. He was glad of this opportunity of store them to health and strength; and it is supply of heated air brought up by a tube close acknowledging how firmly the English iron-firmly believed that by such means many a valu-. to the gas burner; and found that by this means masters stood by him in the attempts made in the able life (as has already been the case in three inthe combustion of the gas was rendered more per- early time of the use of hot blast to deprive him stances) may be saved. At a public meeting lately fect and intense, so that the illuminating power of of the benefits of his invention; and to them he held in the town hall, it was determined to appeal the particles of carbon in the gas was greatly was indebted for the successful issue of the severe to the humanity and generosity of the public augmented. He then tried a similar experiment contest he had then to go through. generally to assist the inhabitants of Great Yar with a common smith's fire, by blowing the fire mouth in establishing an institution which may with heated air; the effect was that the fire was be considered as partaking of a national character. rendered most brilliant, with an intense degree of heat, while another fire blown with cold air showed only the brightness ordinarily seen with a high heat. Having obtained such marked results in these small experiments it then occurred to him that a similar increase in intensity of com

bustion and temperature produced would attend the application of the same plan on a large scale to the blast furnace; but his great difficulty in further developing the idea was that he was only a gas maker, and could not persuade ironmasters to allow him to make the necessary experiments with blast furnaces at work. At that time there was great need of improvement in the working of blast furnaces, for many furnaces were at a stand for want of blast, being unable to maintain the necessary heat for smelting the iron; and unless as much as £6 per ton could be obtained for the iron noprofit was realised, on account of the heavy expenses attending the furnaces. A strong prejudice was felt against any meddling with the furnace, and a kind of superstitious dread of any change prevailed, from the great ignorance of furnace managers with respect to the real action going on in the furnace, and the causes of the fluctuations that occurred; when a furnace was making No. 1 iron no one would be allowed to touch it, for fear that if any change took place it might be many weeks before the furnace got round again from white iron. He at length succeeded, however, in inducing Mr. Charles MacIntosh of Glasgow and Mr. Colin Dunlop of the Clyde Iron Works to allow him an opportunity of trying the application of heated air for blowing a furnace; and though the temperature of the air was raised but little, not more than about 50° Fahrenheit, he was glad to be allowed to make a trial even with so small an amount of heat. This first imperfect trial of hot blast, however, with a rise of temperature of only 50°, showed a marked difference in the scoria from the furnace, causing it to be less black, or containing less iron; and he was therefore anxious to try the plan on a more extensive scale, in order to satisfy himself as to the change in the make of iron, and to establish the correctness of the principle. He was still retarded by the strong objections of ironmasters to any alterations in connexion with the furnaces, which prevented him from making the necessary experiments for ascertaining the best way of carrying out the plan: in one instance where he had so far succeeded as to be allowed to heat the blast main, he asked permission to introduce deflecting plates in the main, or to put a bend in the pipe, so as to bring the blast more closely against the heated sides of the pipe, and also increase the area of heating surface, in order to raise the temperature to a higher point; but this was refused, and it was said that if even a bend were put in the pipe the furnace would stop working. These prejudices proved a serious difficulty, and it was two or three years before he was allowed to put a bend in the blast main; but after many years of perseverance at the subject he was at length enabled to work out the plan into a definite shape at the Clyde Iron Works, as had been so completely and correctly described in the paper that had been read. The invention of the hot blast consisted solely in the principle of heating the blast between the engine and the furnace, and was not associated with any particular construction of the intermediate heating apparatus; this was the cause of the success that had attended the invention, and

HELP FOR SEAMEN.

include

IT being pretty generally known that we very many naval gentlemen and persons more or less connected with the navy among our readers, we are not unfrequently brought in contact with nautical affairs. Among other objects of interest

the sailors' home and refuge for shipwrecked mariners, at Great Yarmouth, has lately come under our notice, and we think it not altogether beyond our duty to say a word in its favour.

In no part of the world are there so many shipwrecks as on the east coast of England. During the year there were no fewer than 600 casualties between Dungeness and the Pentland Firth; being more than 50 per cent. upon the whole number on the entire coast of the United Kingdom. This very large proportion is attributable to the vast number of ships passing and repassing along these shores. It is calculated that not less than 40.000 sail, exclusive of vessels engaged in our fisheries, annually pass and repass through Yarmouth Roads; most of them being engaged in carrying the produce of our collieries to London and other markets. This Roadstead is the only natural harbour of refuge on the eastern coast, and it is not uncommon to see many hundreds of vessels there at the same time; whilst on some occasions a long continuance of adverse winds, either way, will cause a much larger number to remain at anchor.

But Yarmouth Roads are surrounded by a a natural breakwater of very dangerous sands, which in foggy weather, or when heavy gales sweep the coast, occasion many fearful shipwrecks. During the last three years more than 500 vessels were stranded, wrecked, or lost off this coast, or compelled to put into Yarmouth harbour with damage. As a necessary consequence the loss of life is also great; and the number of shipwrecked mariners who are landed at Yarmouth, year after year, is very considerable. The benefits which "The Shipwrecked Fishermen and Mariners' Benevolent Society" has rendered at Yarmouth have long been gratefully acknowledged, but it has also been felt that something more was required. The survivors of a wreck or the crew of a foundered vessel, are brought on shore always wet and weary, frequently exhausted by cold and hunger-often more dead than alive. There was no place to which they could be carried but the public-house, where it was impossible to obtain, on the instant, those appliances which were so necessary to restore suspended animation, and such other remedies as circumstances required. To obviate this evil an Institution was founded at Yarmouth about twelve months since having for its object the social and moral improvement of the fishermen, beachmen, and seafaring population of the town; and combining the advantages of a sailors' home (so far as they are required here) and especially providing a place of refuge for the shipwrecked and destitute mariners of all nations. 288 shipwrecked and distressed mariners have already been received and relieved. Of this number 204 were British seamen and 84 foreigners of all nations.

The inadequacy of the present establishment has, however, been made most painfully apparent during the recent gales which have desolated our coast. In twelve days only, 109 shipwrecked mariners were brought to the Home, and relieved so far as the present limited resources would permit. In order, therefore, to meet the very urgent demands now made upon the committee it has been proposed to erect upon a most eligible site,

The Mayor of Yarmouth, who has brought this subject to our notice, has generously offered to receive donations; and we doubt not many readers of ours will gladly aid a cause which, at the present time especially, deserves the good wishes of our countrymen. We hope we need not apologise for devoting a few lines to such an object.

IMPROVEMENT IN THE VOLTAIC
PILE.

Ir is well known that Bunsen's pile, which is but a modification of Grove's, consists of a glazed vessel, containing a cylindrical element of zinc, which surrounds a porous vessel filled with strong nitric acid, into which a charcoal cylinder has been introduced, the liquid in the outermost vessel consisting of water acidulated with about 10 parts of sulphuric acid. Now, although this is a most powerful combination, and in general use, it has two great inconveniences: first, the quantity of nitrous vapour it evolves is highly unpleasant, and may become dangerous; and, secondly, the current produced is not of constant intensity. M. Thomas has just communicated to the Academy of Sciences a modification which he has effected

in this kind of pile, and which would seem to be quite free from the inconvenience alluded to. M. Thomas, in fact, shows that the development of nitrous vapour is one of the chief causes which interfere with the constancy of the current, inasmuch as they attack the copper ribands forming the electrodes, and effect certain chemical combinations, which give rise to counter-currents, and thus impair the principal one. He therefore causes these gases, as they are evolved, to pass into a porous vessel, where they are decomposed. In this process a secondary current is produced which, by the peculiar construction of the apparatus, is turned to account, and tends to correct the inequalities of the principal current. This arrangement also prevents the pile from becoming dirty, as is the case with Bunsen's pile.

COMPOSITIONS FOR COATING IRON SHIP'S BOTTOMS.-The following paragraph has been communicated to the morning papers: -“A number of gentlemen interested in shipbuilding assembled recently in the Southampton Docks, to witness the result of an experiment which had excited some interest among persons of that class. In the early part of last May the Royal Mail Company's steamship Atrato was coated on the starboard side with M'Innes's green copper soap, and on the port side with Peacock and Buchan's pink composition, for the purpose of practically testing the relative merits of the two articles in keeping the botton of the ship clean. On docking the Atrato for examination it was found that the starboard side was covered with coral pipe, shells, and barnacles, with a good deal of corrosion; while the port side was perfectly free from coraline incrustation or barnacles, having merely a thin slimy unctuous coating upon it. The result is considered as having incontestably proved that preparations of copper are of little value in preventing incrustation or fouling on the bottoms of iron ships, while their galvanic action must. sooner or later, prove injurious to the rivets and plates. The green composition is now being scraped off the Atrato."

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