§44. 



THE CIVIL ENGINEER AND ARCHITECT'S JOURNAL. 



291 



was granted. It is obvious tliat tlie application of this principle must depend 

 upon the particular circumstances which are brought to hear upon each par- 

 ticular case. The existence of a single copy of the work, though printed, if 

 brought from a depository where it has long been kept in a state of obscurity, 

 would afibrd a very different inference from the production of an Kncyclo- 

 paidia, or other work in general circulation. The question will be, wliether, 

 upon the whole evidence, there has been such a publication as to make tlie 

 description a part of the public stock of information ? We think, therefore, 

 as this question has not been submitted to the jury, there ought to be a new 

 trial in this case. 



COAL-BREAKING MACHINES. 

 Among the many improvements which have lately taken place in the 

 business operations of this region, there is none more striking than the 

 saving of expense in breaking and screening coal. A few years since every 

 ton of coal which washrokenfor shipment cost from 30c. to 37^c. to reduce it 

 to proper sizes, while now the expense wilJ not much exceed one-fifth of this 

 amount. This truly surprising result, it- many others of a similar kind is 

 the effect of niachineiy, and has been brought about by successive experi- 

 meuts and improvements. The attempt to break coal by machinery, we be- 

 lieve, was first made by Mr. Sabbaton, and afterwards by Mr. Later, but not 

 proving as successful as was anticipated, they were afterwards abandoned. 

 Improvements were then made upon the old system of breaking with the ham- 

 mer, and instead of breaking in the pile, cast-iron plates, with holes sutli- 

 ciently large to allow coal of proper size to pass through were used. This 

 was found to diminish the expense considerably, making the cost of breaking 

 about 20c. or 25c. per ton. A further improvement was then made by 

 turning the screens by steam instead of hand, which caused a still further 

 reduction in the expense of preparing the coal for market, the cost being 

 from 12c. to 18c. per ton. But satisfactory as these results were, and greatly 

 reduced as the expenses have been by these improvements, Mr. Battin, of 

 Philadelphia, has improved upon them, and invented a coal-breaking ma- 

 chine, which will, in all probability, supersede every other invention of the 

 kind, and eventually enrich its ingenious inventor. One of these machines 

 was first erected at Mr. Bast's mines, for the purpose of breaking white ash 

 coal, and found to answer every purpose intended; but, at the same time, 

 fears were expressed that it could not be used to advantage in breaking the 

 red ash. Subsequent events have shown that these fears were groundless, 

 and a machine is now in operation at Milnes and Spencer's mines, by which 

 the red ash is broken with no greater loss than on the cast-iron platform. 

 Encouraged by these successful experiments, other machines are now in the 

 course of erection at the collieries of Andrew B. White, and also at the 

 Delaware Coal Co.'s works, the latter of which will, probably, go into ope- 

 ration during the present week, and the former the ensuing week. These 

 machines, to work advantageously, require engines of about 20-horse power, 

 and will break the coal at an expense of from 8c. to 10c. per ton, according 

 to location, including 3c. per ton, which is paid the patentee. Another ma- 

 chine for the same purpose, but constructed upon an entirely different prin- 

 ciple, we learn has been put in operation by the Beaver Meadow Coal Com- 

 pany. This machine consists of a square box, in which are several iron bars 

 placed longitudinally at such distances apart as will make the coal of proper 

 size, while a roller is so situated as to pass over and force the coal through 

 the openings. The invention is favourably spoken of, and will no doubt 

 answer a good purpose in breaking the white ash, although we learn the 

 waste is much greater than that caused by Mr. Battin'a machine. — Miners* 

 Join^ial (of America). 



CAPTAIN WAHNER»S EXPLOSIVE POWER. 



It has long been known to the public that Captain Warner was In poasesslon of an ex- 

 plosive power with which he had alreiidy experimented upon privately, — Negociations 

 have been goinR on with Government for some time, but witliout coming to any auctjess- 

 fill issue, it was therefore determined by the friend* of Captain Warner, to try the experi- 

 ment without the aid of tJovernment, tor this purpose Mr. Soamcs the eminent ship 

 owner, liberally ofl'eretl a vessel for the occasioa, and some private friendi of the Captain 

 raised the sum requisite for the attendant expenses. — The vessel selected was the "John 

 o'Gaunt," a barque of iUO tons burtlien, three masted, full bowed, strongly built and sea- 

 worthy, she was given up to tlie Captain eaily in the present month, and towed round to 

 Brighton, where tlie experiment was to take place. 



The vessel was talcen in tow by the *' Sir William Wallace" steamer, on board of whiuh 

 was Captain Warner, accompanied by another steamer, "The Tees," aiid was brought 

 round shortly befure six o'clock in the afternoon to the position slie was appointed io 

 occupy, al)out a mile and a cpiarter from the Brighton shore, opposite tlie Old Ship Hotel 

 and the B.iitery. It was previously arranged that from the signal-staff of the battery on 

 the west cliff, a flag w.ts to be hoisted, by the command ot Lord Ingeslre and Captains 

 Dickenson and Henderson, to indicate to Captain Warner when the ship, the subject of 

 his operations, was to be destroyed. The reason of this arrangt^ment was to remove any 

 doubt ns to the bona fide nature ot Captain Warner's power of destroying a pursuing ves- 

 sel, without having any communication with that vessel at the moment of her destruction. 



As soon as the "John u'tiaunt" had been towed to her position, (he moat intense 

 anxiety prevailed among the spectators on shore, and every movement of those ou board 

 the tug-boat was wutdied with the greatest interest. Captain Warner was himself on 

 board the tug, and it had been previously arranged that when the signal was given from 

 the battery the crew of that vessel should go below, leaving no other persons on deck but 

 the captain and the niate. This arrangement was observed ; and immediately afterwards, 

 the steamer, which had hitherto been towing the ship by a hawser, put back, and came 

 abreast of her— a position which she maintained for a very few momeuts, and then a^in 

 proceeded to her former situation, about a quarter of a mile eastward of the John n* Gaunt. 



Captain Warner now hoisted a Union Jack at the mast-head of the steamer, denoting 

 that he was ready to operate, and only awaited the hoisting of the Union Jack from the 

 tiagstart OD the battery, to be replied to by Captain Warner hauling down his signal. This 

 had been flying some time before it was answered from the battery; and then arose 

 another delay, in consefpience of some adventurous persons in a small cutter, in spite of 

 the presence of th« Tees, and of two armed revenue cutters besides, to ke«p off intrudem, 

 going close alongside the ship. Captain Warner hauled the Union Jack half-way down 

 only until the cutter and its nccupants were out of danger. The Union Jack was then 

 hauled down entirely. The grand crisis had now arrived ; and we may say, without ex- 

 aggeration, that the suspense of all present was painful; the silence was deep and un- 

 broken. AtsiK o'clock, precisely, the devoted vessel appeared to be struck niidshii)3, at 

 which point shot up a huge column of water, intermingleil with the shingle of her ballast, 

 which was mistaken by most persons for a cloud of >nioke. Then a low booming and 

 gurgling noise, indicating a submarine explosion, but not approaching a loud report. 

 "The vessel is struck !" was uttered by a thousand voices, and the next thing tu be seen 

 was the falling of the mainmast and the mizeu mast. In less than a minute, the vessel 

 was riven almost from stem to stern, and in less than two minutes and a half the vessel 

 literally tumbled to pieces as if by magic. Her mizen went by the board, her mainmast, 

 a new one, was shot clean out of ber ; she heeled over to port to an angle of ^/j degrees, 

 and her main hatchway being open, daylight was visible through her bottom timbers ou 

 her starboard side, and probably her larboard also, having been blown away, and she 

 seemed to part asunder as she went down, in about 86 feet water, leaving nothing per- 

 ceptible but the top of her foremast. The time which passed from her being struck and 

 her sinking could not have exceeded 2i minutes. Some few of the more enthnsiastic 

 spectators, chiefly professional men, raised a cheer, but with the iiiaHs all was mute as. 

 tonishment. The eyes were rivetted on the last observable fragment of the large object 

 that but the mouient before floated gallant on the waters " like a thing of life." A work 

 of destruction so sudden, so frightful, so stupendous, appeared impossii)le for a moment 

 even to the thousands and tens of thousands that witnessed it. It was like an awful mystery. 

 There were none of the ordinary circumstances which accompany similar catastrophes. 

 There was no smoke, there was no fire, there was no noise, save the low groan of the 

 rending timbers, and the succeeding hush of the waters as they rolled over the instan- 

 taneous wreck, and then arose a melancholy feeling, for it was impossible to prevent the 

 imagination depicting the terrific effects of such an explosion upon a peopled ship, thus 

 silently and suddenly perishing. The success of the experiment is admitted to have l>een 

 perfect and entire : and the wonderfully destructive power of its agency is universally ad- 

 mired. Tlie • modus operandi' Is kept secret; and, so long as this is the case, it will be 

 impossible to say how far, under all circumstances, It would prove efficacious against an 

 enemy's fleet, or saf* for our own fleet to carry. 



The following certificate has been issued : — 



July 21. 



We, the undersigned, hereby certify that the operations against the John o'Gaunt, of 

 300 tons, conducted by Captain Warner, off Brighton, on Saturday the 20th instant, were 

 under our management and control. We further certify that the explosion did not take 

 place from any combustible matter either on board or alongside the ship, but was caused 

 by Captain Warner, who was on board tlie William Wallace steamer, having the ship in 

 tow at a distance of aI>out 3<K.i yards, and that the explosion took place in consequence of 

 a signal made by us from the aliorc, the time ot which was not previously known by Cap- 

 tain Warner. 



We further declare our belief that Captain Warner has never been on board the ship 

 since she left Gravesend.— Ingestre, Captain, R.N., C.B.; T. Dickenson, Captain, R.N. ; 

 W. H. Henderson, Captain, R.N., C.B.— Abridged from tlie Times. 



It is stated that Captain J. Norton has invented a most formidable percussion shell, to 

 explode at the bottom of the sea. An iron tube, like the barrel of a musket, is screwed 

 into a shell of any size, water-ti^rht. A rod of iron, about ^ lb. weight, and one foot in 

 length, is suspended within the tube, by means of a split quill passing througii a hole in 

 the upper end of the rod, the other end being armed witli a percussion caj). The mouth 

 of the tube is closed with a screw lid, almost water-tight. Tin or brass wings being at- 

 tached to the upper end of the tube, will keep it in a vertical position during its descent 

 to the bottom of tha aea ; and the shock, on its striking the bottom, will cause the bar of 

 iron within the tube to fall and produce the percussion and explosion. Should it be found 

 difticiilt to make the shell water-proof, Captain Norton|ia satisfied that percussion powder, 

 made from silver, will explode by friction or percussion, even when "mixed with water." 

 These shells have been also adapted to field artillery, and have been pronounced " simple, 

 safe, and efficacious." 



The properties of explosive compounds are interesting at this moment, in their assumed 

 connexion with Captain Warner's secret. Two of the most formidable compounds known 

 are said to be the chloride of nitrogen, or azote ; and its brother compound the iodide of 

 ammonium, or nitrogen. The mechanical force of the chloride of azote in detonation, is 

 superior to that of any other known, not even excepting the ammoniaeal fulminating sil- 

 ver. Dulong was the first to investigate the iodide of ammonium, and exchanged for his 

 knowledge in one experiment three fiiigeri, and iu a succeeding experiment, an eye. 



"THE CITY OF LONDON" IRON STEAM-SHIP. 



This magnificent Iron steamer lias just been constructed In the Clyde, by Mr. Robert 

 Napier, at the expense of 40,000/., for the Aberdeen and London Steam Navigation Com- 

 pany, for steaming regularly between Aberdeen and the metropolis. She has just made 

 her first voyage from Aberdeen to Wapping. in an unusually short space of time ; though 

 the wind was adverse, and she had ou board, besides passengers and a cargo of goods, 210 

 head of cattle, and 700 boxea of salmon. Ou ber return from the Thames to Aberdeen, 

 she accomplished the passage in 38 hours. 



The City of London is of a-Jrairable symmetry, and nice proportion of length, breadth, 

 and height ; which detract ftom her apparent magnitude. She is, however, a stupendous 

 vessel, and commodiously planned ; her large dimensions giving scope for every acconi^ 

 modation. Her actual measurement is as follows :— 



Feet. In. 



Length between perpendiculars .. .. 215 



Length over all .. •• -• •• 231 



Breadth of beam between paddle-boxes .. .. 31 



Extreme breadth across paddle-boxes .. .. 52 C 



Depth of hold .. .. •• -. 20 



Her tw« engines together are rated at 4H0-horse power, and her registered tonnage is 



7;J2 tons— her measurement, lllOtons. The poop stands 4 feet above the main deck, 



and is 115 feet long, and nearly 40 feet broad. The cabins are spacious and comfortable, 



and the ornaments are much more chaste tliau usual. In a pleasure trip, this supeib 



vessel, it is reported, accomplished the voyage from Greenock to Aberdeen, a distance of 



540 miles, in 42 hours, or at the rate of about 13 miles an hour. Captain Cai-gill, by whom 



she is commanded, speaks highly of the ease with which she may be managed. With tlie 



exception of the Great Britain, which has not yet been to sea, she is Uie largest iron steam 



ship afloat. 



Marine Glue. — The naval cdrrespmvlciit ot the Tinu-s at Sbeeniess says 

 that the Speedwell, tender to the Blazer, is in dock having her bottom cleaned and cop- 

 perod, the marine glue with which she was sized about four months since having proved 

 a failure as a substitute for copper lu keeping clean and free from animal and vegetable 

 escregcences the bottoms of th« vessels to which it has beau applied. 



