The New York Herald Newspaper, September 20, 1876, Page 5

THE GREAT MIN. Precautions Taken to Guard Against All Accidents. RENDING THE ROCK. How the Columns and the Roof Rock Will Be Destroyed. FLOODING THE MINE. The Operation Performed bv Means of a Siphon. THE BATTERY BOMBPROOF. Boxing the Wires Leading Through the Headings. OF OPINIONS ENGINEERS. How the Astorians Regard the Approaching Big Blast. ULE SEES the destruction of every part of Hallett’s Pcint reef above the lovel of twenty-eight feet soundings by the tinfultanvous explosion of several thousand holes filled with beavy charges of nitro-glycerino and dynamite is an undertaking that necessitates the utmost precaution to guard against accidents and failure, With regard to the provisions against the former they must be con- sidered in two classes, local and general, and as such they will be explaimed in thd present article. The first care of tho engivecrs is to protect the exploding apparatus from injury by any parts of the rock what may be projected from the reef by tho force of the explosion. This they have accomplished in ihe manner hereinafter described. In a large mass of atratified rock such as that of Hallett’s Point reef, which bas been excavated with tunnols and transverse galler- les, the effects produced by equal charges of explosives i all the holes will differ very much in character. It mast be romembered that the resistance offered by a mass of rock to the force of the explovion is meus- ured by the shortest distance from tho contre of tne shurge to the free surface and by the cohesiveness of the atoms of which the rock is formed. Tho frst is termed the line of least resistance, or that along which the energy of the expanding gas gonerated by the combustion of the explosive finds the loast ob- Macle to its force, It a hollow sphere of tron, a shell, lor instance, with eceontric interior and exterior cir- ‘umferences, is charged with powder and fred, the ‘vacture will take Dlaco whore the shell 18 thinnest, and \ bowl shaped portion will remain unbroken, In liko manner, {ia cubical block of stone is perforated ob- Uquely to the plano of its sides, so as to leave a greater mass of the stone on ono side of the holo ‘ban the other, the weaker portion will bo thattored to pleces by the explosion of the wharge, while the heavier and stronger part will be only cracked intopieces. Now, if the density of the gneiss rock at Hallett’s Point was oqual through- but the entire mass it would be the casicst thing pos- wble for experienced mining engineers to calculate snd, indeod, to regulate, the effects that would bo pro- luced by the explosion, ‘They could graduate their sharges both as to strength and regulate thom as to lo- cation in oxuct accordance with the necessities of the case, and feol contident in tho results being as they desired to produco them. But with a forma- tion variable in its nature, and this varia on being complicated by _ stratification, and farther by the peculiar directions of the galleries and headings with relation to the lino of stratification, the difficalty of detormming positive results increasos a hundred fold. The axis of the reef in this instance {s coincident with its stratification—that is, it projects into the channel in the same direction as the allun- ment of the layers of rock, and, consequently, somo of the headings have been driven at right angles with this line, and across the stratification. While, therefore, tho explosion will split some of the supporting columns imto regular blgcks of the same thickness of the several strata, the effort of the force in others will be to tear the rock across what might bo called its grain. To mako this a Itlo cloarer, let us supposo two blocks of wood cut from the same piece, and with the same character of fibre. Now, one of these is simply split by the action of a wedge with comparatively little effort, while if we try to toar tho other end from ond tho resistance will be immense, In the same way the explosives will operate at Hallott’s Point reef on tho rock columns Vbat support the rool. To overcome the differ- ence inthe resistanco of the rock the engincers have made careful calculations by whieh they determined the requirements for each column sopa- rately. Perfect diagrams of the mass were made, giv- ing ite variations of outline at several heights trom tbe ground line to where it connects with the roof, The Mtratitication was indicated on these, together with the peculiar dogree of cohesiveness in tho particles of cach stratum, so that im reality the Graduation of the charge 1s made to depend on local conditions, each set of cartridges having « specified amount of work to perform on a given mass of rock. If the utmost foresight, therelore, cau so- curo tho best results, so far as the destruction of the columus is concerned, the operations at Hallett’s Point protnise to be eminently successiul. With rogard to the root rock or the untouched thell of the reef, all the varying conditions Gescribod in the’ columns exist in it with the additional complication of 1 like “shape which makes it almost self sus Could the columns be removed from under th y ‘sell the probabiiity 1s that it would not fail to sustain its own weight.and that of the supersueumbent water, In desling, therefore, with the roof, General wisely limited bis prospective results to a goneral frac- ture of tho svell with moderaie charges introduced @t considerabio intervals. These charges being fired simultaneously with those that shatter and rend the rock columus beneath are intended to assist im break- ing up the root, while it subsides on the débris of the columns, Thero is no intention whatever to blow the roof off the columns and scatter it in sinall pieces all around. it is hore that will be found the value of this plun as local procaution Against accident. «In order that any portion of the shattered columps should bo thrown by the force of tho explosion to u great distance it should firs! be vlown througa a covering of ten foat thick of rock which immediately overlies it with 8 force that could not be imparted by @ monster rified gun, Even though an opening iarge enough to per- Git the passage through of such a rock projectile fe would be met above the rock by an inrush- ing column of water m feet deep, which would so retard its motion as to cause it to rise but a few feet above the river surface. In ordinary blasting Operations, such as those commonly witnessed in the work of strect grading and sower cutting up town, it ls usual to cover the loaded hole betore tring with a number of logs chained together, $0 a8 vo prevent the stone from scattering with the shock of the explosion. Now, tho roof rock at Haliett’s Point acts in the very sane Way on tho heavily loaded columas, and will pro- wa any danger from arising when theo latter aro being tea. FLOODING THR WORKINGS, The introduction of water into every part of the belore firing must also be regarded asa local ution of two-fold value, In the first pluce tt the great mine in the most per- it with w powerful rearstant to pO Of ihe gaves beture they have accompished thoir work. In the absenco of tamping the line of least tesistange would be aluny the axis of the blast hote teolt und, therciore, instead of bursting turough the sur- rounding rock, the jorce of tbe explosion would pass off Unrough the bole us it does through the barrel of agun, In aw loaded rifte, for instance, tho bullet acis as 4 partial Lamping dor the charge, iuclosing it 60 As to concentrate the energy of the explokion. But as the resistance offered by the built ery much lest aun that ollered by the barrel itself, tho iine of leass ferisiance 18 in the direction of the vallet and along the barrel, If the builet was uyhtly wedged in the gun, wo that the exprosion could not dislodge it quickly, the guu Would burst iike the rock when te charge is exploded. Bus it will be asked, and Very uatarally, bow water will ofler as much ro- Mstunce in the depths of the Hallett'’s Pont min she rock that surrodads the cartridge. Wat imclosed iu & circumseribed place and chance of moving, becomes xs inert sure increuse: buat at the f the explosion, qquare fool of su it that depth woutd pressed on with a weight equal to ubout 1,250 pounda, ora Little more than fifteen pounds per aquare inch, \ ‘NEW YORK HERALD; ‘WEDNESDAY, SEPTEMBER 20, 1876.~TRIPLE. SHEET. the rapidity of combustion poeul: the capleaes used. Water resiits a sudden applica- tion of preasure but ytelds easily toa slow one. This is very simply illustrated by dropping a stone intoa pond trom a great hoight and repeating the operation close to the suriace, stone ts thrown off the sop of High Bridge into the Harlem River ¢ strikes water offering the stone. ‘The stone then sinks to the bottom with a comparatively slow deseent. Now, take anothef stone and hold it only one foot above the suriace of the water. Drop it, and 1¢ will enter the water without causing any covsiderable disturbapee, and will reach the bottom in the samo time as did the stone dropped trom the great powerful resistance to the passage of beight. It shows, theref blow is suddenly administe resistance will be in proportion to the ene: shock, and in this way it is possible to show t! Jorms 4 greater obstacle to the expansion of the gases from the exploding cartridges than the rock itself that surrounds them, tho resistance of the latter being un- variable, while that of the former is augmented, as explained abo With tho cavernous chambers then filled with water it will be impossible for the cbarges to fail in destroying the rock columns completely, provided the former are properly located und of the necessary strength. Regarding the flooding ot the workings as a measure of precaution ugainst the projection of pieces of rock itean be reauily seen that it will prove effectual, It has been stated by some engme that be- masses of rock were thrown ward from depths of water by the force explosions that there Nevessarily danger to be apprehended at Hallets's Point, but the circomstances that surround this unique work difler wholly from those attendant on ordinary submarine blasting. It been shown that the roof rock acts as # guard ugainst the flying upward of pieces from the columus; it bas also been shown that water resists pressure. in proportion 16 the force of that pressure. It may be also stated that a dody moving through water, either slowly or rapidly, tends to follow the line of least resistance, which would be a lino perpendicular to the surface, Therefore a mass of rock flying irom the ceatre of expiosion § sbould fret overcome the resistance of the water, which would tend 10 decrease its motion; second, it would be stopped by the descending weight of the roof rock; and, third, even if neither of these influences acted decidedly on its movement, its course should of neces- sity be upward in-a perpendicular line, and ite full naiurally in the exactly opposite direction, No one ever saw a piece of stone blown out of deep water ina direction at less than a mght angle with its surface, therefore all fear of flying lumps ot rock reaching New York, Astoria or Ward’s Island might be dismissed as absurd, When all the other preparations aro completed the operation of filling the workings will be accomplished by means of a siphon which ig urranged to pass through the colfer dam and admit the water with an easily rogulated flow. We present # diagram of the syphon and its mode of operation with the present article, When ready to be used and tho tide at the full height the injet valve will be opened on the top of the syphon, on which the water will at once flow in and expel the air from the entire iongth of the tube, As the tide falls below the level of the top of the tube the flow will cease to depend on gravitation, and will assume tho charac- tor peculiar to siphenic action. The water will be drawn up into the tube by the difference of pressure of the atmosphere on the surface at the short end from onthe longend, This can be ex. ry difference betwoen the weights of the Jong and the short columns of water, the operation of the syyhon being dependenton isturbance of the equilibrium of prossure, When the excavation is filled to the river level the ¢offor dam will be partially re- moved, so as to admit of airee flow of water im and Out, according as the tide rises and falla, ‘THK BOMS PROOF SHELTKR FOR THK BATTERIES. As av extraordinary precaution against accidents General Newton bas caused to be built a stout bomb proot building tor sheltering the batteries during tho that when & powerful to a water surface, the of the it water explosion, ‘Tho structure, of which a sketch is givea herewith, is a solid framework of avy timbers braced and supported iu the most substantial manner and sleoted ovor with pine boards firmly spiked to the framing, Over all this is built a cover- ing of dry masonry many feos thick und strong enough to resist the assauits of artillery, Within the building aro placed the two largo batteries and otbor apparatus that are required for the explosion. Although this precaution was adopted it is certain that no injury would have reached the batteries or their connections, THM GENKRAL KYFRCT OF THR EXPLOSION. Although much alarm exists respecting the offect of the explosion of so much nitro-glycerine and dynamite within a contracted space, it 1s wholly groundicss when tested by the conditions which are believed to be its exciting cause. The roek columns, which will really reciove the largest share of the explosives, can only transmit a downward shock to their bases, bocause they are wholly isolated trom eactrother by the sur- rounding water, and the roof rock through which a abock might be transmitted tothe permancat portion of tho rect will be seporated trom it at tho same moment that the columns are rent. A heavy blow that will be folt more at # distance from thao close up to the oxplesion will certainly result, bat 1 will not bo of a ter to cause serious alarm. The theory of Genor&l Newton regarding the etfect of the “blow up’? is perfectly c notwithstanding the efforts of the alarmists that seek to subvert it, The general procautions taken by the officials o: the works and the police will prevent any accident oc- curring to over adventurous persons who may desire to inspect the scene promaturcly. Such being the cago the public will await the day fixed on for the groat ovent with the utmost confidence, THE EXCITEMENT OVER THE COMING EXPLO- SION—SCARE AMONG THE PROPLE OF AsTO- RIA—A MAY MORNING IN SEPTEMBER—LOOK OUT FOR THIEVES—THE WORK APPROACHING COMPLETION. No dynamite !’” was still the cry at the government works at Hell Gato yesterday, and consequently the workmen were “busy doing nothing,” as the foreman expressed it. In other words they were moving scaf- folding in the tunnels, carrying off implements no longer required in the mine, and doing whatever could bo founa tokeep them out of mischief and in working order ready to handle the anxiously looked for material when it should arrive. Carpenters were employod all day in building and getting into place a serios of buxes inade of one inch pine plank, cach about twelve feet long and une foot square inthe clear, These will be joined together ondwise to form a continuous trough or case which will run from tho bottom of the shaft up to the surface of tho ground and thence across to the vombproof structure containing the battery. Ra- diating from the end of this box, which rests upon the floor of the shaft, will be smaller boxes ot a similar character, ono leading to the mouth of each heading. * Through each of these sinaller oncs the ex- ploding wires from its own heading will be thrust in order to keep them from injury from falling bodies or othor causes, All the wires trom tho entire 180 groups will thus converge in the Jarger box or pipe and puss through it to tho battery, Tho siphon, already do- seribed, was also completed yesterday. THE DYNAMITE comING, Late in the afternoon a messago was received trom the contractors stuting that tho dynamito was then being shipped and would be delivored at an early hour this morning. Should it arrive without acciaent, tho work of charging the holes, which is pot yet com- pleted, will at once be proceeded with and at the same time the Olling of the primers or explodent cartridges will go on in the littie temporary sheds erected for that purpose at four different points upon the grounds. Snould nothing unexpected happen, the charg- ing, putting in the primers and fivoding tho excuvation will probably all be completed by Saturday night In that case the expiosion will occur on Sanday next, as General Newton will not permit the mine to remain one moment longer than is necessary after the arrangomenss shall have been com- pleted. Tho Goneral has beon much annoyed by let- tors from persons seeking to verily the correctness of statements made by newspapers to the elfect that the “big blast’? would occur on cortain days. never been able todo more than conjecture the time himself, aud bis guesses have ull been thrown out of joist by the delays of the contractors referred to. Should the expected materiai arrive this morning, however, he thinks the blast will oceur on Sunday, uF Monday ut furthest, Notwithstanding the wide adver- Usement given to the fact that no visitors are admitted, hundreds visited the place yemerday, and all tho Vigilance of the one-armed ‘guardian’ of the spot was required to keep them from sealing the low fence which shuts the sightseers were not a few ladies, who, despite the dangerous character of tho Jocality, woro exceedingly | disappommted in not being able to gain admittance, The pleas on which admission is asked varied ag they are amusing, but the instruction the watch. mah are peremptory, aad no one passes him who has not the special permission of Gonerai Newton or Cap- taio Mereur. WHEN THR MXPLOSION WILL HAPPEN, Notice of the time of the explomon will be given by the oilicials’ just us soon as they with any degroe of certainty can tell when it will occur, 16 will be udver- tised in the newspapers and aotives will be posted up at prominent points in the viciwity. Porsons living very close to the reef will bo notified by men sent directly to their houses, Arrangements for the preser- vation of order on the oceasion Lave been almost com- pleted. On the shore a force of some fifty soldiers Jrom the fortifieations i the barbor will be drawn up jo jia@ & sort distance trom the shalt to keep at @ proper distance the. throng ot curious people whe will doubtless be ou bend, Police Captain Woods of Long Isiand City will also de- ‘wil about tuirty policemen to aswiwt the military. On the river red tags will be waved to notify veswels of tho dunger and when the river opposite the mine i irced of uli cratt four steamboats, each with w few United States troops on bourd, will block the channel, two being located above aud two below the line of the works Besides this all the New York Harbor police and the steamboat Squad will be detailed to the scene and will, no doubt, du good service in preventing the wo near 4) proach of tho hundreds ot stall boats whieh will convey sightscors (0 the vicinity of the explowon, The tour sieainboats roterred to Will have on board persons in- vilou by the government officials vo witness the blast It is oxpectod that many prominent officials trom Washington will be presont on the occasion, as Gen- in the grounds, Among | eral Newton will send invitations thither as soon as the time for the event can be fixed. The steamboata will cach lea different pier on tho Kast River on th ay we we pene with the invited guesia A im number of tickets have been printed for the oceasion, and they will be judiciously distributed. , are printed on fine cardboard, and read as fol- wa Qrerwnsrinaion at MeL OMe EXPLOSION AT HELL GATE, * tember 1876, Seiknane-weh tote Pier, Fast River, at ; Show this card at the boat. : rene rere rs ae eee. senecesene ne: eided upon, The jolly Teuton who dispenses beer just outside the grounds exclaimed yesterday “Mine Gott, I hope dey blow it up on Seterday. Den de growd vill all goom on Sunday, und I vill sell a hoondred kegs of peer!’ ANAIRTY IN THX NEIGHBORMOOD. The forthcoming explosion of Hallet’s Pomt Reef be- ing the all-absorbing topic at the present time, i is but natural to infer that those residing in its immediate vicinity should feel very uneasy as to its probable effects. There is no exaggeration in saying thatin and around Astoria there is idespread fear of danger, and 00 assurances from General Newton will in the east tend to allay The pressed opinions of many engincers that the fect will be vastly different {rom what General New- ton predicts seem to have taken deep hold of the peo ple tu general, and ull are making preparations to avert as far as poasible the expected demolition of Property. : SAVE THB CHIMNEYS. An old gentleman whose dweliing, somewhat remoto from the scene of the expected explosion, boasts ot @ Tuther high chimney, was yesterday seen taking down that nseiul appendage, hiting off the bricks one by one and piling them up in his garden. It was better, ho Said, to take them down safely than have them thrown down, and ay hag crush through the roof of uis house in their fail. Within the grouods on which the government work- shops stand, aod but 100 feet from tho mine, stands a neat two story brick dwelling, with pitch roof, by Thomas Cod night watchman, and family, consisting ‘of & wife and ten children, Belore the and = was eased = by =the government, seven years ago, the house was occupied by the watchman of an oil factory which stogd upon ‘the land, and when it was vacated General Newton permitted Code, whom he then employed as watch- man, to occupy it rent free. lt would be too much to expect this building to withstand tho shock, and the General has notitied Thomas that hd must remove this week. The poor fellow was on the lookout through Astoria zulercay for another dwelling, and the tears stood in his eyes as he spoke of having to leavo the tasteful little edifice he has spent so many years in. ON THR NEW YORK SHORE, Right across trom the reet to be demolished, that fear. modern porlety, and the careless disposition of various household art! indicated the unrestrained babits of a thougbiess olor, elf veiled against the wail in one cornor was strewo sumo straw, which ovidensly rervod jor u bed, & goab was playfully butting ite horns against the weather ‘boardimg in the ,rear wall of the mansion, a troop of ducks waddled promiscuousty aboat the floor giving vent to their peculiar cry, and seated hear a small pine table gazing at thom with acaleulat- ing alr was the man of the house. Ho was about fiity Years old and attired in a blue fanpel shirt much the worse for wear, and a pair of blue overalls, while bis feot, encased in lime burned brogaus, were clevaied upon the table, He gazed carelessly upon the reporter throagh the whiffs of smoke emitted trom a pipe which breathed odors pot ambrostal, as it be were an old ac- quaintance, The man was evidently in a mood of per- fect happiness and sel!-satistaction. “Woll, old map,’ said the scribe, ‘when do you ex- pect to bs blown up?" ‘Aw, begorra, that’s all done with,” said he, phil- osophically, 1 berrid ber last week.’? “Buried what, whe?” “Th’ ould voman, Ye weren’t at the wake ?”” ‘The reporter stated that he now learned for the first time of the decease of the old gentioman’s partner aud roceeded Lo ask whether ho expected any datuage to jis house from the big blast across the ri “Ob, divil a bare,’ between at the pipe, “The —— a cornish ivil knock off anyway.” Lookin ut for the invisible cornices alluded to, the reporter saw a twinkling of tun in the old tellow’s eye “Well, Ldon’t know,’ he ventured; ‘you will get a hard shake here.” “[ wouldn't doubt it, Begorra, everybody shakes me | since I got bounced oif the big pipes.” “You're right on the line of the reef and the rock 1s solid, It’s guess, you know.” “Nico, is it? [don’t care u traneen what it is iv it Keeps 1s distance ay me.” There was clearly nothing to be elicited here, and the reporter departed, leaving the old mau puillng com- placently at his pipe. In Ninety-second street, near tho river, a frame house, two stories high, is being moved on sliding beams along the widdie of the street up toward Second avenue. in Erghty-fitth street, also, a small house 18 being moved in tho saine direction. “Ou, mon,’ ex- claimed a Hibernian car driver yesterday, as ho saw the workinen sliding the buildings aiong, “they're get- Un’ frightened, and no mistaxo, when they*ro movin’? the houses out av the way av uy WHAT AN EXPERT THLY’ Profeseor ut by the merchants of New York to remove some ot Hell Gate obstructions as long ago as 1851, and who, by his own method of surface blasting, succec: much reducing the height of Pot Rock, Fryin Way’s Reef wad halt a dozen others, returned aboat two weeks since irom Charleston, 8. C., where he has been engaged in removing obstructions from the bar- bor. He hives m a neat cottage on the atrect line of the reef to be blasted and only about 200 feet from the shait, Asked by a Hera. reporter yesterday whether he thought there was auy danger to HELL GATE. No. 1—Section of the Main Shaft Showing the Syphon in Position. No. 2—Bombproof Shelter for the Exploding Batteries. and but a Ninety-second little distance from the river in the lofty brick building used for a brewery of lagor beer. Besides presenting a broad side six high to the mine, the structure has three stories under ground filled with barrels of beer. Tho upper story of the wing running parallel with the river is used as an ice house. In winter time ice is stored bere in hage viocks until the piace is filled, aud then water is poured into the chinks until the mass freezes into one solid block of ice, 200 feot long, 75 leet wide aud Zu foet thick. During the summer months this, of course, melts pretty ireely and becomes much reduced in size. The block bow rotnaining in toe room weighs about 5,000 tons, and it has meltod away so that a spaco of four or five feet intervenes between it and the walls of the building all around. The proprietor is very much excited over the proposed blast, which he thinks may cause such a concussion of air us will shake the wails of bis building; and should the immense mass of ice described be given even a slight impetus, there is no doubt that it would slide across the floor and tearing throagh the wails of the building, carry destraction in 1% path like miniature ava- janche. ‘Thinking that the inmates of the House of the Good Shepherd, at the foot of Ninetieth street, built ona rock nearly opposite Hall Point, might naturally feel alarmed, it was visited by the reporter, who saw the venorable Kev, Mother Magdalen. She said sho feared no danger, being asured by Goneral Newton, who called tere’ ines June, that whe and her charge might rest in perfect peace of mind. The Genera! toid her that beyond tho throwing up of a volume of water, with smail fragments of rock, woth- ing would be seon, and that the vibration would bo scarcely perseptibie. Her only cause of anyihing in the shape of fear was about that portion of io building known ag St. Joseph’s class, occupied vy the junior Nquents, and which was found wo be erected ‘on a ck in the rock. Except for that all felt per- foctly secure. Passing across the avenue to St Joseph’s (German) Orphan Asyium, the reverend Mother stated that they, too, felt no anxiety; indeed, so little tear had they that io time of recreation some of the Sisters would indulge In jokes about the matter, one saying she would ascend to tho roof us the most socuro place, and another descend to the cellar, so 2 tho event of the tall of the bailding’ she 1 would save them the trouble of burial Asa measure of procauvon, however, she bad deetded un removing all tho cbildren into t closure or yard. Mr. Loug- wiroet, superintendent of the Hariem bor asked |. Brown, proprietor of tho restaurant ut tuo Ninety- third street ferry, to find bim a suitable place for deburk- ing passengers in the ueighborhood on that day. He was given a landing close to the forry, and imtenus putting ‘on five boats, This point commands one of the finest views to be found, aud Brown will avail bimsel! of the opportunity by having reserved seats on his dock and elsewhere for nis patrons frends, A potice force of 100 mon will be detailed for that neighborhood, 4 MAX WHO 18 NOT aPkalD, The reporter wered up the slope by Nin street, and secing the door of a som du one stery habitation ding opon, he approached it and looked within, Kverything around betokened the home of one free from we silly conventionalities of | pounds of an explosive ten times be apprehended from the explosion he replied most nplaticaily in the negative. Sinco his return he says he has gone down into tho tunnels und carotully exam. med every detail, wud he is fully satistied that the work will be a great success. He was much impressed with the ovidences of extreme carefulness on every hand, and 40 contident does he fee! that the shock will not cre- ate any damage that he bas not remaved even the wost fragile furniture from his house, although it « much closer to the mine than any other. When questioned as to whother the blast would roduce anything in the way of au exhibition for the curious M. Mailletert de: Clared that it would doubtless be a grand and impres- sive sight. He thinks that from the centre ot the cavern a shaft of water and broken rocks will shoot up into the air a veight of 125 feet or wore. This inass, however, be believes, will fall back ito 19 place without damaging anything. Questioned about the effect of the explosion on the cofler dain which rests upon the rect to be domolished the gentleman said its fragments would bo thrown a-considerable distance, but provably in an up- ward direction #0 as to hurt nothing. ‘The report asked M. Maillefert whether ho would remain ia hi house when the blust was exploded, and ho replied that he was not alruld to do so but it Was understood thut tho government officials would not permit any one, in- doors or out, within the cordon of military und police on that day. AN RNGINERR’S PRARS. Mr. W. H. Nanne, late supermtendent of the Costa Rica Railway, who is living in thia city at present, said “T don’t think it possible for any one to even approx- imately estimate the force and extent of a shock from the explosion of » mine of such wagnitude, jor it has never been tried. ‘The blowing up of Blossom Rock, in San Francisco bay, 8 no nore to be compared to 1 than a fire cracker to a bomb; 45,000 pounds of giant powder were aged on it; at Hallott’s Point about 40,000 poweriul 18 dis- tributed through the 3,680 drill hol “You seem to think, then, sir, that tho experiment will be a dangerous one ?"” “*Foat t would not like to yf bat I certainly shail take care not to be in any tall house up town when the mine ts sprung.” “Then you think it dangerous “Weil? —hesitating for « motuent—"I don’t want to act a4 an alarmist, but, to sp ndidiy, | dot"? “You anticipate a severe shock?” “Seo hero’? (describing 4 pian on an envelupe with a pencil), “this 18 Hailett’s Point, which 18 simply the outcropping of a lead of gneiss rock which extends through Astoria, under and across the river, and under a scetion of upper New York. In the heart of this reof, upon which all Asioria and # large sectiun of two wards in New York js tounded, itis proposed to simu- Jato an earthquake, Do you know the consequences of any sudden disturbance of tue toundauons of tall houses, however #light that disturbance really may ber” “Of course.” F “Well, fit your knowledge to my theory aind reflect We are usked to believe that a quarter of « milo rth, which has been converted into a colussal bat- tery charged with the most powerful explosives known, will cramble into fragments without a convulsion. Ie guch @ theory anatural one? Ask any one who has ever worked in mines, where even pow severe concussion, Or let mv give you own experiences. vile Uridging the Matina River, on tho Atlantio section of the Costa Rica Railrond, @ favorite mothod of fishing with ui the explosion ot eight dges of dynamite in the river, The con- sulting from the firing of three of these cartridges tied together was suificient to stun all tho fish within an area of a quarier of a mile square and send them floating helplessly down stream into our nets, My tent was pitched on a lead of rock trom the edge of which the curtridgee were usually thrown into and every explosion was lollowed by a se- Kueh time a charge was exploded, too, a und smull stones were turown up from the river bed, which was In that place, AT LEAST TWELV® FEET HRLOW THE SURFACK.”? “Do you contemplate avy casualty in the vicinity of the explosion itself, Mr. Nanny? “None, unless people in boats are incautious enough to venture near euough to the mine to be struck by the fragments which are certain to be thrown up, Tho danger, in my mind, exists in the convulsion certain to be communicated to the reef, The theory of a tidal wave ix preposterous, There will, of course, be an up- heaval of waier over the miue, from which # certain sweil will arise, but it will subside as quickly og tt orig- mated," “Do you think the exploaton will be a success?” “Lt cannot fail to be; why, you could almost blow a mountain down with the sae amount and quality of material, It will be the end of the rock—and a good many houses which stand on the lead, too. You may be bound if I owned a house in Astoria I would bogin to move out to-day.” Loss OF LIPE ON THE WoRK, ‘The thing that must strike all who are familiar with the magnitude of the undertaking ia the comparatively small sacritice of puman life. Up to the present but six lives were lost, and all through carclessness—two by entering before a biast went off, one by a rock fall- ing through the roof of a shed which he was frequently forbidden to enter, aud the three others on the drill scow jately, The wateh{ul cure and supervision of General Newton and his ussistants had much to do with this, yet many there say that the pablie would have felt very’ un- easy bad they but known the gross carelossness or reckleskness on the part of some pf the employés, and the manner in which they handled the most dangerous explosives. It was but a few day# ago that a car- (ridge fell trom the hauds of one uf men white charging. Not long since sloop, having a supply of explosives on board, Was atichored at night tn Hallev’s Cove, betwoen the Astoria ferry and the steamboat landing at Ravens- wood. Inthe morning as two men in a rowboat were towing ler to the works she was forced by the current into the ferry dock, where she got stuck, anda tug had to be siznalled to take her up to the works, The Passengers on the Various boats may notice on Lite Mill Rock a sinall wooden shed built’ on tho rock, in shape like a tent, and tunocently covered with an advertisement of the “Rising Sun Stove Polish ;”” yet inside that simple and apparently harmlosé stricture 38 stored, immediately over the quantity of uitro-glycerine. The boweprit of ming in contact With it might result in an experince of 118 explosive or non-explasive qualities. Tho lettering of the advertisement was at one time used us bull’s-eyes tor a rifle until the marksman was informed of its contents. A VICTURRSQUE SCENE, No more striking or picturesque sceno can ve found than that presented by the works upon a fair day. Down within the gloomy portals of the tunnel one catches glimpses of dark, gnome-like figures moving busily to and fro by the tlekering light emitted from tiny lamps attached to their heads, like the tra- ditional stars upon the brows of ‘airiey Flashing through the darkness now and then comes a gleam re. flected trom one of the tin cartridge casos being d posed in the rock, and which, by some cu- tious alchemy of "the lamps,’ seem — turned into a bar ot burnighod gold. Guzing thus one almost believes he is looking upon a scene from Wagner's famous trilogy, aud that tho figures below are those of the “Nibelingon” heuping up their gold beneath the bed of the Riune. Tho illusion ts hoighe | ened when the spectator raises his eyes to the biue river flowing above, and turning toward where Big Mill Rock proudly rises above the Water he.almost expects to see the nymphs gracetuily reclining upon its verdant slopes and mocking the dwaris below. The clouds above are reflected on the busum of the sparkling river. Sailing toand tro over the gloomy depths pleasure yachts, with glistening white saila, eieave their way and iil the air with music from the bands upon their decks, mighty Sound steamboats, with the flags of utty nations fluttering from their spars, noble sips, and grimy, bustling, shrieking littic tugboats move ‘by in endless panorama. Here und there on the bright gur- face twinkle Little whirlpools which mark the presence of treacherous rocks below, and near the further shore a long ridge of boiling toum ‘projecting to 1 the river marks the line of the pertlou Beyond tho brilliant blue belt of river thus rises in gentle slope Ward’s Islana, tts vivid verdure forming a veautitul contrast of color with the deep blue of the river on one side, and making on the other a tit- Ung setting for the bright red brick buildings with which itiscrowued. Above all these stripes of contrasting color—the blackness of the Geheuna-like mine, the ray root rock over it, the blue river above, and sull bigber the green slopes and the bright red buridings— stretches a sky usually of sombre hue, which forme a charming background for the picture, and against which even the finest tapered minaret and the #litam lightning rod on the buildings 1s outlined as it drawo with a pencil. A VISIT TO THR WEADINGR Descending into the cavern, at first the tunnels arc bigh und of a good width, From the pillars project jagged. masses of rock down whieh the water from the river above leaks in & constant § one advances further the darkness so dense as to secm palpablo, the tunacis accommodating themselves to the dip of the reef above become steeper and steeper in their descent, until the irightencd visitor imagines he 18 going por- peudicularly down into the biack gulf, in the gioem of which he can see now in the distance a uny, starlike gleam of light where the men ure tolling. e foot slips constantly in a deposit of nud at the bottom of the tunvel, and plush! It is @ pooi of water up to the kuee! The extended hands touch on either side the walls of the rapidly parrowing tunnel, cold and elimy, and the bead strikes the jazged masses of stone that project trom the root, which becomes lower and lower as one advances into the gloomy deep. Jets of water, invisible iu tho darkness, full through the crevices above abd make their presence known by drenching one to the skin. Suddenly a sound hke the distant roar of artillery breaks the deathlike silence aud roverberates through the hollow deep. The workmen are driving a plug back into @ bolo through which the water shot turty feet when the woouen stopper was removed. Twinkiing in the beavy atmos- phere, and retracted by the tailing spray between tho lights, the men seem miles away down in the bowels of Ube carth. The air is heavy with vapor and thick with the smoke of the lamps, which, finding no escape, rolis in a dun cloud ulong the roof, 'so that ove breathes with difficulty, In another minute the lights which seemed so far away are close at band, aud their gleam turns tho sohey reas tho dripping roof into diamonds, and causes the trickling walls te glitter in russet apd silvor, striped where oxide of iron oc- curs with oriiliant bands of carmine, whilo they throw tho Jorms of the miners in grotesque shadows upon the pool below. Now a sullen ir ioe dicates the puBaage overhead of some massive steamer whose revolving paddles cau: ¢ thirty-tour feet of sSuperincumbent water to tremble throughout its ebtire depth. Far within (he numerous holes perlorated in the rocky sides of tue leading, which either elbow touches, the ends of the deadly eurtridges gleam faintly asthe lights are vorne to and fro, Tho men, standing kuee deep in water and drenched to the skim, are about to fill «hole. One brawny follow, wh livid, though masay, jaw implies that tho wholesome sun hever @ he toils, seizes a Jong pole and thrusts ii length juto the orifice. Withe drawing it he names the mze of cartridge re- quired, and, his assistant selecting one from a boxtul Closy at hand, ft is thrust into the hole eudwise and quickly pushed into its place at the tnner extremity. Another, tiled with a less powerful compound, follows the tirst, and so on until the shining ond of the last curtridge shows that the hole is filled almost up to the face of the rock, Then a pine plug is inserted, bearing the number of the hole, and the workmen plash through the water to the next. A more weird and im- ve Beene can bardiy be imagined, and ite effoct the visitor is rendered ntense by the realization of the terrible force compressed around him, which is so soou to crumble the solid rock which withstood the storms of thousands of years into and which might by the turn of # caress workman's hand lau hita and all those about him into eternity #0 quickly that they would not know that it bad come. DELAY IN DRLIVERING THE DYNAMITE, A roporter of the Hraatp callodet the office of the Atlantic Giant Powder Company, at the corner of Park place and Church street, last evening, and ithero saw Mr. Varney, the bead of the firm. Ho was asked by tho reporter what was the cause of the dolay of the company in delivering dynamite to the Hallett Point works. Mr. Varney said that there was no delay Whatever in the dehvery more than was neces- sury in Ube course of ordinary preparation to deliver the dybamiie. General Newton’ bad ordered 20,000 poun of dynamite on the 20th of July, and all of that ti been delivered; butin delivering what been rod nee, on just Saturday, there had beea a little dela: there was not cartridges enough sent to them, ey could not send the stuif until 8 was pinced Ih the cuririages. The agreement, or contract, reas that tho dynamite should te delivered between August 15 and September 1, with two weeks of @ margin on any probabie dolay that might occur from the government's propositions, Large quantities of the dyoamite could wot be kept at the manufactory in bulk with any great degree of safety, The factory was some filty inties away, at Drakesville, neur Dover, NX. J. General Newton came on Saturday and ordered’ 15,000 pounas more, and of this amount 2318 pounds bad alreaay been delivered, and Mr. Varney said that 5,000 of 6,000 pounds additional we being shipped yesterday to the Hallew Powe works, and there would, no doubt, be @ delivery of that amount by this (Wednesday) morning- So fur the delay bud been merely trom the lack of curtridgos and way uot the fault of any persen in par- ticular, Mr, Varnoy said that they could not keep great quantities of the dypamiv on hand ahead of the Supply for reasons which would suggest themselves to any intelligent pei CLEANING OUT THE SLUMS. Captain Byrnes, of the Viltoonth precinct, last night raided the bouse No. 26 West Fourth street, kept by Joun Bernascotti, alias Tarabaldi, and arrested the proprietor and sevon females, ail of whom were locked up in the Mercer street tion house, The place has long been notorious as a vile bawdy house, but the pro- privtor has manuged to keep clear of the police. eflecting the raid Captain Byrnes was obliged to resort to bo little degree of strategy In order to get, inside the house, Tho prwoners will morning, Trial of General Babcock for the Safe Burglary Conspiracy. ————— CHARACTER OF HE JURY EMPANELLED Republican Fears for the Result in Ohio. FROM OUR REGULAR CORRESPONDENT. Wasurxorox, Sept, 19, 1876, THE SAVE BURGLARY CONSPIBACY-—TEIAL OF GENERAL BABCOCK COMMENCED—A JULY WHICH IS LIKELY TO DISAGREE—MR. ALEX- ANDER ON THE CONSPIRACY AND EX-CHIEV WHITELEY ON THE TESTIMONY. Wo have entered upon the second series of the murky plotting and counterplotting of detectives, outside law- yers and witnesses which has marked all the phases of the sate burglary trial heretofore and the consequent indictinent of General O. E. Babcock, the President’a lato private secretary, From tho firet the gamo has been on ono side or the other to reduce the testimony and witnesses to inextricable contusion and incredibility, Most admirably have they suceecded, 1t amounts almost to art and has all the outlines of adaptability to the construction at least of stage ruscality and intricacy. ‘The first part of the farce, for such it is, was to-day consummated in the selection of aso calied jury. ‘The governtnent was handicapped by the provisions of law beyond which the presiding Judge, Humphroys, could not ga in the aliowance of but three challenges, whilo the defence were allowed four, At first counsel claimed that thoy were entitled to eight challenges each, but tho Court ruled not. ‘These wero soon exhausted, and some, though not objectionable, yet certainly not the most acceptabie, jurors were selected, The frat who ‘was sworn in and passed, if not in bad taste, would, ordinarily, at least, have put impartiality to the blush, for be proved to bo no other than Walker Lewls, colored steward at the clubhouse where the conspirators im the safe burglary assombied on the night of April 23, 1874, of which conclusive te timony has been taken beforo tho Congressional com- mittee, Next was Jonn W, Freeman, colored, who has worked under General Babcock ou tho ‘public grounds, and last was William Ferguson, who, in the estimation of unprejudiced lookers-on, was sure to hang tho Jury ashe seemed anxious to got on it at all hazards for the sake of the revenue it brought. Mr. Columbus Alexander, the person most interested in the trial, and who was most affected by tho alleged conspiracy, was interviewed in regard to tho jury. Ho is an old citizen of Washington, but says he does not know them and appeared very much dissatisfied with tho'different cloments composing it So far as thets probable bias 1s concerned he apprehends even now thattho jury will disagroc and has almost made big mind up to it. He tried hard to keop colored men off, as be thinks they would not be likely to decide under- standingly on tho evidence. What he expects to prove in regard to General Babcock's guilt ts that he was in- terested in vreaking him down by destroying his cred- ibility during tho investigations which were made by Congress into District alfairs, in which Mr, Alexandes and bis friends were important and persistent wit- nesses against tho thon existing Board of Publi¢ Works, of which Genoral Babcoek was Super- vising Engincer in tho mattor of measuring tho improvements made about the public buildings and grounds. It appears that they were striving to show falso measuroments on the part of General Babcock, and also that be was drawing money from the ‘Treasury before the work was actually done. Mr. Alexander says:—‘*Wo were tracing the corrupt paymont of $97,000 byw firm of contractora named DeGolyer & McClellan, and we followed up to ox Governor Shepherd's oflice, whero a partner of his re- colved « large amount of the money. 1t was necossary thon,’’ he adda, ‘to strike mo down, and hence thoy gotup the safo burglary business to show tho com. mitteo what sort of aman I was, and an effort was made to break down the investigation, but I turned too quickly én them by going into the safe burglary matter, which the committce took up at once, and thore we beat them.’” The most important witness wili be Mr. H. H. 0, Whitley, late Chief of the Treasury Department socrot Service, who is charged with patting up the whole con, spiracy job, He said to Mr, Alexando! ‘I want to cloar myself and want to toll the whole truth. I wag employed to work itup. I was not to be benefited, ‘but I was doing it forthe mon who wero to be pene- fited.”” General Babcock’s complicity is charged to have con- sisted principally in bi 6 caused ex-Solicitor Ban- field of the Treasury Department to telegraph to Whitley tn effect the following :— “B, wants to 800 you. Come over,”” “Somerville, a New York lawyer, also on trial, pres pared the depositions of Michael Hayes and of William Benton, alias Walter Brown, now in jail, to convict me,” suid Mr. Aloxander, foclingly, as he turned over tho pages of printed evidence, and pointed to th lengthy depositions in the case. One of the worst fea tures of the present by-play is the activity of a Mr. A. B, Williams, a lawyer, who is supposed to havo fixed up tho jury in the Green trial and who is charged with mauipulating juries for counseL He was indicted ag ono of the conspirators, and was with Chief Detestire Clarvoe and Major Richards, Superintendent of Police, on the night of the sale burglary, and, with ex-Districs Attorney Harrington, followed up the burglars te Columbus Alexander’s house. The prinvipal burglar’s amo was Benton. r, Williams bas beeu busy all day gotting up a list of and looking afser the jury. District Attoracy Wells, on being asked whether all the witnesses for the government were subpwnaed, said thoy were not. Ho expresses himself as being entirely satistiod with the jury, and thinks, all things considered, they havea very fair lot. He turtber an- nounced bis opinion of the trial by saying, ‘It witl be 8 quick, strong trial on both sides.” Mr. Whitloy wag later ongaged with him privately im the Log otgped of questions which are to clicit his testimony in the case, Tho triai hus created a great deal of excitement quarters, and 14 ramifications will bo found to extend lo ex-ollicials if not circumseribed by flatting out of witnesses, understood to be busily engaged to-night in giving his personal attention to the careful preparation of the safe burglary trial so os te wee that the governmeat will not im any way be af fault wor overlook anything which should properly be Gone by it to protect its interests and secure a full and fair trial by bringing out ail the testimony which should be developed by it BEPUBLICAN FEARS OF THE RESULT IN OHTO—~ A CRY FOR MORE MONEY—CORPORBATIONS TO SEND THK REQUIRED BARREL. i A great deal Of solicitude is manifested hero among republicans in rogard to tho campaign in Ohio, Among those who have watched its conduct there closost as wellas what Is done here there is apprehension fel, that everything is notall right and that a weakness Provails in the management of 1t im some importang respecta, In support ot this it ig recalled by those most conversant with tho history of the thing that last year, wheh Obio had become the most important State in the elections, there was some difficulty about providing for the campaign expenses, and until near election day the Chairman of the State Executt: committee continued unreinforced with suficior funds for the campaign, Considerable dissatisfaction jationai Executive Committes grew out of* d ox-Assistant Sect the Intorior ps ot, Was charged with being the obstucle to Unbio’s thrifty condition, When the charge was directly to him he acknowledged that he did not think Obto ought to Nave any more money, as sho already had $10,000, and when he was Chairman of the State” Executive Commitioe, that was sufficient ta run the campaign.’ Upon being —_ remindod that ehange haa taken place in the time of her election and that Ohio bad thea the place of first ume ai diiticulty tha which was majority, almost after she bad been given up by her friends. ‘Though it is claimed she has a republican majority ranging trom 25,000 to 50,000, it 18 feared by the republican that some such thing is Bow at and ere is great danger tho election will be i the democrats may carry it by a surprise A nt 14 to bo nade mone to seo that etic canvass and victory. wanting persons Who oppose it because they are imter- ested in the othor States more largely than they are ta Obio. Tho National Executive Committee ure blamed with doing more for Indiana than Ohro, and with bay. jou signified to the leaders in the latter State that she through, rrcips acoatmoniehaaa| 8 oho strong enough to helo herself