185 



BLAST FURNACE. 



BLASTING. 



186 



(' Commentaries,' b. iv. c. iv.) All these heads, except the first, seem 

 to spring immediately from the root-sense of the word blasphemy, as 

 they are that hurtful and insulting speech which the word denotes. 

 Blackstone (' Comm.,' b. iv. c. iii.), speaking of offences against the 

 Established Church, says the punishments were "not for thinking 

 differently from the National Church, but for raiting at that Church 

 and obstructing its ordinances ;" and we suspect, that whenever the 

 common law was called into operation to punish persons guilty of the 

 first of these forms of blasphemy, it was only when the denial was 

 accompanied with opprobrious words or gestures, which seem to be 

 essential to complete the true crime of blasphemy. Errors in opinion, 

 even on points which are of the very essence and being of religion, 

 were referred in England in early times to the ecclesiastics, as falling 

 under the denomination of heretical opinions [HERESY], to be dealt with 

 by them as other heresies were. There is nothing in the statute book 

 under the word blasphemy till we come to the reign of King William III. 

 In that reign an Act was passed, the title of which is " An Act for the 

 more effectual suppressing of blasphemy and profaneness." It stated 

 that, " Whereas, many persons have of late years openly avowed and 

 published many blasphemous and infamous opinions contrary to the 

 doctrines and principles of the Christian religion, greatly tending to 

 the dishonour of Almighty God, and may prove destructive to the 

 peace and welfare of this kingdom ; wherefore, for the more effectual 

 suppressing of the said detestable crimes, be it enacted, that if any per- 

 son or persons having been educated in, or at any tune having made 

 profession of, the Christian religion within this realm, shall, by writing, 

 printing, teaching, or advised speaking, deny any one of the persons of 

 the Holy Trinity to be God, or shall assert or maintain that there are 

 more gods than one, or shall deny the Christian religion to be true, or 

 the Holy Scriptures of the Old and New Testament to be of divine 

 authority," &c. These are the whole of the offences comprised in this 

 Act. The penalties are severe : disqualifications ; incapacity to act as 

 executor or guardian, or to receive legacies ; three years' imprisonment. 

 (Stat. 9 Will. III. c. 35.) As to its main provision, this Act remains hi 

 force; but in 1813, the number of persons who openly avowed that 

 they did not consider the doctrine of the Trinity as possessed of suffi- 

 cient support from the words of Scripture when truly interpreted, to 

 deserve assent, having greatly increased, and large congregations of 

 them being found in most of the principal towns, several clergymen 

 also of undoubted respectability, learning, and piety having seceded 

 from the Church on the ground that this doctrine as professed in the 

 Church was without sufficient authority, a Bill was introduced into 

 Parliament to relieve such persons from the operation of this statute, 

 and it passed without opposition. This Act, which is commonly called 

 Mr. Smith's Act, after the name of the late Mr. W'illiam Smith, then 

 member for the city of Norwich, by whom it was introduced, is stat. 

 53 George III. c. 160. The last prosecution for blasphemy was that of 

 Mr. Moxon, in 1841, for issuing an edition of Mr. Shelley's ' Queen 

 Mab.' The prosecutor was a person who had himself been convicted of 

 libel, and he retorted by putting this almost obsolete law in action 

 against Mr. Moxon, who was convicted, but whose sentence was merely 

 nominal. 



BLAST FURNACE. [FURNACE ; IRON MANUFACTURE.] 

 BLASTING. The article MINING describes briefly the usual mode 

 of removing masses of rock, in such engineering operations as relate to 

 excavations. This mode consists in the insertion of gunpowder into a 

 ^ mall opening bored in the rock or stone, and firing this powder by means 

 of a train and a slow-match, or by a safety-fuse. The present article 

 relates to the much more effective employment of electricity, as an 

 agent for igniting the gunpowder. The change is not in the explosive 

 material employed, but in the mode of igniting the material, and in the 

 vast scale which this modification enables the engineer to adopt. To 

 those who Jjave only a slight acquaintance with the nature of galvanism, 

 this igniting power is a great mystery ; but it may be readily explained 

 thus : So long as a galvanic current can travel along a wire uninter- 

 ruptedly, its progress is silent and harmless ; but if the continuity of 

 the wire be broken, or if anything occurs to interrupt the current for a 

 small interval, intense heat and disruptive action take place at that 

 spot, quite sufficient to ignite gunpowder if placed there. The arrange- 

 ments therefore are such as to enable the wires of a galvanic battery to 

 come nearly in contact at the place where the gunpowder is deposited 

 for blasting. 



Colonel (afterwards General) Pasley, after many useless attempts had 

 been made to remove the sunken hull of the " Koyal George " at 

 Spithead, conceived that gunpowder might be carried down, by the 

 aid of men descending in a diving-bell, and deposited in a water-tight 

 vessel close to the ship, where it might be exploded by means of a 

 ^ilvunic current conducted by wires from an apparatus placed in another 

 chip at some distance. The Admiralty having given the requisite permis- 

 sion in July, 1839, Colonel Pasley proceeded to form cylinders for con- 

 taining the powder, and to provide electrical apparatus, boats of various 

 kinds, a diving-bell, divers with water-tight dresses, and to make all 

 the arrangements contingent on such a novel enterprise. The diffi- 

 culties he met with were numerous, but he conquered them one by 

 one ; and at length, on September 23rd, he succeeded in exploding 

 2160 Ibs. of powder, contained (under water) in a cylinder affixed to 

 utaide of the hull of the sunken vessel. A second charge of 

 il.s. was fired on October 15th. The effect of each explosion was 



to shatter considerable portions of the ship, which portions were after- 

 wards attached to chains and cables by divers who went down in 

 diving-dresses, and then hauled up by men working at capstans above. 

 The brass guns recovered by these means had a money value more than 

 adequate to the whole cost of the operations ; the wood recovered was 

 chiefly placed in museums, or wrought up into articles of curiosity. 

 Many different explosions, and a long series of auxiliary operations, 

 were necessary to bring about this result. 



The first application of the same agency to the blasting of rocks for 

 engineering purposes was due to Captain Paris, an engineer at Boston, 

 in the United States. Excavations were made in a rocky bed for the 

 construction of quays and docks at that place ; and the removal of the 

 submarine rock was effected by galvanic blasting. The gunpowder was 

 used in various quantities, from four to sixteen ounces, enclosed in air- 

 tight tin canisters. The copper wires were inserted in the canisters ; 

 and these, as well as the powder, were secured by a waterproof compo- 

 sition. A hole was drilled in the rock for the reception of each 

 canister, by a workman who descended in a diving-bell ; and after secu- 

 ring the canister in the hole, and connecting all of them with a galvanic 

 apparatus, a current exploded the gunpowder and blasted the rock. 

 In the spring of 1842 the galvanic method was applied, under a modi- 

 fication introduced by Mr. Roberts, in blasting the rock of a quarry 

 near the cathedral at Glasgow. In the same year some rocks were 

 blasted under water, to aid in the reduction of a waterfall belonging to 

 Lord Panmure, on the North Esk, with the view of rendering it 

 accessible to salmon. In the autumn of the same year, the same 

 agency was employed in making some excavations for the new harbour 

 at Dunbar. 



The experiment, however, which tested to the fullest extent the 

 value of this system for engineering purposes was made by Mr. (after- 

 wards Sir William) Cubitt, near Dover, in January 1843. The occasion 

 for it thus arose : The six or seven miles intervening between Folkstone 

 and Dover exhibit a continued series of bold cliff- works connected with 

 the South-Eastern Railway ; and it was on part of this course that the 

 necessity occurred for a process of blasting on an unexampled scale of 

 magnitude. Proceeding from Folkestone with these cliff-works, it was 

 found that a bulky promontory, called the Round Down Cliff, stood 

 directly in the way. It was first attempted to tunnel through this 

 cliff ; but the soil being unfavourable, the idea of removing the cliff at 

 one blast by gunpowder occurred to Mr. Cubitt, the company's engineer. 

 The arrangements for the explosion were thus made : A horizontal gallery 

 was excavated through the cliff, extending for about one hundred yards 

 parallel with the intended line of railway, in a direction nearly east 

 and west. Cross-galleries were driven from the centre and extremes of 

 this main gallery. At the end of each cross-gallery a shaft was sunk, 

 having at its bottom an excavated chamber, eleven feet long, five feet 

 high, and four and a half wide. In the eastern chamber was deposited 

 about 5000 Ibs. of gunpowder, in the western 6000 Ibs., and in the 

 central 7000 Ibs., making about 18,0001bs. in all, or more than eight 

 tons. The gunpowder was packed in bags ; these bags were placed in 

 boxes ; loose powder was sprinkled over the open mouths of the bags ; 

 and the bursting charges were placed in the centre of the main 

 charges. The distance of the charges from the face of the cliff varied 

 from about fifty to seventy feet. These being the underground 

 arrangements, those for firing the charge were as follow : Oil the 

 surface of the ground, behind the cliff, was a wooden shed for con- 

 taining three galvanic batteries ; each battery consisting of eighteen 

 of Professor Dauiell's cylinders, and two common batteries of twenty 

 plates each. The wires from these batteries communicated at the 

 other end by means of a very fine wire of platinum, the red-heating of 

 which by the passage of the electric current would suffice to ignite the 

 powder. The wires, covered with yarn, were extended on the grass to 

 the top of the cliff, and then falling over the edge, were carried to the 

 three excavated chambers, and placed in connexion with the charges. 

 The wires were each about a thousand feet in length. All the passages 

 and entrances to the powder-chambers were ' tamped,' or stopped up 

 with dry mud, rammed down hard. 



At two o'clock in the afternoon of the 26th of January, all the pre- 

 parations being ready, three engineers worked the three batteries 

 simultaneously ; the three wires conducted the electric current to the 

 three chambers, and the mighty explosion took place. Many per- 

 sons expected that noise, smoke, and fragments hurled to a vast 

 distance, would accompany the explosion ; but such did not occur. The 

 rock seemed almost as if it had exchanged its solid for a fluid nature, 

 for it glided downwards into the sea in one body. Sir John Herschel, 

 who was one among many scientific men present, in a communication 

 to the ' Athenceum ' shortly afterwards, says, " Of the noise ac- 

 companying the immediate explosion, I can only describe it as a low 

 murmur, lasting hardly more than half a second, and so faint, that had 

 a companion at my elbow been speaking in an ordinary tone of voice, I 

 doubt not it would have passed unheeded. Nor was the fall of the 

 cliff (nearly 400 feet in height, and of which no less than 400,000 cubic 

 yards were, within an interval of time hardly exceeding ten seconds, 

 distributed over the beach on an area of 18 acres, covered to an average 

 depth of 14 feet, and in many parts from 30 to 50) accompanied with 

 any considerable noise, certainly with none that attracted my own 

 attention, or that of several others similarly stationed, with whom 1 

 afterwards compared notes." 



