DESTRUCTION OF THE GREY GORGE BRIDGE.

New Zealand Times, Volume XXXI, Issue 4802, 12 August 1876, Page 2 (Supplement)

DESTRUCTION OF THE GREY GORGE BRIDGE.

The Grey Hirer Aryus gives the following particulars respecting the collapse of the Grey Gorge bridge : When first the news reached town it was a long time before people would credit that such a misfortune had occurred. The work had been so carefully superintended, and so faithfully built, that it seemed almost impossible that any' accident could happen to it; but when the actual nature of the calamity was realised, it was not too much to say that a general feeling of regret was created throughout the town, not so much at thejloss of money which the accident involved, but at the delay that must now necessarily ensue in employing the railway upon its original purpose—the conveyance of coal to the port. The bridge was all but completed ; in fact, it only required the flooring and rails to be ; laid. Everything about it appeared to be in perfect order. The superintendent of the work, Mr. R. J. Johnston, had succeeded in securing a perfectly even tension on the wires ; the heavy timber lattice work had been well and truly put together, and to all appearances, and according to the design of tho engineer, the bridge bade fair to last for half a century or more. And yet at four o’clock yesterday morning the anchor plates on the north side of the bridge snapped, causing, of course, all the suspension wire connected with them to carry away, and the whole structure collapsed and fell into the river. When first tlyT noise was heard, some of tho residents at *Brannerton thought that the Brunner coal mine nad caved in, some thought that a great land slip had taken place, but none thought for a moment that the bridge had given way. The destruction is complete, with the exception that the wires can be recovered, but all the woodwork, constructed as it was of the best black birch, is knocked into match wood. Great beams are tom asunder, iron bolts and braces doubled up, and nothing has escaped except the piers at each end, which have sustained no damage, except that the saddle plates, over which the wires passed, have tumbled off, but they can be easily replaced. As already stated, the cause of this catastrophe was the breaking of the anchor plates on the south side. To make the occurrence intelligible to our readers we may explain that the cable, or collection of wires from which the roadway of the bridge was suspended, were attached to a block of cast iron imbedded in the rock, and placed in such a position that unless the iron gave way the suspending wires must remain firm. These iron plates were 4ft: Sin, long, sin. thick, and 12m. wide, and had in the centre a raised rib or backbone, as one may say, oin. by Sin., along the length of the plate. In this plate there were thirteen holes, through each of which an iron was placed, having a nut screwed at the back of the plate, and a hook in the front, to which a portion of the wires was affixed. The whole strain of course was upon the iron plates, which were of cast-iron, and it proved too much for one of them, which broke off nearly in the middle, and the extra and sudden shock to the other one produced the same disaster. The plates were cast at the Greymouth foundry, but it is fair to say that the fracture in each case shows that the castings were good, and of good metal, and, as yet, we do not think that any blame will be placedupon them. Theaccident appears to have arisen from a miscalculation as to the strain which the anchor plates were capable of sustaining. And it may be said that they should have been of forged, instead of cast iron; anyway, a great mistake has been made, and the only gleam of comfort there is about the whole business is, that the accident happened when it did. Had it occurred in the daytime, when about twenty men would have been at work upon the bridge, and perhaps a number of pedestrians, a fearful loss of human life would have been inevitable. Thank Heaven no life has been lost, but the disaster is in every sense a serious one. We may estimate that at least £SOOO worth of work has been destroyed, and that many months must elapse before the bridge can be re-erected. This means a very serious check to the coal trade which, but a day ago, appeared to be on the eve of vigorous development.