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6th September, No. 35, was only received on the Bth instant, and there has of course not been time to test it. The orders as to distribution of the 1047 axles, contained in your memorandum of 25th September, No. 3G, will be duly carried out. I have, &c, The Hon. the Minister for Public Works, Wellington. F. D. Bell.
Enclosure 1 in No. 19. The Consulting Enuineehs to the Agent-General. Sir, — 9, Great Queen Street, Westminster, S.W., 11th November, 1884 Re Defective Axle*. In reference to the various letters received from you on the above subject, wo beg to report as follows: — As we have already informed you, the delay in our report has arisen from our wish to see the broken axles, and to have them submitted to proper tests, before writing on the subject. This has now been done, and we have received from Professor Kennedy the enclosed analyses of the several tests he has made. We will reply, first, to the question contained in" your letter of the 25th August, as to " how the testing and inspection was conducted ?" At Lancaster we had an Inspector, Mr. Harcourt, resident in the town, and engaged solaly in overlooking work going on at the works of the Lancaster Wagon Company. Mr. Harcourt is an experienced man, who has inspected a great many of the locomotives now in New Zealand, as he was our Resident Inspector at Bristol until the stoppage of the Avonside Locomotive Works. Many of the axles were forged under his inspection ; but as he resigned his position in order to start as an engineer, in London, on his own account, the forging of the remainder, and the turning of nearly all, were entrusted to another Inspector, Mr. Lane, who also was engaged solely on work going on at the Lancaster Company's works. There is not the slightest doubt that the axles supplied by this company were duly tested under the drop. The axles made by the Staffordshire Wheel and Axlo Company were inspected by Mr. Austin, our oldest Inspector, who has been engaged in overlooking the work for New Zealand in Birmingham since the very beginning. Mr. Austin certainly had some other work, although not much, to attend to in and near Birmingham, but the Staffordshire Company's works are near his house, and he saw the axles made from beginning to end. The scrap used, both in Birmingham and Lancaster, was closely looked after, and was always of superior quality, being, for the most part, the cross ends of Staffordshire bars, and filled in with bolts and rivets ; and on first discovering that some of the axles made by the Staffordshire Company were .bad, we suspected that trickery had been employed, by which inferior scrap, not taken from the scrap heap, had been substituted. We therefore sent pieces of three axles which had failed, to a rollingmill, where they were rolled down into bars 1£ inches square, and proved to be not only good, but exceedingly good iron, equal to best Staffordshire. In order to test in the same manner the samples received from New Zealand, we had the boxes sent to Birmingham, where the writer stamped each piece. One-half of each axle was sent direct to Professor Kennedy, the other halves being taken to the Patent Nut and Bolt Company, when, in the presence of the writer, they were rolled into li-inch square bars; pieces from these bars were again rolled into \ inch bars, and the pieces, being all properly stamped, were sent to Professor Kennedy for experiment. The tests made by Professor Kennedy show that in all cases the iron used was excellent, the average breaking load of the J-inch bars being 25-9 tons per square inch, with a reduction of area of 40 per cent., the minima and maxima being 23-97 and 27-94 tons per square inch for breaking-load, and 219 and 499 per cent, for reduction. These results are equal to best Yorkshire iron, showing the defect in the axles to have been one of workmanship, and not of material. The crystalline nature of the fracture of the axles, and of the li-inch bars, shows that the iron has been, in many cases, taken too hot from the furnace, and occasionally, as in the axle marked " A," which broke on the ship, has been burnt. This is a fault to which scrap-axles are very liable, as hammermen in England are paid by the piece, and will always (when possible) make their work easy by over-heating the iron. It is also a fault which may readily escape detection, as, of course, only a part of the axles will be defective. For instance, out of one lot of thirty axles tested by the writer at the works of the Staffordshire Company, the first happened to have been bad, and the lot was condemned ; but on further tests having been made, several of the axles were found to be so good that they could not be broken under the drop, and when put under the hydraulic press, bent until the ends met. Had one of these happened to come first to hand, the lot would have been passed, although many of them were bad. The same irregularity in the workmanship is apparent in the axles of other makers, as tested in New Zealand; and this is evident also in those made in Dunedin, one of the two tested requiring nearly twice as much stress to break it as the other. This irregularity is more or less inherent in hammer-worked scrap, and we propose in future to abandon its use, adopting the more costly, but more trustworthy, method of constructing the axles of rolled bars welded under the hammer. In examining the tests of the axles made by the Lancaster Company, it will be seen that the iron, even before being rolled, is of superior quality, and has been sufficiently worked under the hammer, as is evidenced by the silky fracture. We do not think there is the least danger in using
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