their annual visitation of the dockyard. I was honoured with an invitation to confer with Sir George Cockburn, Mr. Sidney Herbert, and Captain Brandreth on a subject of considerable importance; namely, the proving of chain cables and anchors required for the Royal Navy. The question was mooted as to whether or not some permanent injury was done to both by the test strains to which they were submitted before being put on board ship. This was a subject of vital importance. The members of the Board requested me to act as one of a committee to inquire into the subject. I felt much gratified by the invitation and gladly accepted it.

On discussing the subject with these gentlemen that evening, I found that Sir George Cockburn entertained an ingenious theory in support of his apprehensions as the effect of "over-proof" straining of cables and anchors. It was that they were originally in the condition of a strong man who had to lift some heavy weight, requiring him to exert his muscular strength to the utmost; and, although he might perform the feat, it was at the cost of a permanent injury, and that he might never be able to lift the same weight again. This, however true it might be with regard to flesh and bone structures, was scarcely true with respect to mechanical agencies. I proposed a simple experiment with chain cables, which, it occurred to me, would show quite a different result -- namely, that the capability of resisting the severest proof-strain would rise rather than fall at each successive proof of the same chain cable.

To test the correctness of my supposition, we had a first-class chain cable put into the proof machine,and subjected it to such a strain as to break it again and again, until at last it was divided almost into single links. As I expected, the proof or breaking strain kept rising and rising as each successive remaining portion of the cable was torn asunder, thus showing that no injury to the natural tenacity of the chain had resulted from the increased proofs to which it had been subjected, and that the last broken links had been much more resisting than the first. The same class of demonstrative experiments was made with anchors, and other wrought-iron work used in the service. The Admiralty officers were much gratified with the result, as removing a groundless but very natural apprehension, heightened, no doubt, by the suggestions that had been made to the Admiralty, that their standard proof strain was not only too high in itself, but produced permanent damage to what at the outset was of the toughest iron. My system of continued proof-straining was, in fact, another exemplification of the "Survival of the Fittest"!

A very interesting truth came out in the course of our experiments. It was that the chief cause of failure in the links of chain cables arose, not so much from their want of tenacity, or from the quality of the iron, but from some defective welding in the making of the links. To get at this truth, many excellent cables as received from the contractors, as well as veteran ones that had held great ships riding at anchor in terrible gales, were pulled asunder link by link by an intentional destructive strain by the proving machine. An exact account was taken of the nature of the fracture of each. The result was that in eight cases out of ten, the fracture was found to result from a defectively welded part of the chain-link. The practically trained eye could see the scoria which indicates the defective welding. Though long unseen, it was betrayed at once when the link was torn open by the proof strain.

My services on this committee proved a source of great enjoyment to me. I had frequent occasion to visit the dockyards and workshops, accompanied by Captain Brandreth, surveyor-general of the Admiralty landworks, Mr. Thomas Lloyd, engineer-in-chief of the Admiralty, and Mr. Jeremiah Owen, chief of the metal material required in the equipment of the navy I was requested to suggest any improvement in the workshops that I thought would add to the efficiency of the department; and I trust that my recommendations proved of practical good to the service. At the same time, I have reason to know that many of the recommendations of the committee, though cordially acknowledged by the higher powers, were by a sort of passive resistance practically shelved.

I was much amused, when I first went to Devonport dockyard, to notice the punctilious observance of forms and ceremonies with respect to the various positions of officials -- from the admiral-superintendent down the official grades of dignity, to the foremen of departments, and so on. I did not care for all this panjandrum of punctiliousness, but was, I hope, civil and chatty with everybody. I had a good word for the man as well as for the foreman. I received some kind and good-natured hints as to the relative official

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