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quality. Annealing is carried out with the object of mitigating strains if they exist, but with the danger, that you may, if not very careful, undo, or partially undo in the annealing, the benefits arising from oil-hardening.
You will no doubt expect to hear that the tube is tested, and this is so, as far and as well as circumstances will permit. A gun forging is not like a cheese, you can't put the "taster" in where you will and as frequently as you will; for this obviously would ruin the forging for the purpose for which it is intended. Such testing would be open to the objection that used to be made when it was suggested a needle should be tested, which was, "It can't be done, for if it bends it is no good; if it breaks it is good; but you have destroyed your needle in ascertaining its goodness." There are only two places from which you can afford to take test specimens of a gun-tube, and these are from the two ends—the breech end and the muzzle end. From these places, by making the tube longer than is needed for the gun, specimens can be taken. A set of conditions to be fulfilled by these test pieces, was drawn up after much thought; among these tests were comprised those for extension, for ultimate strength, neither too "high" nor too "low," and for the power of bending over a certain size semicircular pressor, under a steady pressure. The large steel manufacturers who were in a condition as regards "plant" to make the heavy forgings needed (with one exception) said, "We have made the forgings, they will not pass the tests; it is not the forgings which are in fault, but the tests which are too high, these must be relaxed." Gun manufacture was in danger of being altogether stopped.
Evidence was taken from the manufacturers, and it was found they were not unanimous in the nature of the alterations they desired. One man was content with test A, but held test B in abhorrence, while another had no objection to B if he could but be relieved of A. After conference, it was determined that in the then state of the manufacture, the tests should in certain points be relaxed, and greater ranges of elastic limit and of ultimate strength were admitted. I am glad to say, as time has
