I next took specimen No. 3 and subjected it to a careful annealing, taking perhaps two hours in the operation. Although it is a 1-1/8 bolt and has V threads cut upon it we were unable to break it, although bent cold through an arc of 90°, and probably would have doubled upon itself if we had had the means to have forced it. Now what does this show? Have the crystals been obliterated by the process of annealing, or has only their cleavage been destroyed, so that when they break, instead of showing brilliant, sparkling faces, they are drawn into a fibrous looking mass? The latter seems to be the most plausible theory, to which I admit objections may be raised. For my own part, I am inclined to the belief that the crystal exists in all iron which is finished above a bright red heat, and that between that and black heat they are formed and have whatever characteristics circumstances may confer upon them, modified by the action of agencies heretofore mentioned.
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