A true movement of carriages is dependent upon the amount or wearing power of their bearing surface, how this surface is disposed in reference to the strain to be resisted, and the conditions under which the sliding surfaces move; that is, how kept in contact. The cutting strain which is to be mainly considered, falls usually at an angle of thirty to forty degrees downward toward the front, from the centre of the lathe. To resist such strain a flat top shear presents no surface at right angles to the strain; the bearings are all oblique, and not only this, but all horizontal strain falls on one side of the shear only; for this reason, flat top shears have to be made much heavier than would be required if the sum of their cross section could be employed to resist transverse strain. This difficulty can, however, be mainly obviated by numerous cross girts, which will be found in most lathe frames having flat tops.
"It isn't that," said Isidore. "I've got a fine head for figures, and some of the numbers of these notes strike me as familiar. They are identified in my mind with some sensation or tragedy. It seems to me--ah! got it!"
ONE:"It happened at Landen on Friday, October 9th, in the train with wounded which arrived there from Brussels at about noon, when food was being distributed."
ONE:"Well, I can and I can't," Lawrence said thoughtfully. "I'm puzzled, of course, and I am very much interested in this kind of thing. But really I am puzzled over one of the most remarkable coincidences that ever happened in the experience of a man who has made a pretty penny out of coincidences. In this instance 'the long arm' has taken a form that is positively uncanny."
TWO:I roamed about aimlessly in a scorching heat. Whither? I did not know myself. I did not know Louvain and met nobody whom I might ask something. I came near a couple of streets that were only ruins; the walls collapsed against each other and filled the roadway with rubbish, so that sometimes I could not see whether I walked on or beside the place where the houses used to stand.
THREE:For a half century past no considerable change has been made in engine lathes, at least no new principle of operation has been added, but many improvements have been made in their adaptation and capacity for special kinds of work. Improvements have been made in the facilities for changing wheels in screw cutting and feeding, by frictional starting gear for the carriages, an independent feed movement for turning, arrangements to adjust tools, cross feeding and so on, adding something, no doubt, to the efficiency of lathes; but the improvements named have been mainly directed to supplanting the skill of lathemen."You must have your comic relief to every drama," he said. "We haven't had much humour up to now, but that is coming. By the way, I hope your Continental friend is not subject to apoplexy?"
