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FORE:He spoke furiously under his breath, with the veins standing out on his forehead. He seemed to have almost forgotten the presence of Prout. The next moment he was quiet and smiling again, but Prout was not deceived. Once that man was free he would never go back on his word.

FORE:"Amazing," Bruce cried. "That is exactly what did happen. But how could you possibly have known that considering that until an hour ago not a soul knew of it, not even Hetty!"In constructing patterns where it is optional whether to employ cores or not, and in preparing drawings for castings which may have either a ribbed or a cored section, it is nearly always best to employ cores. The usual estimate of the difference between the cost of moulding rib and cored sections, as well as of skeleton and cored patterns, is wrong. The expense of cores is often balanced by the advantage of having an 'open mould,' that is accessible for repairs or facing, and by the greater durability and convenience of the solid patterns. Taking, for example, a column, or box frame for machinery, that might be made either with a rib or a cored section, it would at first thought seem that patterns for a cored casting would cost much more by reason of the core-boxes; but it must be remembered that in most patterns labour is the principal expense, and what is lost in the extra lumber required for a core-box or in making a solid pattern is in many cases more than represented in the greater amount of labour required to construct a rib pattern.