112 METALLURGY OF CAST IRON.
like asking, "Was there no swab used?" No, the wetting the joint receives is as if by chance the fellow on the other side of the house wetting down the floor should, in turning around carelessly, throw a stream of water over the joint. I do not wish to be understood as saying that because pigs can be made with such apparent carelessness, rapidity and little labor, the moulder should do the same in making c' open sand" work in a foundry; but nevertheless the principles involved should be studied by those moulders who require a whole hour to make about a dozen cast "gaggers."
flodern moulding and casting of pig metal involve points which the founder can often utilize to advantage. The principle involved in using open grades of sand and having deep floors to afford a chance for excessive moisture or water to pass downward, is one the founder having much c' open sand '' work to do can often well adopt. How frequently do we find moulders making " open sand " castings that " kick " and *l bubble J' in such a manner that, when the castings come out, it is a question whether they came from a foundry or furnace "boil." Drop close grades of moulding sand and adopt a sharp open sand, and use regular moulding sand only where the metal from the pouring basin strikes the flat surface of the mould, and the trouble as above described with "open sand" work in a foundry will decrease. is now drawn out by means of the lifting iron seen at D, Fig. 33. The sow having been removed, the pig patterns are then drawn out by first raising one end with the hand in the recess at the end R until they can be lifted by the center, when they are tossed on to the next bed ready to be set up for another filling of sancl. Some moulders might feelhe metal will have a good chance to is often surprising how rapidly, as about 75 per cent of the heat generated from the solid fuel is utilized. This is attained where one ton of coke will produce one ton of iron; and Sir........................ 2,720 "