3445. Babbitt's Anti- Attrition Metal

3445. Babbitt's Anti- Attrition Metal. Melt 4 pounds copper, add by degrees 12 pounds best quality Banca tin, 8 pounds regulus of antimony, and 12 pounds more tin while the composition is in a melted state. After the copper is melted and 4 or 5 pounds of tin have been added, the heat should be reduced to a dull red, to prevent oxidation; then add the remainder of the metal as above. In melting the composition, it is better to keep a small quantity of powdered charcoal on the surface of the metal. The above composition is called hardening. For lining the boxes, take 1 pound of this hardening and melt it with 2 pounds of Banca tin, which produces the lining metal for use. Thus, the proportions for lining metal are 4 pounds copper, 8 pounds regulus of antimony, and 96 pounds Banca tin.

3446. Gongs and Cymbals

3446.   Gongs and Cymbals. The secret method employed by the Chinese for working the hard brittle bronze used for making gongs and cymbals, seems to be solved by the fact that the bronze of which these instruments are made, consisting of copper alloyed with about 20 per cent, of tin, and almost as brittle as glass at ordinary temperatures, becomes as malleable as soft iron, if worked at a dull red heat. This discovery was recently made in Paris, by M.M. Julien and Champion, the result of experiments at the Paris Mint.

3447. Phosphorus Bronzes

3447.    Phosphorus Bronzes. A great advance has lately been made in the construction of bronzes, by the addition of a small percentage of phosphorus, although the precise function of this substance has not been hitherto well understood. According to Levi and Kunzel, however, one cause of the inferiority in bronze consists in the constant presence of traces of tin in the state of an oxide, which acts mechanically by separating the molecules of the alloy, thus interposing a substance which in itself has no tenacity. The addition of phosphorus reduces this oxide, and renders the alloy much more perfect, improving its color, its tenacity, and all its physical properties. The grain of its fracture resembles more that of steel, its elasticity is much augmented, and its resistance to pressure sometimes more than doubled. Its durability is greater, and, when melted, it is of greater fluidity, and fills the mould in its finest details.

3448. Fontainemoreau's Bronzes

3448. Fontainemoreau's Bronzes. There is a kind of bronze known as Fontainemoreau's bronze, in which zinc predominates. It is said to answer well for chill moulding, that is, 'for pouring in metal moulds, by which method it is rendered very homogeneous. The crystalline nature of the zinc is entirely changed by the addition of a small proportion of copper, iron, etc.. The alloy is hard, close-grained, and resembles steel. Moreover, it is easier to file than either zinc or copper. The following table presents the proportions in use: