Curiosities of the Magnet.

New Zealand Graphic, Volume XLVIII, Issue 5, 31 July 1912, Page 4

Curiosities of the Magnet.

The magnet can lift five and a-hal£ tons. These giant magnets used in iron and steel mills -can (says the “New York Tribune”) pick up hot as well as cold billets, and a single one of this character will displace half a hundred workmen. A further improvement may be noted in the combination of “skull-craeker” and magnet. 'Hie “skull-cracker” is a hugs pear-shaped ball of iron suspended by a chain to a hook and steel ropes. This “skull cracker” is dropped with great! force on scrap metal to be broken up for re-melting. It breaks the metal into convenient small pieces, and is lifted up and down by the magnet until the scrap is reduced to proper size. Then the invisible fingers of the magnet gather up the small piec-es and carry them to tha melting furnace. The entire operation is accomplished in one-hundredth of tha time formerly required by manual labour. More recently magnets have been employed in -the milling industry to pick out small particles of metal that frequently get into flour and cause explosions through friction when they come ini contact with the big rollers. -Not a particle of metal can escape the powerful magnets susjiended over the chute through which the grain passes. In mining and metallurgical work the magnet; has become an indispensable labour-sav-ing agent. The magnetic separation of ores has saved thousands of dollars -toj mining companies. When the roeks are erushed and p ilverised powerful magnete gather up the infinitesimal parts of metal released from their beds and convey them to the smelting furnace. Quantities of ore can thus be saved from old tailings that were formerly considered pure waste. Recently commercial magnets were employed for the novel purpose of raising sunken treasures. A big earge of nails was lost in twenty fathoms of water, and' the loss seemed irreparable until some enterprising genius raised them easily and cheaply -by means of % magnet suspended from a derrick by steel cablea.