Aluminum-zinc alloy

Aluminum-zinc alloy

Ioo N o t e s and C o m m e n t s [J. F. I., lmtural mica is p r o d u c e d seem t o place its artificial manufacture o n a commercial scale b e y...

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Ioo

N o t e s and C o m m e n t s

[J. F. I.,

lmtural mica is p r o d u c e d seem t o place its artificial manufacture o n a commercial scale b e y o n d t h e range of reasonable possibility: a n d should a n y new art arise requiring t h e nse of mica o n a l a r g e scale, it would of c o u r s e give a large additional impetus to mica p r o d u c t i o n . [THE E N D . ]

TITANIFEROUS

IRON

ORE.

The blast-furnace is not suitable for the reduction of titaniferous iron ore. But in the electric furnace it is possible to obtain a final product containing a large or small percentage of titanium as desired. The adwmtage of the treatment of titaniferous iron ore, vast quantities of which exist in the U n i t e dStates, lies in the value of the by-products, particularly the'ferrotitanium and titanium earbide.--Eng, and Min. 7our.

P H I L A D E L P H I A FIRE ESCAPES. A type of fire e s c a p e h a s been developed under the Building Laws of Philadelphia primarily for use in factories, which is so remarkably efficient and so far a h e a d of safety of anything else that exists, that we may wonder why it has not been copied in o t h e r cities. I t is somewhat expensive, but the safety it gives is well w o r t h the e x t r a cost. The fundamenta! idea is that the stairway t o w e r is absolutely cut off from the various r o o m s and floors which it serves. O n e must go out from the room into the open air and then e n t e r the stairway. Once within this, he can proceed without danger to the bottom. The same idea can be applied to the fire escapes from a theatle.

ALUMINUM-ZINC

ALLOY.

A n alloy of two parts of aluminum and one part of zinc is equal to good cast iron in strength, and superior to it in elastic limit. Its color is white. I t t a k e s a fine, s m o o t h finish and does not readily oxidize. I t melts at a dull red heat, or slightly below, and is very fluid, r u n n i n g freely to the extremities of the mold and filling perfectly small o r thin p a r t s ; in that respect it is said to be superior to brass, but it is brittle, and hence unsuited to pieces which require the tougness possessed by b~ass. The tensile strength of the alloy was f o u n d to be approximately 22,000 pounds per square inch, and its specific gravity 3.3.--Eng. and Min. Jour.