Henley's Twentieth Century Formulas, Recipes and Processes. Various

Composition Files.—

	I	II
Copper	64.4	62
Tin	18.0	20
Zinc	10.0	10
Lead	7.6	8

      Vogel’s Composition Files.—

	III	IV	V
Copper	57.0	61.5	73.0
Tin	28.5	31.0	19.0
Zinc	78.0	—	8.0
Lead	7.0	8.5	8.0

      VI.—Another alloy for composition files is copper, 8 parts; tin, 2; zinc, 1, and lead, 1—fused under a cover of borax.

      Easily Fusible Or Plastic Alloys.

      (These have a fusing point usually below 300° F.)

      (See also Solders.)

      I. Rose’s Alloy.—Bismuth, 2 parts; lead, 1 part; tin, 1 part. Melting point, 200° F.

      II. Darcet Alloy.—This is composed of 8 parts of bismuth, 5 of lead, and 3 of tin. It melts at 176° F. To impart greater fusibility, ¹/₁₆ part of mercury is added; the fusing is then lowered to 149° F.

      III.—Newton alloy melts at 212° F., and is composed of 5 parts of bismuth, 2 of lead, and 3 of tin.

      IV.—Wood’s Metal.—

Tin	2 parts
Lead	4 parts
Bismuth	5 to 8 parts

      This silvery, fine-grained alloy fuses between 151° and 162° F., and is excellently adapted to soldering.

      V.—Bismuth, 7 parts; lead, 6 parts; cadmium, 1 part. Melting point, 180° F.

      VI.—Bismuth, 7 to 8 parts; lead, 4; tin, 2; cadmium, 1 to 2. Melting point, 149° to 160° F.

      Other Easily Fusible Alloys:

	VII	VIII	IX
Lead	1	2	3
Tin	1	2	3
Bismuth	1	1	1
Melting Point	258° F.	283°	311°

      Fusible Alloys For Electric Installations.

      —These alloys are employed in electric installations as current interrupters. Serving as conductors on a short length of circuit, they melt as soon as the current becomes too strong. Following is the composition of some of these alloys.

	Fus­ing temp­er­a­ture	Lead	Tin	Bis­muth	Cad­mi­um
I	203° F.	250	500	500	—
II	193° F.	397	—	532	71
III	168° F.	344	94	500	62
IV	153° F.	260	148	522	70
V	150° F.	249	142	501	108
VI	145° F.	267	136	500	100

      {65}

      These alloys are prepared by melting the lead in a stearine bath and adding successively, and during the cooling, first, the cadmium; second, the bismuth; third, the tin. It is absolutely necessary to proceed in this manner, since these metals fuse at temperatures ranging from 850° F. (for lead), to 551° F. (for tin).

      Fusible Safety Alloys for Steam Boilers.—

	Bismuth	Lead	Zinc	Melt­ing point	At­mos. pres­sure
I.	8	5	3	212° F.	1
II.	8	8	4	235° F.	1.5
III.	8	8	3	253° F.	2
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