The specific gravity of a solid or liquid body is the ratio between its weight and that of a like volume of distilled water. If the solid is of irregular shape, its specific gravity may be found by weighing it in air and in water; the loss of weight in water is the weight of an equal volume of water; hence, if W is the weight in air, and W' the weight in water, the specific gravity is W divided by (W-W')

The weight of water in various conditions is as follows:

Water, pure at 32° F. weighs 62.417 lb. per cu. ft.

Water, pure at 39° F. weighs 62.425 lb. per cu. ft.

Water, pure at 62° F. weighs 62.355 lb. per cu. ft.

Water, pure at 212° F. weighs 59.700 lb. per cu. ft.

Water, sea...................weighs 64.080 lb. per cu. ft.

Ice ............................weighs 57.400 lb. per cu. ft.

Snow, fresh................weighs 5 to 12 lb. per cu. ft.

Snow, wet...................weighs 15 to50 lb. per cu. ft.

Metals

Name of Metal.

Weight perCu. In.

Pounds.

Weight per Cu. Ft.

Pounds.

Specific Gravity.

Aluminum......................

.096

166

2.66

Antimony.......................

.242

418

6.70

Bismuth.........................

.350

607

9.74

Brass, cast......................

.292

504

8.10

Brass, rolled...................

.303

524

8.40

Bronze (gun metal) ......

.305

529

8.50

Copper, cast...................

.314

542

8.70

Copper, rolled.................

.321

555

8.90

Gold, 24 carat ................

.694

1,204

19.26

Iron, cast ......................

.260

450

7.21

Iron, wrought................

.277

480

7.66

Lead, commercial..........

.410

710

11.38

Mercury, 60° F..............

.489

846

13.58

Platinum ......................

.779

1,342

21.50

Silver ............................

.378

655

10.50

Steel................................

.283

490

7.85

Tin, cast.........................

.265

459

7.35

Zinc..............................

.253

437

7.00