Birmingham Wire Gauge.

Weight per foot superficial in ounces.

Weight per sheet, 4 feet by 2 feet, in lbs.

20

26

13

22

20

10

24

16

8

Birmingham Wire Gauge.

Weight per foot superficial in ounces.

Weight per sheet, 4 feet by 2 feet, in lbs.

26

12

6

28

8

4

30

6

3

Sheet copper, weighing from 12 to 20 oz. per square foot, is used for roofs, flats, and gutters. Copper wire from 17 to 19 B.W. gauge for bell-hanging.

When used for roofing, copper is laid in a way somewhat similar to zinc (see p. 269, Part II.)

Copper Wire Cord

The following are the working loads 2 for the different sizes : -

Circumference in inches

11/4,

11/8,

1,

3/4

5/8

1/2,

3/8,

1/4

Working load in lbs.

448,

336,

224,

168,

112,

75,

50,

34.

Copper Wire-covered Steel Ribbon Sash Line is also made under Hookham's patent in three sizes, having a breaking strain in cwt. as follows : -

No. 1

2

3

3 cwt.

41/2 cwt.

7 cwt.

1 Verdigris, properly so called, is a basic acetate of copper. 2 Sheffield Standard List.