Size.

Thickness.

Proportion of Thickness to Width.

Proportion of Length to Width.

Break'g weight

Tons per sq. in.

of Section.

4 in. X 4 in.

•03

1/133

80 to 1

4.9

"

•06

1/66

"

8.6

"

1

1/40

"

10.

"

•2

1/20

"

12.

8 in. X 8 in.

•06

1/133

15 to l

6.

"

•14

1/60

"

9.

"

•22

1/36

"

11.5

"

•25

1/32

ii

12.

Column 8 feet O inches long.

18 X 18

•5

1/30 practically

5.4 to 1

13.6

Column lO feet O inches long, with cells.

8 in. X 8 in.

•06

1/66 of width of cells

16 to 1

8.6