The following figures indicate the crushing load for bricks of various types in tons per sq. in.: -

Common hand-made

from

0.4

to

0.9

" machine-made

"

0.9

"

1.2

London stock

"

0.7

"

1.3

Staffordshire blue

"

2.8

"

3.3

Sand-lime

"

2.9

"

3.4

See also Brickwork.

(J. B.*; W. B.*)

[1] The term "marl" has been wrongly applied to many fire-clays. It should be restricted to natural mixtures of clay and chalk such as those of the Paris and London basins.