Stone is rarely employed so as to be subject to a tensile stress. The following Table is chiefly from Mr. Stoney's work on Strains, and he remarks that it would be well to have the figures corroborated.

Material.

Tearing

Weight per

Square Inch in lbs.

Authority.

Arbroath paving ....

1261

Buchanan.

Caithness do. ....

1054

Do.

Chilmark.....

500

Do.

Craigleith stone ....

453

Do.

Hailes......

336

Do.

Humbie ......

283

Do.

Binnie ......

279

Do.

Whinstone .....

1469

Do.

Marble, white .....

722

Hopkinson

Do. .....

551

Do.

Slate ......

9600 to 12,880

Rankine.