Testing Machines.

There are many varieties of tensile testing machines in use, [unclear: of] which detailed description is unnecessary. Our experience of Adie's machine is that it is thoroughly reliable.

Any machine that will admit of a regular and even strain being applied without torsion or vibration should give reliable results.

Briquettes of 2¼ inches (1½″ x 1½″ smallest section) were formerly used, but at the present time briquettes 1″ x 1″ section are in general use, as it is found that more reliable results are obtained without the expert manipulation so essential with the larger section.

The rate at which the strain is applied will affect the result—100lbs in 10 seconds is the slowest speed that should be adopted.