Improvements in or relating to the Testing of Iron Materials

116,162. Pozzo, A., and Colonnetti, G. June 8, 1917. Addition to 107,376. Magnetic tests and measurements. - Apparatus for comparing the permeability of a specimen of iron with that of a standard, as described in the parent Specification, includes additional means for detecting or integrating changes due to the action of external mechanical forces or variations in different parts of a long specimen. As shown, the additional indicator i, such as an integrating galvanometer, a telephone or relay, is connected to a separate secondary s; the main indicator V connected to the opposed secondaries II, II is controlled by a switch t. The indicator i may, however, be connected to the secondary II, or a separate primary may be provided. The apparatus may be used for determining the re-hardening or deformation under tension, pressure, bending, or torsion of test-pieces; or it may be used in testing hollow bodies, such as projectiles under hydraulic pressure, or of girders, axles, &c. under direct loading.