Lessons in practical electricity; principles, experiments, and arithmetical problems; over four hundred illustrations; an elementary text book (1909)
Swoope, C. Walton (Coates Walton), d. 1901 · New York, D. Van Nostrand company · leaf 29
graphs 2 and 11 are called permanent mag-nets because they retain their magnetism permanently, to acertain extent, after magnetisation. Some qualities of steelwhich possess good machine tool properties are not adapted Fig. 12.—Round Bar Magnet. to making good permanent magnets. Steel containing… … Fig. 13.—Students Bar Magnet Set. permanently. Jessops steel is well adapted to making goodpermanent magnets. Select a piece of good, close-grained,rolled steel that has not been heated since it was made and cut it (about 6Xfx£orl2XlX^). Tem-per the steel glass-hardby heating it to a moder-ately…
Electricity · Magnetism
Internet Archive · Library of Congress · Public Domain Mark 1.0. Free to use for anything.
