The resistance coils themselves are generally wound on brass or copper bobbins, with silk-covered manganin wire, which should first be aged by heating for about ten hours to a temperature of 140° C., to remove the slight tendency to change in resistivity which would otherwise present itself.
Lucy Larcom,' born in Beverly, came to Lowell in 1835, where her widowed mother kept a " corporation " boarding-house, and where she became a " doffer," changing bobbins in the mills.
Fancy cotton goods are of great variety, and many of them have trade names that are used temporarily or occasion produced on the surface of the cloth by needles placed in a sliding frame; lustre, a light dress material with a lustrous face sometimes made with a cotton warp and woollen weft; zephyr, a light, coloured dress material usually in small patterns; bobbinnet, a machine-made fabric, originally an imitation of lace made with bobbins on a pillow.
He winds it on bobbins with a rapid reciprocating motion, so as to lay the fibre in diagonal lines.
These bobbins are then in general taken to the first spinning frame, and there the single strands receive their first twist, which rounds them, and prevents the compound fibre from splitting up and separating when, by the subsequent scouring operations, the gum is removed which presently binds them into one.