. American telephone practice . ^r FIG. 134.—KELLOGG HOOK SWITCH. adapted to meet the requirements of almost any circuit, it beingvery easy to add more springs or to so arrange them that theircontacts will be made and broken in a definite order upon the raisingor lowering of the


Size: 2923px × 855px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: ., boo, bookcentury1900, bookdecade1900, bookidamericantelepho00mill