American telephone practice (1905) (14754060944)

Identifier: americantelepho00mill (find matches)
Title: American telephone practice
Year: 1905 (1900s)
Authors: Miller, Kempster B. (from old catalog)
Subjects:
Publisher:
Contributing Library: The Library of Congress
Digitizing Sponsor: The Library of Congress



Text Appearing Before Image:
677
Text Appearing After Image:
678 CENTRAL OFFICE EQUIPMENTS. 679 thus reducing still more the fire risk. In order to prevent the emptyducts from forming flues in case of fire, all unused ducts are pluggedat both ends. The main distributing frame cannot be seen in Fig. 488, as it isbehind the stairways in that figure. Its position, however, is wellshown in the plan of 489. As will be seen from this floor plan theintermediate distributing frame is arranged at the end of the mainframe; and the relay rack for the subscribers lines runs alongsideof the intermediate frame. The trunk relay and repeating coil rack