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recently been fitted. It is a metallic circuit, double-cord, parallel- 

 jack multiple, with self-restoring drops of a new design. With 

 the exception of these drops, which are manufactured by Ericsson 

 & Co., the whole table was made in the workshops of the 

 General Telephone Company. The self- restoring drop is shown 

 in fig. 115. The signalling magnet M I is placed in front of the 

 restoring one M 2 (see also fig. 117). The armature is a bent lever 

 L 1 pivoted at /, which, when unattracted, engages with and 

 holds up the shutter s working on the pivot pi. On dropping the 

 shutter, its base B strikes against a pin which runs in a guide the 

 whole length of the magnets and terminates at the back in a 

 shoulder Y and a pointed head z ; forces the pin back, and closes 

 the contacts c 1 c 2 of the night-bell and 'attention' indicator circuit. 

 On operating the restoring magnet M 2 , the armature L 2 is attracted, 

 and its point, striking against the shoulder Y, forces back the pin, 



which in its turn lifts the shutter s to its position of rest. At the 

 back of the drop will be seen another pair of contacts c 3 c 4 and 

 an ivory pin I attached to the armature L 2 . While L 2 remains 

 attracted under the influence of the restoring, which is also the 

 test, battery (three Tudor accumulators of 175 amp hours), the 

 pin i presses the contacts c 3 c 4 apart and breaks the circuit of the 

 M 1 coils, thus cutting out the signalling indicators during con- 

 nection, and leaving only the ring-off drop in derivation across 

 the loop. The ring-off drops are also automatically restored, but 

 mechanically. Fig. 116 shows the arrangement. L is a lever 

 pivoted at /, which, when unrestrained by the weight of the plug 

 p or pressure on the finger stud A, allows the plunger D to fall. 

 The plunger presses against a spring c placed under the electro- 

 magnet M. The shutter s is provided with a curved base piece B, 

 which, on the shutter falling, depresses the spring and closes the 

 circuit of the night-bell and ' attention ' indicator. The restora- 



