D—2.

SIGNAL AND ELECTRICAL BRANCH. The following is a summary of the principal activities of the Signal and Electrical Branch during the year: — Signalling. Stratford. —The alterations to signalling equipment for working the reversing triangle in connection with the opening of the Branch to Okahukura has been installed as completion of the track work has allowed. This installation includes power-operated points and signals. Okahukura.—A new system of key locking and signalling was well in hand at the close of the year. General. —Alterations and additions to existing signalling and interlocking have been carried out at Avondale, Remuera, Petone, and Sheffield. Home signals with Woods locks have been removed from Onehunga Wharf and Fairdown and starting-signals from Edendale. Main-line distant signals have been installed at Edendale, and a repeater light signal at Puketeraki. Tablet locks interlocking siding-points with the tablet system have been installed at Kakahi Station and at a number of private and service sidings. Prame levers were installed at nine stations during the year and opportunity was taken, where renewal of existing gear was necessary, to improve the design of locking on the main-line points in these cases. The total number of signalling installations is as follows : — Miles of single-line automatic signalling .. .. . . .. 190 m. 41 ch. Miles of double-line automatic signalling .. .. 63 m. 14 ch. Automatic crossing-loops .. .. .. .. . . 33 Automatic switch-locked sidings . . .. .. .. . . 34 Power interlockings .. . . .. .. .. 27 Mechanical interlockings . . .. .. . . . . .. 100 Interlocked tramway-crossings .. .. . . .. 7 Mechanical fixed signal and Wood's locked stations .. . . 306 Tablet locked sidings .. .. . . .. .. . . 265 Telegraph and Telephone Facilities. Block-working.—During the year Onehunga - Onehunga Wharf, and Longburn-Poxton tablet sections have been closed. Onehunga Wharf, Foxton, Himitangi, Rangiotu, Tarukenga, and Fairdown have been closed as tablet stations. Arahiwi, Ngongotaha, and Southbrook have been converted from ordinary to switch-out tablet stations, Southbrook embodying special features in design, being switched out over an adjacent switch-out section. A bank engine key was installed at Paeroa. The present position in regard to block working is as follows : — Total mileage equipped with tablet instruments.. .. .. .. 1,577 Number of tablet instruments in use . . . - . . .. 847 Number of tablet stations . . . . .. , . - 354 Number of tablet exchangers .. . . . . -. .. 314 Mileage of double line worked by lock and block . . .. . . 15 Number of stations . . .. . . . . , . . . .. 13 Number of instruments .. .. . - 26 The third year of the communications rebuilding programme has resulted in long-distance telephone communications being possible over a large proportion of the railway networks of both Islands. Two hundred and eighteen miles of pole-line was rebuilt in the North Island and 60 miles in the South Island. On these pole-lines the worn-out iron circuits were replaced with copper conductors and new circuits run to give the required extra facilities. In addition to renewing 864 miles of old iron wire with copper conductors, 866 miles of copper wire for new circuits have been erected. The sections rebuilt include : Auckland-Helensville, Frankton Junction - Morrinsville, OhakunePorootarao, Palmerston North - Marton, Palmerston North - Takapau, and Rolleston-Rangitata. A train-control system from Frankton Junction to Ohakune was completed so that all trains on the main line from Auckland to Wellington now run under train control, with control stations at Auckland, Ohakune, and Wellington. From Napier to Palmerston North and from Christchurch to Invercargill intercall telephone systems of the most modern pattern have been completed, giving a flexibility in service hitherto unobtainable. A larger exchange with voice frequency repeater for use with intercall lines has been installed at Dunedin, and the small exchange removed to Timaru. A greater use of circuits by the formation of phantom circuits and carrier-frequency telephone systems has been evolved, and practically all long-distance circuits are now arranged with other services superimposed upon them. The cable for the Paekakariki-Wellington Section of the Main Line is now to hand, and its installation is being proceeded with, although its completion will be delayed until the new Tawa Flat route is made available by Public Works Department.

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