THE SOUTH POLE.

New Zealand Herald, Volume XLIII, Issue 13134, 24 March 1906, Page 4 (Supplement)

THE SOUTH POLE.

"'Experts have lately come to the conclusion that the South Pole will be reached long before its rival in the North, and this in spite of the much greatei number of expeditions in search of the latter. They base their reasoning on the hypothesis that the belt of ice is really a remnant of the old glacal period, and that it is rapidly melting away. The 'formation in the Antarctic region is quite different from that in the Arctic. Instead, of icefields (properly socalled) there is an almost continuous and unbroken high belt. This belt has retreated inward 30 miles during the last 50 years. When the whole is melted, it is thought that it will be impossible for it to be frozen into the same formation again. It will simply become subject to the operation ■which cold has on salt water during the winter months. It is further believed that a.!-vast tract of land lies there which will become not only habitable but of some importance commercially.

AUTOMATIC RAILWAY SIGNALLING. p It is announced that an improved train service on the District Railway (London) | cannot bo brought into operation until tjie | automatic signals are in use. The whole of the' district has been equipped, and the signals have been working for some lime except "through the tunnels," i.e., from South -Kensington to the Mansion House. The principle of automatic signals is fairly -.veil known now. Instead of the signal arms ' being lowered raid raised through the operation of levers by a signalman in a signalbox who acts in accordance with telegraphic advices on the block instruments, the signals are lowered and raised by the movement of the trains. The signals are operated by powerair, gas, or electric motor— and the supply is controlled by relays inserted in the running rails, which are banded together into sections. It is thereby so arranged that in the event of a train, or any part of a train, standing in the section, the electrical current controlling the power for operating the signal is short circuited by the train, so that L.e signal for entering the section where the obstruction exists cannot be lowered. If the section be clear tho releasing current flows freely, and the signal is lowered. Immediately a train passes ft signal the holding mechanism on the .signal is freed, and' the arm goes to danger behind the train, and it cannot again be lowered until the whole of the preceding train has passed out of the section, when it will fall to —under "normal clear" conditions it may remain at danger until required to be lowered by an approaching train under " normal danger" conditions. Such a method of working is ideal for such services as those on the underground railways of .London, where no shunting operations have to be performed, as by the trains Signalling themselves the need for signalmen and signal-boxes is removed. The City &nd South London and the Central London arc signalled 'by the older method of signalboxes. signals, and block instruments, but the Great Northern and City and the Baker-street and Waterloo are protected by automatic signals. Lugineei. ,