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The New Zealand Railways Magazine, Volume 2, Issue 11 (March 1, 1928)

“Tablet” Protection

“Tablet” Protection.

The confidence which the electric tablet system lends to train operators is, in itself, a further aid to safe transit, for all who work the tablets know that the system does effectually accomplish its purpose, that of preventing more than one train being between any two tablet stations at the same time, and, when no train is in the section between the tablet stations, permitting of a train being started from either end. Short of double-tracking and one-way traffic, no system could provide greater security against the possibility of head-on train collisions between stations.

Another safety mechanical contrivance which is now applied to all the railway rolling-stock in this country, is the Westinghouse brake. In its adoption of this help towards life preservation, New Zealand was (and still is) ahead of many Continental countries.

The Westinghouse brake is an emanation of pure genius, and the art of it lies in the fact that power is required from the engine to lift the brakes on the vehicles composing the train, so that with any failure of this power, the brakes are automatically applied. Thus, should a train part through the couplings breaking, the resultant break in the Westinghouse pipe-connection releases the compressed air in the train pipe, and the air in the reservoirs of the braking-gear of all vehicles presses the brakes hard on. Consider the effect of applying the Westinghouse brake of a ten coach train, weighing altogether something like 500 tons. The brakes bite onto every one of the train's hundred wheels, under the powerful impetus of compressed air, and the hurtling mass of metal, travelling at a speed of 40 or 50 miles an hour, is brought up standing, in little more than its own length.

What New Zealand owes to the Westinghouse brake it would be difficult to estimate, but the general effect has been to add enormously to the safety of train travel.

Then, just in case of accident, every guard's van has its own fire-extinguisher, its ambulance box, its case of tools, and its supply of detonators. If a train fails on an unprotected section, the detonators are used on the rails some distance before and behind the breakdown, to warn any approaching train that the line ahead is blocked.

The system of interlocking railway yards has been extended to all the busy centres. Under it the signals, and the various points at the station interlocked, are so arranged that a “clear” signal cannot be given for a train to come into the yard unless all the points are properly set and interlocked for its approach. The responsibility still rests upon a signalman to see that the track for the approaching train is clear, but having done that, the fact that the signal can be pulled to “clear” is a definite assurance that all the relative points are properly “set.”

Then, at stations where standard mechanical or electrical interlocking has not yet been found necessary, a species of simplified interlocking has been achieved under the “Woods locks” system. Prior to its introduction, the question which every stationmaster at a wayside station had to keep in mind, before signalling in a train, was “are the main line points locked”? There was no absolute check on this, and the only safe course was to go and see; a task which meant, in some cases, wearing out boot leather over the rough ballast in a walk of several hundred yards, the possible waste of time just before a train was due, and also waste of energy if the points were found to be—as they should be,—properly locked. The key of the Woods lock, however, cannot be removed from the main line points unless they are locked, and, as the same key is required to manipulate the semaphore to signal the train in, it is obvious that if the key is available for the signal, the points must be locked.

The latest phase of signalling development is the automatic, under which automatic signals are track-circuited in such a way that the position of the signal is regulated by the trains passing over the section of track to which it relates. By the position (or colour) of the signal, the driver knows whether he may go full speed ahead (that's the green), slow down to keep his page 8 distance from another train (that's the orange), or stop on account of the track being blocked (that's the red).

Distant control of main line points is now being introduced at various way-stations, the points being motor-worked, the control operating, if required—and with perfect safety—up to a distance of over half-a-mile from the signal cabin.

The condition of the track and the speed of trains are two other facts upon which safety in transit depends. That the tracks in New Zealand are kept in excellent order is recognised; but it is not so well known that the Fay-Raven Commission expressed the opinion that the permanent way was kept even at a higher standard than the requirements demanded. There has, however, been some publicity given to the opinions of one or two non-professional visitors from overseas, that some of the train speeds, over certain portions of the track, are too high. In reply to this I would say that train schedule speeds everywhere are limited by certain maxima applicable to each portion of the line, the grades and curves being allowed for with meticulous exactness and in strict accordance with what engineering practice the world over has proved to be within such limits as are necessary to provide an ample margin of safety. Predictions of disaster are as unfounded as those old-time ones that said a ship would sink because it was made of iron; or the sayings of later critics who have held, without the slightest pretence to engineering knowledge, and in all the valour of ignorance, that London Bridge was too weak, or the Wool-worth building too high, for safety.

There are some things that no safety system can provide against—earthquakes and cloud-bursts, and the acts of King's enemies. The possibility of human carelessness or mental aberration cannot be entirely eliminated. But, these things aside, you can see there is no danger in travel by train under the conditions provided by the Railway Department in this country.

It is natural, in a talk on safety by train that the road crossing problem should be taken into account.

Photo. W. W. Stewart. Holiday Crowds Waiting On Auckland Station.

Photo. W. W. Stewart.
Holiday Crowds Waiting On Auckland Station.

Now, according to the legal theory of road use, the foot passenger has “the right of road.” But if you are walking you don't stop to enforce this right. When the motorist toots, you skip. If you are driving a car, you expect the pedestrian page 8 to skip. It is he who will be hurt if he doesn't. But when the motorist comes to a railway crossing, he must change his attitude; and it well may be that an all-pervading belief in the efficacy of a motor horn, and the inability to see that a toot won't scare a train, accounts for most of the level crossing accidents.

One should note here that it is the increased use made of the rail for travelling that has encouraged the introduction of its modern safety methods. The more the railways are used, the greater the safety by train becomes, for increased rail traffic invariably means further improvements in the safety system of our Railways.

When you make a train trip, it is like an oasis of safety in a desert of danger. I must confess, after seeing something of the inner workings of the Railway safety system, that the romance attaching to the safety it provides makes me feel almost lyrical.

Once aboard the train, the electric spark of the railway signal-towers tells that your train is on the wing. The surfaceman, the ganger, the workshops staff; the civil, the electrical and the mechanical engineer; the signalman, the station-master, the driver and the guard, have all conspired to make your journey safe.

The guardians of the metal track cry “right-of-way” for the queen of the road. Then switches click, the roads are set, and “two two nine”—the “Limited” crack—goes speeding through the night. Signals dip and swing to “clear” as the care-free passengers are borne along on the track of steel, smoothly, swiftly, safely to their journey's end.

View Of Opunake Beach, Taranaki. [Photo N.Z. Publicity Department.] A record excursion was run recently from Wanganui to Opunake, over 700 people travelling by excursion train.

View Of Opunake Beach, Taranaki.
[Photo N.Z. Publicity Department.]
A record excursion was run recently from Wanganui to Opunake, over 700 people travelling by excursion train.