Signals may be dispensed with on single lines under the following conditions:—
(a) At all stations and siding connections upon a line
worked by one engine only (or two engines coupled together), carrying a staff, and when all points are locked by such staff.
(b) At any intermediate siding connection upon a line worked under the train staff and ticket system, or under the electric staff or tablet system, where the points are locked by the staff or tablet.
(c) At intermediate stations, which are not staff or tablet stations, upon a line worked under the electric staff or tablet system: Sidings, if any, being locked as in (b).
3. The signals at junctions to be on separate posts, or on brackets; and the signals at stations, when there is more than one arm on one side of a post, to be made to apply—the first, or upper arm, to the line on the left, the second arm to the line next in order from the left, and so on; but in cases where the main, or more important line, is not the one on the left, separate signal-posts to be provided, or the arms to be on brackets. Distant-signals to be distinguished by notches cut out of the ends of the arms, and to be controlled by home or starting signals for the same direction when on the same post. A distant-signal arm must not be placed above a home or starting signal arm on the same post for trains going in the same direction.
In the case of sidings, a low short arm and a small signal light, distinguishable from the arms or lights for the passenger lines, may be employed, but in such cases disc signals are, as a rule, preferable.
Every signal arm to be so weighted as to fly to and remain at danger on the breaking at any point of the connection between the arm and the lever working it.
4. On new lines worked independently, the front signal lights to be green for “all right,” and red for “danger;” the back lights (visible only when the signals are at “danger”) to be white.
This requirement not to be obligatory in the case of new lines run over by trains of other companies using a different system of lights.