“When a train is ready to move from A to X the operator at A presses down the lever which is seen at the bottom of the right-hand dial, sounding one bell at X, which is for the purpose of calling the attention of the operator at X to the fact that A desires to send a train forward. The operator at X acknowledges the call by pressing the lever on his instrument, sounding a bell in the tower at A. The operator at A then asks permission from X to withdraw staff by pressing down the lever before mentioned three times, giving three rings on the bell at X, and immediately turns his right-hand pointer to the left, leaving it in the horizontal position pointing to the words ‘For staff,’ indicating that he desires operator at X to release his instrument so that he can take a staff or train order from it. If there is no train or any portion of a train between A and X, the holding down of the lever at X closes the circuit in the lock magnets at A, which enables the operator at A to withdraw a staff. As soon as this staff is removed from A, A turns the left-hand pointer to the words ‘Staff out,’ and in removing this staff from the instrument A the galvanometer needle which is seen in the centre of the instrument between the two dials vibrates, indicating to the operator at X that A has withdrawn his staff. X then releases the lever which he has held down in order that A might withdraw a staff and turns his left-hand indicator to ‘Staff out,’ and with this position of the instrument a staff cannot be withdrawn from either one.

“The first method of delivering this staff to the engineer as a train order was to place it in a staff-crane, which crane was located on the platform outside of the block station. With the staff in this position it has been found in actual practice that the engineman can pick it up while his train is running at a speed of 30 miles per hour. A second staff cannot be removed from A nor a staff removed from X until this staff which was taken by the engineman in going from A to X is placed in the staff instrument at X; consequently the delivering of a staff from A to the engineman gives him absolute control of the section between A and X.

“This train order staff also controls all switches leading from the main line between A and X, for with the style of switch-stand which we have designed for the purpose the trainman cannot open the switch until he has secured the staff from the engineman and inserted it in the switch-stand, and as soon as he throws the switch-lever and opens the switch he fastens the train-staff in the switch-stand, and it cannot be removed until the switchman has closed and locked the switch for the main line. When this is done he may remove the train-staff and return it to the engineman. It will thus be seen that this train order, in the shape of a staff, gives the engineman absolute control over the section, and also insures that all switches from the main line are set properly before he can deliver the train-staff to the instrument at X.

“In order that the operator at X may be assured that the entire train has passed his station, we may divide the staff in two and deliver one half to the engineman and the other half to the trainman on the caboose or rear end of the train, and it will be necessary for the operator at X to have the two halves so that he may complete the staff in order to insert it into the staff instrument at X, as it is impossible to insert a portion of the staff; it must be entirely complete before it can be returned to the staff instrument.”

Instead of using the entire staff as a whole or in two parts, Mr. Hansel suggests that one or more rings on the body of the staff be removed from the latter and given to the engineman or other trainman to be placed upon a corresponding staff at the extreme end of the section. This would answer the purpose, for no staff can be inserted in a machine unless all the rings are in their proper positions. These rings can be taken up by a train moving at any speed from a suitable crane at any point alongside the track.

For a rapid movement of trains on a single-track railroad under this staff system an engineman must know before he approaches the end of the section whether the staff is ready for delivery to him. In order to accomplish that purpose the usual distant and home signals may readily be employed. The distant signal would show him what to expect, so that he would approach the entrance to the section either at full speed or with his train under control according to the indication. Similarly, electric circuits may be employed in connection with the staff or rings in the control of signals which it may be desired to employ.

The electric train-staff may also be used in a permissive block system, the section of the track between stations A and X constituting the block. In Fig. 19, showing the machine, a horizontal arm is seen to extend across its face and to the right. This is the permissive attachment which must be operated by the special staff shown on the left half of the machine about midway of its height. If it is desired to run two or three trains or two or three sections of the same train from A before admitting a train at X in the opposite direction, the operator at A so advises the operator at X. The latter then permits A to remove the special staff with which the extreme right-hand end of the permissive attachment is unlocked and a tablet taken out. This tablet is equivalent to a train order and is given to the train immediately starting from A. A second tablet is given in a similar manner to the second section or train, and a third to the third section. The last section of train or train itself starting from A takes all the remaining tablets and the special staff for insertion in the machine at X. In this manner head-to-head collisions are prevented when a number of trains are passing through the block in the same direction before the entrance of a train in the opposite direction. This system has been found to work satisfactorily where it has been used in this country, although its use has been quite limited. Evidently, in itself, it is not sufficient to prevent rear-end collisions in a block between trains moving in the same direction. In order to avoid such collisions where a train falls behind its schedule time or for any reason is stopped in a block, prompt use must be made of rear flagmen or other means to stop or to control the movement of the first following train.

The most improved form of high-speed train-staff machine is shown in Fig. 20, as made and installed by the Union Switch and Signal Company and used by a number of the largest railroad systems of the United States. In these machines the staffs are but a few ounces in weight.