10. Q.-What do you understand by main-reservoir pressure, and where does it begin and end?

A. It means the pressure of the air in the main reservoir, and begins at the discharge valves of the air pump and ends at the rotary valve of the brake valve.

11. Q.-State what the standard brakepipe pressure is on this railroad that is carried on freight trains. On passenger trains.

A. The candidate will here name the standard brake-pipe pressures carried on his road.

12. Q.-Name the standard main-reservoir pressure on this railroad for both freight and passenger trains.

A. The candidate will here name the standard main-reservoir pressure carried on his road.

13. Q.-What is meant by an automatic brake, and how is it operated?

A. It is a brake system in which the necessary braking power is stored in the auxiliary reservoir under each car, engine or tender for use on the particular car or engine. The brake is operated by changing the pressure of the air in the brake pipe; thus if a hose or pipe were to burst or the train were to part, the triple valves would automatically apply the brakes on the whole train, thus insuring an automatic safety device which could not be had if the train were equipped with a straight-air brake.

14. Q.-How would you apply and release an automatic brake?

A. The automatic brake is applied by reducing the pressure of the air in the brake pipe below that in the auxiliary reservoir, and is released by increasing the pressure of the air in the brake pipe above that in the auxiliary or by reducing the pressure in the auxiliary below that in the brake pipe, as is the case when bleeding off a brake.

15. Q.-What are the different positions of the brake valve and when are they used?

A. The different positions of the G-6 brake valve are: Full release position, and is used in releasing the brakes and in charging the equalizing reservoir, brake pipe and auxiliary reservoirs. Running position, which is used while the brakes are off, as when running along the road. The brake-valve handle must be in running position in order to have excess pressure. Lap position, all ports are closed and the air is prevented from pass

ing through the valve; this position is used between reductions during a service application. Service position, which is used when applying the brakes during a service or gradual application. Emergency position, which is used when it is desired to stop the train in the shortest possible time, as in cases of danger to life or property.

16. Q. How should an air pump be started? Why?

A. The air-pump lubricator should be started as soon as the pump, and the pump started slowly at first with the drain cocks open so as to allow the water of condensation to escape gradually and to prevent pounding. When the pump is working against pressure the air in the air cylinder acts as a cushion for the pistons; when the pump is first started there is little or no air in the main reservoir to prevent the pistons from striking the cylinder heads violently if steam is turned onto the pump through a wide open throttle; therefore the pump should be run slowly until about 25 or 30 pounds pressure has accumulated in the main reservoir so as to cushion the pistons, when the speed can be increased.

17. Q.-Is there more than one size of air pump in use on this railroad? Name them, giving the size of each.

A. The candidate will here name the different size air pumps used on his road and give the size of each. The 9-inch pump has cylinders 93-inch bore and 10inch stroke; the 11-inch pump has cylinders 11-inch bore and 12-inch stroke.

18. Q.-What is the necessity for more than one size of air pump?

A. To conform to the requirements of the different classes of service and to meet the demand for a pump of greater capacity.

The Block Signal and Train Control Board.*

During the past year the board has examined the plans and specifications of 308 devices, and has transmitted to the proprietor in each case a complete statement of its opinion regarding the merit and practicability of the device. Summing up, plans and specifications of 937

*Extracts from third annual report of the Block Signal and Train Control Board to the Interstate Commerce Commission, dated November 22, 1910.

different devices and forty-eight modifications or revisions of plans originally presented have been submitted for the board's consideration. Of this number, 819 have been disposed of, leaving 166 cases now before the board for consideration. The great majority of these 166 cases are now in process of examination, but there are a considerable number in which complete information has not yet been furnished by the proprietors. The board has also received a mass of correspondence relating to devices concerning which no plans have been furnished. In many cases inventors, mistaking the functions of the board, have presented ideas looking to the development of some form of safety device and have requested the assistance of the board in embodying their ideas in a device that would perform the function intended in a practicable way. In all such cases the inventors have been informed that their ideas cannot be considered unless presented in the form of plans and specifications showing in detail a practicable device designed to perform a useful function and clearly describing the manner in which that function is proposed to be performed. The board has always endeavored to assist inventors by pointing out defects in apparatus and offering suggestions for improvement, but it cannot undertake to perform the functions of a consulting engineer.

Of the plans examined during the past year 91 covered signal and automatic train-control devices, 103 related to ties, rails, rail fastenings, switches, and other track appliances, 64 were devices relating to the construction and equipment of cars and locomotives, such as couplers, draft rigging, ash pans, headlights, etc., 30 related to adjuncts of the air brake system and emergency brakes for cars, 9 were mail-bag catching and delivering devices, 7 were automatic hose connectors, and 4 were torpedo placers.

Miscellaneous Devices.

Outside the field of signaling and automatic train-control the board has considered comparatively few devices that were believed to possess merit warranting special commendation or special action on the part of the board. While many of the inventions examined-particularly those relating to track-possess meritorious features, few, if any, have thus far been examined which would, in the opinion of the board, promote the safety of railway op

eration to any greater degree than similar devices now in common use.

Connectors.--Two automatic hose connectors have been held to possess merit warranting the conduct of practical tests under service conditions, and the board is informed that the proprietor of one of these devices is now endeavoring to procure the necessary equipment for test purposes. As noted in the board's last annual report, automatic hose connectors are now used regularly, but only to a limited extent, and their use still seems to be regarded as experimental. Some of the hose connectors that have been presented to the board for examination possess theoretically good features which would seem to render devices possessing them entirely practicable. One of the main reasons for failure of the railroads to adopt hose connectors, so far as the board can determine, seems to be the failure of manufacturers and designers of connectors to agree upon the specific form of connector contour that will fulfill the requirements of the situation. . . .

Brakes. In the field of train brakes no important development has taken place during the year. As previously stated, thirty devices of this character have been examined, but most of these were of such character that their use would introduce complications into the brake system as a whole and destroy its flexibility to such an extent that, even though their intended functions might be satisfactorily performed, their use would probably reduce the efficiency of the brake system as a whole and no increase in safety would be attained.

Two complete brake systems have been presented. One of these, that of the St. Clair Air Brake Company, of Indianapolis, Ind., was treated in the board's second annual report. So far as the board is informed, there have been no new developments in that system during the past year.

The other brake system is that of the California Valve and Air Brake Company, of Los Angeles, Cal. The distinctive feature of this device is that it retains all the advantages of the straight air brake and at the same time permits automatic application of the brakes. The disadvantage of being compelled to release, and thus lose braking power, while recharging the auxiliary reservoirs, as is necessary with systems now in use, is overcome, and the use of pressure-retain

ed by the fact that the high power of the light serves to reveal at a considerable distance the position of the signal arm. The usual rules governing enginemen in their interpretation of signal indications state that the indications will be displayed by day by positions of the semaphore arm, and in addition at night by lights of prescribed color, the effort being made to train the enginemen in so far as possible to depend upon position rather than upon color.

In the case of classification signalsthat is, the colored lamps used on the front end of engines to indicate whether the train is an extra rather than a regular train, or whether it is running in two or more sections-the condition is much more liable to cause a misunderstanding of signals for the reason that classification signals are color signals purely, and are not signals of position. So difficult is it to read classification signals correctly when viewed in the beam of an electric headlight that railroads have made strenuous objection to their use on this account alone.

The whole question at the present time is in a highly controversial state. So far as opinion has at all crystallized, it appears to be as follows:

On single-track roads, particularly those in mountainous country or where fixed signals are infrequent, the highpower headlight on a train affords a warning of its approach for a considerable distance, and under favorable circumstances it enables the engineman to distinguish obstructions or unusual objects on the track much farther ahead than is possible with ordinary lights.

On double-track roads, and particularly on roads having three or four tracks and equipped with signals placed at frequent intervals, the prevailing opinion seems to be that the electric headlight is not only unnecessary, but is likely to cause serious errors on the part of enginemen in reading color signal lights.

Metal, Concrete, and Composite Ties. Various forms of ties composed of material other than wood and designed to improve the condition of railway track, both with respect to economy and to safety of train operation, have been submitted to the board for examination. Important economic questions enter into the consideration of this subject. By the use of wooden ties placed in a roadbed properly ballasted and drained, and with ade

quate track fastenings, a safe track can be maintained. The main advantage, therefore, to be derived from the use of ties of material other than wood is decreased cost of maintenance and renewal. In the employment of electric track circuits in railway signaling it is necessary to insulate one rail from the other. An important difficulty with the metal tie is found in the problem of providing proper insulation. Another important matter in connection with the use of both metal and concrete ties is the difficulty of maintaining proper gauge and surface under varying climatic conditions. In the winter season, in sections where there is considerable moisture in the ground, freezing causes the roadbed and track to heave, distorting the surface. In common practice this condition is met by blocking up or shimming the rails, or in some cases where short sections of track heave in winter, blocking is used between ties and rails in summer and removed gradually in winter as the ties heave. Metal or concrete ties cannot be adzed to diminish their thickness nor can holes for bolts or spikes be bored in them at random for altering the relation of the rail, to the tie so as to maintain proper gauge and surface. This is a problem which must be solved by the design of proper track fastenings. It is believed that the development of efficient devices of this character will hasten the development and more extensive use of metal and concrete ties. Up to the present time the development of concrete ties has not progressed as far as that of metal ties; this is believed to be due largely to the fact that much of the effort in concrete tie construction was made prior to the comparatively recent development of concrete composition, manipulation, and reinforcement. It is probable, however, that when it becomes necessary to use other materials than wood, both metal and concrete will find large fields of usefulness in railway the construction.

As a number of the ties which have been submitted to the board for examination are now in service, and have been used for a sufficient length of time to disclose their good and bad features and permit the formation of fairly accurate conclusions regarding their practicability, from the standpoints both of safety and of economy, the board appointed a committee, consisting of Chairman Cooley and Mr. Ewald, to make a personal ex