cylinder for each full-on application. Now, with the High Speed brake you can get that 50 pounds in the brake cylinder with a 20-pound reduction and still have 90 pounds in the auxiliary reservoir; the brake may then be released and, without waiting to attempt any recharge of the auxiliary reservoirs whatever, you can make a second 20-pound application and again secure 50 pounds in the brake cylinder, and you yet have 70 pounds in the auxiliary reservoir-enough, if you should again release the brake, to make a third application with as much power as is obtained at a full service application of the common quick-action brake. This is a feature of most desirable importance where repeated applications and releases rapidly made are necessary, or in hill braking.

Now, if you trainmen have gained a correct understanding of the High Speed brake, you will realize how very simple it is and you will not make the mistakes again that several of you have made of late. When any passenger-equipment car has had a defectively working air-brake and the defect was not clearly understood, it has been a common thing for the conductor and brakeman to imagine that the High Speed brake was in some mysterious way responsible for the trouble; indeed, such has been reported on two or three occasions when there could have been nothing the matter with the High Speed equipment on any of our cars that could have caused a brake to stick, or wheels to slide, etc.; and you can see that as we have not yet raised our brake-pipe pressure above 70 pounds we have not got the High Speed brake on any of our cars, if we have got some of the mechanical attachments that belong to it. The cars have the reducing valve, but all that those valves can do at this time is to pop off any pressure above 50 pounds that may happen to get into the brake cylinder, and that will not happen unless the engineer is carrying too high a brake-pipe pressure, or the conductor is running too short a piston travel on the car; so, the High Speed reducing valve can only be of good service to you, and I will tell you this which you should know for your own protection in case of accident and the placing of blame therefor: in case you have overlooked a partially wound-up hand brake which has over-shortened the piston travel, the reducing valve will prevent the attainment of overpressure in the brake cylinder and the wheels will

not skid from that cause-nor from too high an initial pressure from any other cause; of course, the same thing holds good when we finally come to actually operate the High Speed brake, and then, if the piston travel is too long the brakecylinder pressure will not be weakened any at a full service application, although the brake will not hold as strongly as it should at graduated application.

And, in making statements or reports concerning certain accidents don't mislead yourselves into asserting that "engineer had released the brakes," just because you heard the familiar whistlingoff of air under the coaches; that exhaust of air pressure may have indicated that the brakes were on with their fullest service pressure and the engineer was endeavoring to set them still tighter; for it may have been the exhaust from the High Speed reducing valve that you heard instead of the releasing air from the triple valve-sounds about the same, and such mistakes have already been made on other roads that use the High Speed brake.

Once in a while a triple valve is defective in that it sticks after an application, and you cannot release the brakes by bleeding the auxiliary reservoir completely; it is more likely to happen in very cold weather, on account of the triple valve freezing, but may occur at any time; you have always been instructed in such cases to remove the oil plug from the brake cylinder, bleeding the latter direct, and by which the brake is instantly released. Now, on cars haying the High Speed reducing valve there are no oil plugs; the plug was removed, and the pipe to the reducing valve is screwed into the oil hole in the brakecylinder head. How, then, can you directly bleed the cylinder in case the necessity arises? Well, both sides of the reducing valve are tapped for the brakecylinder pipe connection, the pipe is screwed into the opening most convenient to the cylinder and the opposite opening is closed by a 4-inch pipe plug; to bleed the brake cylinder, remove the plug in the reducing valve; or loosen the large union nut in the pipe connection to reducing valve; or, on some cars the pipe to reducing valve contains a tee with one of its openings plugged, the plug to be removed when it is desired to make an easy air connection to test the adjustment of the reducing valve, and sometimes it may

You may receive a passenger equipment car from another road, that has no High Speed reducing valve; of course that wouldn't make any difference just now; but after we have raised our brake-pipe pressure to 110 pounds and are actually using the High Speed brake, you must see to it that a foreign car coming into your train has a regular reducing valve, or a "safety valve"-a sort of pop valve -screwed into the oil hole in the brakecylinder head. Suppose it has neither? Well, you must carry one or more of those safety valves in your train box, unless it shall be decided to carry them on the engine, and hold the engineer responsible for having them on hand when needed; and in such cases you must attach the safety valves yourselves.

How do we know that the brake rigging and brake beams of the foreign car will stand the High Speed pressure?

one

reason for the safety valve. You see, the safety valve-unlike the regular H. S. reducing valve-is a plain style of pop valve set at about 50 pounds and with an exhausting capacity sufficient to blow off the excess of brake-cylinder pressure about as rapidly as it can enter the cylinder, even at emergency applications, and preventing the piston pressure from getting greater than is safe in the common quick-action brake system such as is used on the home road of the coach.

Before leaving a terminal station, when using the High Speed brake, the trainman should inspect each vehicle in his train and note that each one is equipped with the regular H. S. reducing valve, or else has the safety-valve attachment to the brake cylinder. And on arrival at your other terminal, be sure to remove and reapplied to any cars-foreign, or of your tain any safety valves that you may have (To be continued.)

own road.

But, a locomotive running reversed causes a suction through the exhaust passageways. If the supply comes from the smoke arch it results detrimentally to the cylinders and valves. Therefore the highly heated water from the boiler is used to supply the suction, and thus keep out the smoke, cinders, etc. It also acts as a lubricant. This boiler water does not enter the locomotive cylinders as such, but instead as wet steam. The effect of the compression is to farther heat it, so that the result is not very different on the cylinders and valves, so far as the water alone is concerned, than the use of low pressure steam.

When a blow-off cock is being used it will be observed that the boiler water turns at once to steam on reaching the atmosphere. This is because of its high temperature, the boiling point of the boiler water increasing with the steam pressure. This is the effect that follows when the boiler water enters the exhaust passageways in the saddle; it instantly turns into wet steam, and as such is drawn into the cylinders.

"Water" Brake Connections with Simple Locomotive.

Fig. 1 is a view from the back of the cab, looking forward, but with the firebox shown in bare outline only, and the machinery omitted up to the cylinders and saddle. The only provision out of the common arrangement is the half-inch globe valve tapped into the boiler head below the lower gauge cock, and generally about on a level with the crown sheet, its half-inch pipe connection running forward, dropping down immediately back of the cylinder saddle, where a T is connected. From the T two 3-inch pipes of equal length connect with the two exhaust passageways in the cylinder saddle.

Operation.-To operate the water brake, first open the cylinder cocks, and keep them open. With speed quite low place the lever in the reverse position, how far beyond the center being dependent on the holding power desired. At once open the water valve about half a turn and then note the discharge at the cylinder cocks. When the right amount of water is being admitted to the exhaust passageways the discharge from the cylinder cocks will be a dense white. If too

will be thin and light blue. Too much water will cause some to be thrown into the front end, and even out of the stack, particularly if the lever is near the center. Water in the smoke arch will be thrown out if steam is used heavily immediately after discontinuing the use of the water brake, thus dirtying the locomotive. The supply should be limited to the demand, as indicated by the cylinder cocks and stack, and the valve should be shut long enough before the lever is moved ahead to allow all water to be worked out of the pipes and exhaust cavities.

The lubricator should be kept feeding the same as when using steam, as the valves and cylinders are doing work and need lubrication. The vapor from the boiler water aids in lubricating, but is insufficient, particularly for the valves, in this being similar to when steam is used.

The small hole to be drilled in the pipe T is to prevent water accumulating and freezing in the pipe when the water brake is not in use. An automatic drip valve, opened by a light spring and closed by pressure in the water brake pipe, will accomplish the same result in a better

manner.

Baldwin Locomotive Works Back Pressure or "Water" Brake.

Figs. 2 and 3 illustrate an improvement on the water brake, same being patented by the Baldwin Locomotive Works. While illustrated in connection with their four-cylinder compound locomotive, yet there is no reason why its advantages may not be made use of with the simple locomotive.

The holding power is, as with the other arrangement described, due alone to the locomotive being run in the reverse motion. The highly heated boiler water is admitted into the exhaust cavities, as previously explained, the pipe being indicated in Figs. 2 and 3 by dotted line A, ending at a a, Fig. 3, where it has branched and entered the exhaust passageways.

But instead of the heated air, with its smoke and cinders, being drawn from the smoke arch into the steam chests and cylinders, the suction is supplied from the outside through air inlet valves C, Figs. 2 and 3. These open directly into the exhaust passageways, and the ex