classes of coal varies considerably in intensity. Often when an engine fired with poor coal is being worked hard, the coal can hardly be supplied in sufficient quantity to keep up the proper steam pressure. If your engine steams poorly don't jump at sudden conclusions, but stop and investigate, note how your fire burns, how the engine is being worked and its general condition. Make a close examination of all parts where defects are liable to exist, which course, with the application of a little thought and reasoning, is almost sure to result in remedying the trouble. When the difficulty is located report it in the work report book. There is always scme cause for an engine not steaming, and firemen having a proper conception of the importance and responsibilities of their occupation will, as a general rule, either make an engine steam satisfactorily or "know the reason why" it can not be made to do so. Next month's article will be entitled "The Engineer Helping to Keep the Engine Hot." Grease as a Lubricant for Locomotive Bearings. The committee appointed at the last convention of the Traveling Engineers' Association to report on the subject of "Grease as a Lubricant for Locomotive Bearings" specially desires the co-operation of all members of the association in securing information on results obtained in service with this method of lubrication. The committee has addressed a circular letter to each of the officers and members asking for replies to the following questions, together with any additional information on the subject: 1. Has the increased size of power, in addition to the pooling of locomotives so universally adopted, developed any necessity for a change in the method of lubrication? 2. Are you using grease or driving box compound as a lubricant? 3. State number of engines using grease or driving box compound on rods. 4. State number of engines using driving box compound on driving boxes. (Passenger).... (Freight).... 5. If grease is used on rods, describe form of rod cup, sending blue print if possible. 6. If you prefer a cup other than that used by your company, please furnish blue print or sketch giving special reasons for preference. 7. In compression rod cups give diameter of screw plug you prefer; 10. if a large diameter of approximately 2% inches, or one of a less size of 14 inches and number threads per inch. 8. Do you prefer a hexagonal or a square top of plug for wrench? Give size in either case. 9. State approximately number of miles run to one filling of cup with oil or grease. (Oil).... (Grease).... Give number of miles run per pint or pound when using oil in general as a lubricant; also when using grease as a lubricant on rods only, and also when using driving box compound as a lubricant on rods and driving boxes. The miles per pint desired is the total mileage made on valve oil and engine oil, and where grease is used the total mileage made on valve oil, and grease and oil combined. Miles per pint: When engine oil only is used: (Valve oil)... (Engine oil)... When grease is used on rods: (Valve oil).... (Grease and Engine oil).... When driving box compound is used in driving boxes and rods: (Valve oil). . . . (Engine oil and driving box compound) .... (Grease).... 14. If possible, give comparative data in the wear of brasses and pins, as between grease and oil as a lubricant. 15. Give figures as to number of hot bearings when using oil as a lubricant as compared with grease. (Oil).... (Grease).... 16. If the running temperature is higher when using grease as a lubricant than is the case with oil, has the increased temperature developed in any way detrimental? If tests have been made establishing any facts, please furnish data as to all points developed, favorable or otherwise. 17. What is your method of treating hot bearings where grease is used? Lubrication of Driving Boxes-18. If you have used any system of lubricating driving boxes other than the common practice followed throughout the country, please describe same, forwarding blue prints or cuts if possible; also give comparative figures of results between the old and the new method. 19. Have results secured with any new device for lubricating driving boxes developed any great economy in the maintenance of power in engine houses, and has there been any reduction in the time required for the preparation of engines for return trip or further service? In order that the committee may have sufficient time for the final preparation of the report it is especially desired that all replies to the circular of inquiry be forwarded on or before June 1st, to the chairman of the committee, E. W. Brown, Chairman, Traveling Engineer, D., L. & W. R. R., Scranton, Pa. Don't think for a minute that an engine will steam better hooked up so close to the center that the exhaust does not work the fire. Another think on this subject is to keep a heavy, thick fire alive. Many an engine must be worked pretty well down towards the corner, when, if the fire was of the right thickness and even, she would make more steam and use less in one of the higher notches. Don't think for the last three hours of the trip that the only reason for cleaning the ashpan is to keep from burning the grates. You must give room for the air to get through the pan to the fire, or every time you open the door to put in a fresh fire too much air goes in at the door, and then the steam drops back five pounds. Air should come through the fire. Don't ever think that you can preach one method of handling machinery and practice another. Mankind is credulous and will believe some things that are not so, if skilfully presented by an expert. But the locomotive and air brake don't care for arguments and don't believe at all; they just act. The uncomfortable point about a machine is that when it makes a mistake or is defective it spoils the whole job. Don't think for a minute that you can lay down your idea in the air brake car as to how a smooth stop should be made and get a high percentage on your examination, and then on the engine use the emergency application and the reverse lever to make a water tank stop and not get caught at it. The man in the way car who gets banged around will tell all the other men on the road-maybe he will tell you. Don't think for a minute that because compressed air will work the blower when firing up, or move a locomotive around the engine house, that it will work an injector and force water into a boiler against the air pressure that you expect to use to work the injector. Try it, and you will find that you have another think coming, and the next think will be "what makes an injector work?" Don't think for a minute that a big firebox and a generous grate surface is any help to an engine if you let a big clinker form that covers a large share of the grates and reduces the area for burning coal. The Hudson River Tunnel. March 11, 1904, marks the successful culmination of the work begun thirty years ago on the Hudson River tunnel. On that day the junction was made between the New Jersey heading and the old New York section of the north tube and Mr. William G. McAdoo, President of the New York and New Jersey Company, was accorded the honor of being the first man to pass from Jersey City to New York under the Hudson River. The progress of this tunnel from its inception up to the present time has been Proposed Extension of the Hudson River Tunnel (From Scientific American) 1874. A shaft was sunk at Fifteenth street, Jersey City, and at the foot of Morton street, New York, and from the bottoms of these shafts twin tunnels were run out under the river. In carrying out this work no excavating shield was used, as it was thought that the silt was sufficiently compact to hold its position until the two-foot brick lining was set in place. This surmise proved incorrect, and it was found necessary to use a fivefoot pilot tube, which was pushed ahead of the main tunnel and used as a center for radial braces, which supported the tunnel wall under construction. The work was carried on without serious accident until in July, 1880, the shallow layer of silt betwen the tunnel roof and the river gave way under the pneumatic pressure in the tunnel, and the inrushing water drowned twenty of the workmen. The work was then continued halfheartedly for two years, when, with 2,000 feet of the north tunnel completed, it was abandoned. In 1890 an English company took up the work, using an excavating shield, and working from the Jersey end carried the tunnel forward to within 1,500 feet of the old New York heading. Again the work was abandoned until 1896, when the New York and New Jersey Company took charge of the work, and in 1902 began the work which has since been carried out to its present successful issue. This magnificent engineering achievement of Jacobs and Davies, engineers of the New York and New Jersey Company, in accomplishing that which had twice before been attempted and abandoned, is deserving of highest praise, particularly in view of the fact that difficulties were met and successfully overcome, which the other companies did not encounter and which, in fact, the engineering world has never before been called upon to master. The work had progressed only a few hundred feet when rock was encountered in the lower part of the tunnel. The excavating shield in use, the one that the English company had installed, was designed to be forced through silt, and it would merely have crumpled into a shapeless mass if it had been forced against this rock barrier. It was necessary, therefore, for the workmen to advance beyond the cutting edge of the shield, and blast out this rock before moving the shield forward. If the rock had covered the entire face of the shield, this would have been a comparatively easy matter: but the engineers were confronted by the unique problem of driving the floor of the tunnel through rock and the roof through silt. To meet these conditions, it was found necessary to build an apron out in front of the shield, which would protect the workmen from the silt above. This apron, as shown in one of our illustrations, extended from side to side of the tunnel shield near its center line, and projected forward about 6 feet. It was built of 3-4-inch steel plates laid on brackets formed of 12-inch I-beams. This apron enabled the workmen to attack the rock without fear of being smothered by an avalanche of the soft silt above. Even with this protection the work was not without danger, as the rock varied in height from 1 to 16 feet. Fortunately, no casualties resulted, and the passage |