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valve seat, put the valve on top of the board and block it in position and replace the steam-chest cover. If it is a balance valve, use a block of wood in place of the valve. If a piece of sheet iron is available use that to cover the ports under the valve. Generally one has to use what is at hand and that is a rule not of the best," replied Miller.

"That is true," said Tom Bailey. "A broken valve is not easily repaired. If you have a train of any importance, send for an engine, for between the tools you have to do the work with and the material you can obtain to use in fixing it up the engine will be there by the time you are ready, and at best you could only take a portion of the train alone," he added.

"Here comes the caller looking for trouble, so we will adjourn until some future day," said the Chairman.

W. L. FRENCH.

A Very High Grade Town.

Rossland, the metropolis of Middle British Columbia (in the famous Kootnai country), is noted chiefly for two things:

First, the number and richness of her mines; and, second, for her remarkably high railroad grades. It is of the latter that we would speak. Rossland is located about eight miles north of the international boundary line, and 17 miles nearly due north of the great smelter town of Northport. The latter point is situated on the south bank of the Columbia River.

Above sea level, Rossland stands 3,100 feet. Although less than 18 miles separate the town from Northport, yet the former is 2,000 feet higher than the latter. There is a branch railroad extending from Northport up to Rossland. Some idea may be formed of the grade between these two points.

After crossing the Columbia river, the railroad winds along through a dense forest for about two miles. This part of the grade is not heavy. Very soon Sheep Creek is reached. Here the heavy grade is encountered. For a mile or more the track runs parallel with the swiftly flowing stream. It is up, up, up, all the time. Large and powerful locomotives are used, but three passenger coaches are all that can be pulled up at one time.

For some distance the road extends along the west banks of Sheep Creek. This flows through a yawning canyon, and is several hundred feet below the

road. One may look from the car window away down on to the wildly rushing stream as it dashes over its rugged boulder bed. One's head grows dizzy as he peers down over the beetling cliff.

Further up the train passes in clear view of the beautiful Sheep Creek Falls. Here the stream makes a sheer leap of 100 feet. The waters are beaten into snow-white spume, and the thunder of the cascade may be heard for a long distance. Whenever the sun shines, a beautiful rainbow spans the stream at the foot of the falls. No more picturesque falls can be found in the Northwest.

Passing the falls, the road crosses the stream just above. The grade is less sharp until the boundary line is crossed a few miles above. Here the traveler passes from Uncle Sam's domain over on to British soil.

For some distance the road keeps in sight of the rolling, roaring stream, and finally bids it farewell and plunges off into the great cedar forest. Up, up, the great engine toils and coughs, fighting the sharp grade. Above the rattle of the train is heard the hard, dry puffing of the great "steel horse." Now the train crosses a deep, yawning chasm; then it threads its way up along the brink of a dizzy abyss; again it crawls along the sides of a lofty mountain hundreds of feet above your head and a thousand feet to the bottom of the canyon.

Above the road vast masses of rocks impend and over all tower giant forests looking down frowningly as the train toils below. Far beneath the shrinking eye glances over cliffs and yawning chasms. In and around these stupendous obstacles the shining road winds like a gigantic serpent. Here and there the track turns back upon itself. Distance is the only thing which can neutralize remorseless grades.

Before Rossland is reached two complete loops are made by the track. It is a long and fearful conflict between steel, steam and the power of gravitation. But the former triumphs, and, after more than two hours' incessant toil, the black, panting engine reaches the summit of the grade-2,000 feet above the Columbia River, and 3,100 feet above the glittering waters of the Pacific Ocean.

Vast quantities of ore are shipped from Rossland down to the Northport smelter. But it is a "downhill pull," and labor is comparatively light for the engines. However, the ponderous ore cars are difficult to pull up the long, heavy grade, and im

poses a tremendous strain and wear on the rolling stock of the company.

The construction of this road (a branch of the Great Northern Railroad, and known as "The Red Mountain Railway") involved the expenditure of a large amount of money. Originally it was built by D. C. Corbin, a millionaire, but was subsequently absorbed by James J. Hill. Its construction is one of the most remarkable pieces of railroad engineering on the Pacific Coast.

other way could the tremendous grades have been overcome.

Powerful consolidated engines are employed in hauling the passenger trains. Even with these engines only three coaches can be pulled up this long, heavy grade. One hour and 40 minutes are required to climb a distance of 12 miles.

As the Trail Smelter handles the total output of several large mines of Rossland, immense quantities of ore are shipped down to this great grade. All Rossland is the termini of two branch this work is performed by two very large

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roads. The other line belongs to the Canadian Pacific system. A "spur" runs from the little smelter town of Trail up to Rossland. Between Trail and Rossland the grade is much heavier than on the Red Mountain branch.

Trail is located on the Columbia River. As the "crow flies" the distance does not exceed seven miles; but, following the windings of the railroad, it is more than 12 miles. Again, some idea may be formed of the fearful grade, when the statement is made that Trail is 2,000 feet lower than Rossland.

This "spur" was built by F. Aug. Heintze, the great Copper King of Montana, but was subsequently sold to the Canadian Pacific and widened to a standard-gauge road. There are two switchbacks on this short piece of road. In no

"Shay" locomotives, which are driven by three vertical engines attached to a marine gearing. It is claimed that these engines are capable of performing as much work as two of the ordinary consolidated locomotives. These massively constructed Shay engines weigh about 100 tons, and have a maximum speed of about 10 miles per hour.

The altitude of Rossland is such as to win for that mountain city the sobriquet of the "High Grade Town." There are few towns on the Pacific Coast to reach which such heavy, short grades have to be overcome. Notwithstanding the heavy and dangerous grades and the fact that these branches have been in operation for several years, no serious accidents have yet occurred.

J. MAYNE BALTIMORE.

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Four-Point Lever.

In answering a question on the four point lever, asked by B. H. B. in the December number, the writer was reminded of another type of this lever, one that is much less objectionable than that asked about. It is shown in Fig. 1, together with the remainder of the general brake arrangement at one time extensively applied to tenders by a locomotive building concern.

Fig. 2 is a side view of the cylinder lever, and Fig. 3 is a view of the same from beneath. The lever consists of two bars carrying the three pulleys or sheaves. A is the cylinder connection and B is a bracket secured to the tender frame and is the pivot or fulcrum for the lever. A chain is passed around the pulleys and connects with the two rods. The purpose is to equally divide the force applied to the rods, the chain shifting around the pulleys whenever replacing worn brakeshoes, taking up slack or inequalities in the track tend to unequally distribute the force. Figs. 4 and 5 are to give a better understanding of the three cylinder lever arms that many find it difficult to see in the single lever shown by Figs. 1, 2 and 3. In all the figures from A to B is one lever arm, from B to C is another, and from D to B is the third. The arrangement illustrated by Figs. 4 and 5 would give the same result as the much cheaper design shown in the other figures.

The following rule, given for the fourpoint cylinder lever shown, does not necessarily apply with a differently arranged four-point lever.

RULE: Multiply the cylinder power by its distance from the fulcrum or pivot point, and divide the product by twice the distance from the fulcrum to one of the rod connections. The answer will be the force delivered to that rod.

Multiply the force delivered to this rod by its distance from the fulcrum, and divide the product by the distance from the other rod connection to the fulcrum. The answer will be the force delivered to that rod.

Applying this to the cylinder lever illustrated aud assuming a cylinder pressure of 2,500 pounds: 2,500 (force at A) multiplied by 20 (distance A to B) equals 50,000. The distance from one rod connection to the fulcrum (D to B), 10 inches, multiplied by 2 equals 20. 50,000 divided by 20 equals 2,500, or the force delivered to rod D.

2,500, the force delivered to rod D, multiplied by 10, its distance from the fulcrum (D to B), equals 25,000; and

this divided by 10, the distance from the other rod connection to the fulcrum (C to B), equals 2,500, or the force delivered to rod C.

While the equal lever arms show that this is so without the necessity of performing the calculation, yet this rule would apply to a theoretical proposition

where the two arms connected to the rods were not equal and where no equalizing chain was employed.

Neglecting the effect of friction where the chain and pulleys are employed, the force would be equally divided between the two rods even though the lever arms connecting to these rods developed different amounts. But, as a matter of fact, there is considerable friction in such a

cylinder lever arrangement, and as ir regularities of track cause the levers of the two trucks to move differently when the tender is in motion, the result is that this type of cylinder lever does not in practice equally divide the force between the two trucks even though it is properly proportioned.

As stated in the answer to the question by B. H. B., on page 890 of the December number, the four-point lever with the rigid rod connections is an impractiBut those interested in cable design. the theoretical side of the proposition may apply the rule given if it is assumed that both rods offer inflexible resistance at one and the same time, a condition impossible with a car or locomotive brake.

To test the correctness of any such lever calculation, multiply each force, whether that developed by the power first applied or the result of resistance to such, by the length of its lever arm. Add together in one column all such products tending to turn the lever in one direction and in another column add those resisting or tending to turn it in the opposite direction. If the calculation is correct the sums of the two columns will be equal to each other.

Illustrating this: 2,500, the force at A, multiplied by 20, equals 50,000. 2,500, the resistance at D, multiplied by 10, equals 25,000. 2,500, the resistance at C, multiplied by 10, equals 25,000. 50,000 is the product of the only force and its lever arm tending to cause rotation in one direction. This is opposed by the two lever arms B to D and B to C. Adding the products of their lever arms multiplied by the resistance offered at C and D equals 50,000. As this equals the other figure the forces are balanced, thus showing the calculation is correct.

F. B. FARMER.

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