great engineering works of the year. The special construction of the hydraulic shields need not here be described in detail, as the prin

ARIO

MAP SHOWING LOCATION OF TUNNEL.

ciple has long been known to the engineering profession. Substantially it is a section of large pipe surrounded by another movable section of pipe, the latter having a cutting edge and being capable of movement through the action of powerful hydraulic rams. The cutting edge is thus pressed through the soil, and a compartment between the movable section and the fixed section gives working room for several men who throw the material excavated back into the fixed tunnel whence it is transported to the heading on small cars. Two shields of this description were used, one at each end of the tunnel, and the two met, their circular edges coinciding almost exactly, under the middle of the river. The very difficult soil mentioned in connection with the experimental shafts extended all the way under the bed of the river, and was at times so nearly fluid as greatly to delay the progress of the work. Experience taught the engineers how to deal with it, and no serious accident occurred during the period of construction. The chief obstacles encountered were due to the occurrences of large bowlders imbedded in the clay, against which the advancing shields occasionally struck. Blasting was impossible under the existing conditions, and accordingly they had to be split by hand drilling and wedge work or other primitive devices. Masonry is not employed in the tunnel proper, the entire excavation being lined by flanged, segmental cast-iron plates (see figure). The flanges rest against one another, and bolts are passed through the holes of each two contiguous segments. Thirteen of these cast-iron segments complete the circle of the tunnel, with a small key SEGMENT OF CAST IRON OF Segment at the crown of the arch. Each seg

WHICH TUNNEL IS COMPOSED.

ment is 4 feet 10 inches long, 18 inches wide, and 2 inches thick; the flanges are 6 inches deep inside, and 14 inch thick; the segments are cast with 32 bolt holes in each, the bolts being inch in diameter. This makes an exceedingly strong structure, and with proper precautions against oxidation should be practically indestructible. The total length of the tunnel is 2,267 yards, of which 777 yards is under the American side of the river, and 770 yards under the Canadian side. The central section of the

maximum below the surface of the water 664 feet. The cross section of the tunnel is circular, with an interior diameter of 20 feet, admitting but a single line of rails. The total cost at the beginning was estimated at about $2,500,000, of which the Dominion Government granted the company a subsidy of £77,625. The latest attainable figures show that about 200,000 cars were transferred by ferriage across St. Clair river in the year, an average of over 500 a day. It is evident that the tunnel will largely facilitate the regularity desirable for this enormous traffic. It is extremely probable that increasing business will necessitate the duplication of this tunnel before many years. The work of construction has been under the charge of Joseph Hobson as chief engineer.

In this connection it may not be amiss to call attention to the different interstate relations of the United States and Canada, and of Great Britain and France. In one case a tunnel is built with hardly a word of protest; in the other Parliament can not be induced to grant a permit for construction.

Tunnel and Electric Railway.-One of the great tunnels of the year passes under some of the most densely populated portions of London, from King William Street, in the "City," under the Thames, to Stockwell, about three miles, with intermediate stations. The company has the chartered right of way to Clapham Common, one mile farther. The line is tunnel work throughout. It was opened to the public on Oct. 28. The work of excavation was done by a movable shield of the Beach pattern, similar to that used in the St. Clair River Tunnel, an American invention long familiar to our engineers. Most of the line passed through stiff clay, such as underlies a large portion of the city. Owing to the importance of preventing any subsidence at the surface of the earth, it was necessary to force grouting cement into the space surrounding the cylinder. This was accomplished by an opening in the segmental iron plates lining the tunnel, through which the cement was forced at a high pressure. The end of the line near King William Street station is peculiarly arranged, owing to the value of horizontal space. Two tunnels are made, one for public traffic and the other for railway traffic. At the start these are placed one over the other, but the relative position changes while passing under the river, and they are side by side before reaching East London. The tunnels are 10 feet and 6 inches in diameter. Electricity is used throughout as a motive power. There are three large generating dynamos of the Edison-Hopkinson type, each worked independently by an engine of 375 horse-power. The efficiency of the dynamos is 95 per cent., and the measured applied efficiency of engine and dynamo is 75 per cent. There are fourteen electrical locomotives for the traction work, each intended to develop 100 horse-power and a speed of 25 miles an hour. The armatures of the loco

motives are constructed so that the shaft serves as the axle of the locomotive, a device suggested by the late Sir William Siemens, but not before used in the British Islands. The locomotives have a motor on each axle, and collect the current through an ampère metre, returning it to the rails through regulating and reversing switches, magnets, etc., thus completing the circuit. Each train will weigh about 30 tons loaded, and 10 trains can be worked at once. The construction of the work has been under the charge of J. H. Greathead, civil engineer

Tunnel of the Great Northern Railroad Company.-Increasing traffic made it necessary to construct a short tunnel, passing under some of the heaviest business buildings and the busiest streets of the city of London. Some special system of construction was necessary, in order that traffic might not be interrupted. The plan adopted was the invention of Messrs. Jennings and Stannard. Instead of the ordinary timber work used in tunneling, steel bars, technically called "needles," were used; cross sections of these are shown in the following illustration.

Each needle is 10 feet long, 6 inches wide, and 2 inches thick, so arranged that when laid side by side overlapping they admit free longitudinal motion and can be adjusted to fit an arch of any radius. When the initial excavation is made the needles are inserted like ordinary tunnel bars covering the crown of the arch. Brick work is built up immediately under the needles, and each needle can be forced forward by means of screwjacks. Longitudinal cavities extend through the needles, so that grouting can be forced into the spaces that are left as they advance. The excavation is made exactly the size of the tunnel, plus the thickness of the needles. At King's Cross Station the line ran under the freight yard, only three feet of earth remaining between the crown of the arch and the surface, on which very heavy traffic was continually passing. Tunnels or drive-ways made after this manner are less expensive, and, in many ways, more convenient. For instance, in the case of sewers, the exact shape can be made at once, instead of driving a square heading at first.

Lumber Flumes and Chutes in California. -The enormous extent of logging operations in the red-wood country of California has necessitated a special system of engineering as these magnificent trees disappeared from the immediate neighborhood of the coast and the natural water ways. No one can witness the reckless destruction of these superb forests without regretting that improved systems of cutting, shipping, and handling can be brought to bear upon them.

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The forests are disappearing so rapidly that two or three generations may witness their extinction, unless wise legislation can be introduced in time to save the red woods. Some of the engineering operations are ingenious and interesting. The country being very hilly, great care is taken in felling the timber, and the enormous size of the logs renders it extremely difficult to transport them to a market. On entirely level ground it does not pay to haul logs more than a quarter of a mile, since it takes 12 or 14 cattle to a log; moreover, a road must be prepared, and it is usually cheaper to run a short railroad directly into the timber. This has been found to be very expensive work in a hilly country, and within a few years the construction of lumber flumes has been largely introduced. These are most extensively used in the northeastern part of the red-wood district. The flumes are all constructed on what is known as "the V section." They are made of boards, 20 inches wide, battened on the outside wherever necessary. The V is 5 feet across the top and supported by ordinary staging work, usually somewhat rough. The flumes sometimes run for long distances at an angle of as much as 45°, but, in order to check the rush of the lumber, it is necessary that a long stretch of level flume should always follow these steep descents; in these the water reduces its velocity to a manageable rate. A flume can be built and put in operation at an expense of about $5,000 a mile, though the cost is sometimes $15,000 a mile, according to the amount of timber work and excavation. These flumes will carry about 100,000 feet of lumber and 50 cords of wood a day. For operating, one man is required for each 5 miles of flume, and a foot way is constructed along the entire length. The average speed of water approximates 5 miles an hour.

One of the largest flumes now in operation is known as the 60-mile flume, near Chico, Cal. It is constructed substantially on the plan indicated above. As an accessory to the flumes, chutes are common, especially on those sections of the coast where it is impossible to load vessels from the wharf. In many instances, indeed, there are no harbor facilities whatever along this coast, nor is it possible to construct them without great expense. The presence of dangerous rocks compels vessels to anchor several hundred feet off shore, and the ceaseless swells that roll in from the Pacific further complicate the problem of safely delivering large logs from the high bluffs of the shore. The stationary work of the chute generally extends two or three hundred feet from the land, with an attachment called an apron extending from 40 to 90 feet farther. The chute proper is constructed on lofty timber underpinning, with guys reaching in either direction, and anchored to the shore in order to prevent dangerous swaying from side to side under the influence of the breaking sea. The apron, so-called, is made fast to the end of the chute by very heavy hinges and by guys extending to supports built upward from the main scaffolding. The guys are arranged as running rigging passing over blocks and raising or lowering the apron, according to the condition of the sea or the height of the tide. The apron is usually held at the height of 5 or 10 feet above the rail of the ves

sel, thus allowing the vessel to rise and fall that distance without interference. A contrivance called a brake is attached to the lower end of the apron and operated by a set of levers connected with the chute. From 7 to 10 men are required to handle lumber from the tracks or cars to the deck of the vessel, and for a gang of this size 50,000 feet is considered a good day's work. The cost of a chute is from $2,000 to $6,000, according to the difficulties.

Wire chutes have lately been introduced, since they are found to be much more convenient in case of heavy on-shore winds. A vessel pitching violently at her anchor can be loaded almost as easily as if she were lying in smooth water. Three-inch flexible steel-wire ropes are used. These are passed around a drum, which is driven by a donkey engine, thence out between the vessel's masts, resting on supports connected with the masts, and so arranged as to be raised or lowered. The main wire rope then extends some. distance beyond the vessel, and is securely anchored to the bottom of the sea. On this rope a traveler works back and forth carrying the load down the wire by means of a series of wheels. The traveler, of course, is fitted with a set of chains and hooks and hoisting tackle, by means of which the lumber in any form can be picked up and delivered easily on deck. Of course all possible precautions are taken for the security of the cable anchors, and of preventing the vessel from dragging her own anchors and fouling the wire chute. One advantage of the wire chute is that its peculiar elastic construction allows it to move with the vessel in stormy weather, which, cf course, is out of the question with a stationary chute. Moreover, it works far more rapidly than the other kinds of chutes, and is capable of carrying from 1,500 to 2,000 feet of lumber at a load, delivering as many as 1,000 railroad ties in an hour. Seven or 8 men are required to operate the wire chute, and the expense of its construction does not vary greatly from that of a less scientific variety.

Submerged Railway on the Coast of Spain. -Somewhat similar in its general purpose to the lumber chutes on the coast of California is the submerged railway connected with the mines of Onton, near Bilbao, on the northern coast of Spain. These are rich iron mines, long worked, but, as the coast is extremely precipitous and difficult, great trouble has heretofore been encountered in shipping the ore. At the foot of the steep rocks is a sloping bottom, which extends some distance at an even grade. On this incline a railroad bed was made, about 650 feet long and 20 feet wide, and on this two sets of parallel tracks were placed, making a four-rail road. The grade is 5 feet in 100. The car that traverses this railway is a high metallic pyramidal tower, mounted on four sets of wheels running on the fourfold track described. The platform on which the load of mineral ore is placed is about 70 feet above the track, high enough, that is, to rise well above the decks of ordinary vessels. This tower, while movable on its wheels, is of course practically stationary as regards the action of the sea. The ore, therefore, can be delivered by simple inclined chutes from the mouths of the mines and loaded upon the upper platform of the tower. The motive

power is furnished by gravity, the loaded tower running seaward by its own weight, controlled, of course, by brakes and cables connected with the shore. To draw it back when empty, the power of a gravity road on shore is employed. Several weighted cars are placed on an inclined plane for this purpose, the connection with the tower being made by strong cables running over sheaves. The tower thus works, loads and unloads itself almost automatically, and the railway operates without difficulty. When the sea is extremely rough, mooring buoys are provided at the outer end of the railroad, to which vessels can be made fast. The credit of this undertaking is due to D. M. Alberto de Palazio. The platform carries for its load about 100 tons of ore, and 5,000 tons a day can be delivered on shipboard: The total cost of the apparatus was about $18,000.

Chimney of the Clark Thread Works.-At Harrison, N. J., is the highest chimney in the United States, the property of the Clark Thread Works. Its total height is 335 feet. It is a conspicuous feature of the landscape between Newark and New York, familiar to tens of thousands of passengers who pass daily within sight of it on the adjacent railroads. On March 28, during an unseasonable thunder storm, this lofty

ing down one side, throwing into the air a cloud of bricks and débris. By a curious coincidence, scarcely a quarter of a minute later a second stroke fell upon the same spot, thus effectively exploding the time-honored saying that lightning never strikes twice in the same place. By a singular omission, no provision had been made for ascending the chimney, but after this accident it became necessary to inspect its condition. It was deemed unsafe to continue working the factory, and the mill was accordingly shut down until the tower could be examined. A roofer, John Phillips, commonly known in Newark as "Steeple Jack," was finally consulted, and he undertook, for a stipulated sum, to climb the chimney within a specified time. The undertaking involved a bit of personal engineering

TOP OF CHIMNEY OF THE CLARK THREAD WORKS.

that deserves perpetuation, especially as he accomplished his task in three working days. The side of the chimney opposite to that struck by lightning was selected. A ladder was first placed against the chimney, and a block of wood inserted between its upper end and the brick work. The block was a little longer than the width of the ladder. Phillips ascended this first ladder and drove two straight-shanked hooks of steel into the joints between the bricks, just outside the sides of the ladder, their bending ends projecting inwardly and firmly gripping the ladder itself. A second ladder was now drawn up with block and tackle and lashed securely to the upper section of the first ladder. A steel hook was then driven into the chimney far enough up to hold the second ladder securely until the climber could ascend and fasten the second ladder with hooks and a block driven in as before, at the head of the ladder. This process was followed, as shown in the illustration, as far up as

the taper of the chimney continued uniform. Twenty-four ladders brought him to the outward flare of the brick work. Near the top of the uppermost ladder precautions were taken for security by driving additional hooks into the chimney; then a ladder long enough to reach to the outer rim of the chimney cap was hoisted and cautiously shoved out by means of tackle and blocks until its upper end projected above the outermost rim of the chimney cap. This ladder, inclining outward, was securely lashed, and the daring climber ascended it to the extreme top of the chimney. This done, of course the hoisting of timbers and the construction of a working platform for repairs to brick work was a simple matter. The operation of climbing attracted a great deal of attention from the thickly populated adjacent regions. With a good telescope in clear weather the man could be seen from New York, and the passengers on passing trains crowded platforms and windows on their way to and from the city. Phillips is a member of a slate and felt roofing firm of Newark, N J.; he is a slightly built man, Scotch by birth, and undertook this climbing feat merely as an incident of his every-day life.

Electric Engineering.-The activity alike in the invention and development of all kinds of electrical appliances has been very rapid, the United States leading in many directions. In the employment of electricity for traction America is far in advance of the rest of the world; but tramways are now being introduced in Europe. One that has been brought into successful operation near Berlin is about one mile long and is operated on the Thomas Houston plan. In electric lighting the main progress has been in the direction of making glass bulbs at less expense, and securing more perfect vacuums for the incandescent lights. In the direction of introducing electric lights on steam and tram cars, some progress has been made, but their introduction is by no means general. Among the new applications of electricity are the rendering of car brakes more efficient in their action, and by a simple appliance causing the wheels to take better hold upon the tracks. Electric search lights, heretofore mainly confined to war vessels, are now introduced on passenger steamers and are a great source of safety in thick weather and in the detection of possible obstructions. Electric welding and the discharge of guns by electricity have attracted attention from engineers.

Among the important engineering works in progress are the great breakwaters at Yokohama, in Japan. These are said to be wholly under the direction of native engineers.

The triple tunnel across the Clyde is well under way, and may be finished next year. In connection with the Manchester Canal, mentioned above, large improvements in the navigation of the Mersey river are in progress at and below Liverpool. On Sept. 15 work was inaugurated for the opening of the famous iron gates of the Danube, near Greben. This work is partly in Hungary and partly in Servia, and is designed to circumvent the rapids of the Danube. It will probably not be finished until 1895.

The Chignecto Shipping Railway, connecting the Bay of Fundy with the Gulf of St. Lawrence, is the pioneer of first-class railways of this de

scription. A large part of the permanent way has been completed, 17 miles are graded and ready for the rails, and the masonry for the great hydraulic lifts at either end of the railway is well advanced. The lifts are calculated to raise 2,000 pounds to a height of about 40 feet.

The tunnel under the Hudson river between New York and Jersey City is making fair progress at the rate of about 8 feet a day, and may be finished during the coming year.

Work has been begun on the fine bridge across the Danube, connecting Roumania and Dobrutcha. It is to cross between Czernavoda and Tetesti. The bridge proper will be 2.460 feet long, in five spans, and when completed will be one of the finest in Europe.

EVANGELICAL ASSOCIATION. The following is a summary of the statistics of this denomination for 1890: Number of conferences, 26; of itinerant preachers, 1,227; of local preachers, 637; of members, 148.508; of churches, 2,0434, having a probable value of $5,047.853; of parsonages, 681, valued at $831.717; of Sundayschools, 2,509, with 28.420 officers and teachers and 176,557 pupils; of baptisms during the year, 2,668 of adults and 9.436 of children. Amount of collections: For conference claimants, $7,529; for the Missionary Society, $107,873; for the Sunday-school and Tract Union, $2,494; and for the Orphans' Home, $5,570.

The receipts of the Missionary Society, as returned by the treasurer for the year ending Aug. 31, were: For home missions (general treasury), $31,019; for the European treasury, $3,720; for the heathen treasury, $7,496; for conference treasuries, $91,811; total, $134,047. The expenditures were $158,629, showing a deficiency of $24,482. The society has a permanent fund of $74,320, a current fund of $4,950, and annuity fund of $50,612.

Controversy over the Bishops. This Church has been disturbed by a controversy which has penetrated to every part of it, has divided conferences and local church organizations, and threatens to be the source of most serious embarrassment, if not of complete and permanent division, at the General Conference of 1891. It turns immediately upon the position and official standing of the three bishops, Rev. Rudolph Dubs, Rev. J. J. Escher, and Rev. Thomas Bowman, but arose in 1885 over questions concerning the administration of the mission in Japan, and has been traced back to the election of bishops at the General Conference of 1875. Affairs in the mission in Japan requiring episcopal attention in 1885, an official visit was made there by Bishop Escher, and resulted in his preparing a report unfavorable to the superintendent. The bishop's course was attacked by the "Evangelical Messenger," the Church periodical, the editor of which was a brother of the superintendent, and he was removed from office on trial by the General Conference of 1887. A paper in opposition to the official journal was begun, of which the suspended editor was made conductor. Bishop Dubs, whose sympathies were with the superintendent of the Japan mission, was accused of slander for some charge he had made against one of the persons active in the controversy; was tried in accordance with the forms of the Church, and suspended from his office until ac

tion could be taken by the General Conference of 1891. He has paid a formal obedience to the sentence of suspension. Charges having been brought against Bishops Bowman and Escher, they procured a preliminary investigation, as is required by the discipline of the Church, before a court of three elders, who declared that no cause of action was shown against them. They claimed that these proceedings were a final disposition of the case and of their liability on those charges. The adherents of the other party disputed this position, and attempted to subject them to full trials. A court sitting in the case of Bishop Bowman at Chicago declared, March 7, that be be suspended from the exercise of his episcopal functions. A similar court sitting at Reading, Pa., pronounced a like sentence against Bishop Escher, March 21. Both bishops, taking the ground that these later proceedings were forestalled by the decision of the preliminary court of three elders, have disregarded them as void, and have continued to hold conferences and exercise episcopal authority. In this they have been sustained by the majority of the conferences and members of the Church. The Church has, therefore, no bishops whose authority is recognized throughout its borders; and frequent conflicts arise over questions of authority or the possession of property, which have to be taken to the civil courts. As yet no final decision has been made over any of these cases, either in the courts of the Church or of the land. While the controversy appears in its outward manifestations to be mainly a personal one, the leaders of the minority party, or those who support Bishop Dubs, assert that a fundamental question of church polity lies at the bottom of it. This question is said to concern the nature of the office and the extent of the authority of the bishops in the Evangelical Association. The minority accuse Bishops Bowman and Escher of unduly exalting their office, of usurping functions not conferred upon it by the constitution of the Church, and of arbitrary and unjust exercise of the powers which they are thus accused of having taken to themselves.

EVENTS OF 1890. The year has been without events of very great international importance, but the general drift of affairs has been significant. The frequent occurrence and serious character of strikes all over the civilized world has been especially noteworthy. So too has been the stand taken by the German Emperor in behalf of labor interests, and the conspicuous failure of certain strikes that were obviously instigated by demagogues. The rival European powers appear to have agreed that a peaceful adjustment of boundaries in Africa is better than settling disputes by war. The great Republic of Brazil has seemingly passed beyond the experimental stage. The Behring Sea question between the United States and Great Britain bids fair to be peacefully settled by arbitration, and the Pan-American Congress points to international harmony on the Western Continent. In politics the most sensational event was the rupture between English Liberals and Irish Nationalists. The list given herewith includes most of the occurrences that, from day to day, have commanded a considerable share of public atten

tion.