secondary consideration. The idea took no practical form during two centuries, though mooted from time to time. At last, in 1823, D. Mentz revived Dou's plans of 1634 with such deviations only as were unavoidable through the reclaiming of the Haarlem Lake. The principal feature of this proposal was the construction of a dam at the entrance to the Y from the Zuiderzee to obtain a closed fresh-water basin so as to replace the storage capacity diminished by the drained surface of the Haarlem Lake. The opening of the large navigation canal through North Holland in 1825 caused the shipping interest to lose all concern in these plans, and they were thus wholly relegated to water-supply and drainage. In a project by Kloppenburg and Faddegon, published in 1848, and in that by Van Diggelen, of 1849, trade interests were again more considered. Both followed principally the lines laid down originally by Dou, with schemes in connection for the drainage of a large part of the Zuiderzee.

In 1852 the City Engineer of Amsterdam, W. A. Froger, took the subject in hand, and it was principally due to the indefatigable exertions of this able engineer that the old idea of giving Amsterdam a direct communication with the North Sea obtained a more concrete form. His plans, however, were not accepted, but a number of different solutions were proposed, amongst others, those by a Government Commission appointed to investigate the subject. In the report of this Commission an inclination is shown to follow the principles of the Suez Canal, and the new waterway to Rotterdam, both open channels without locks or impediments to the free entrance of ships. It is remarkable that these considerations were again lost sight of in later schemes, and at the present moment regret may be felt at this change of feeling, as in some quarters doubt is expressed whether the dimensions of the new locks about to be built are not already insufficient for admitting the largest ships that may be expected to visit the port. The plans submitted by A. Caland and Lankelma proposing lockless fairways appear, in the light of subsequent experience, preferable to the works actually constructed.

The writer considers the time opportune to reopen the question now that enlargements are contemplated, which will demand heavy outlay, and wishes to remark that the plural of ship is not ships, but fleet, and that a fleet requires open channels for its untrammelled movements. The increasing trade of Amsterdam reasonably demands a communication with the ocean equal in capacity to those of Rotterdam or Antwerp.

A great number of drawings accompany the Paper.

H. S.

Progress of the Works of the Baltic Ship-Canal.

By F. WOAS.

(Deutsche Bauzeitung, 1889, p. 440.)

These notes are unofficial and the result of personal observation of the works, and particulars ascertained on the ground during a visit paid by the Author.

The canal was commenced two years ago, and is the largest work of the kind hitherto undertaken in Germany; when completed it will be 61 miles long. Its course throughout is now definitely fixed, and is laid out so as to avoid the town of Rendsburg, instead of utilizing, at that point, the existing Eider Canal (running through the town) as originally contemplated. The working-drawings for the locks being still in progress, their construction will not be commenced this year; but a large quantity of building-material is already delivered at the sites. Of the many crossings of the canal, only one will be a fixed structure, viz., that at Grünenthal, about 183 miles from the Elbe, which will be an overbridge carrying the railway and high road from Neumünster to Heide. The German Admiralty required an opening of not less than 121 feet 6 inches span and 138 feet headway, so as to allow of the passage of ships of war without striking their top-masts. The bridge to be constructed will have a span of 820 feet 3 inches, and to obtain the requisite headway, it will be necessary to construct an embankment of considerable height, although the canal at that point is in a cutting of 108 feet 3 inches deep (to canal bed). The various buildings intended for the offices, dwellings of the harbourmasters, lock-keepers, and others of the working staff, are well advanced; and barracks for workmen engaged in the construction have been erected at various points along the canal course. Twelve of these latter were noticed, of sizes sufficient to accommodate from one hundred to five hundred men. It was supposed originally that very considerable barrack-room would have to be provided; but it is now found that the buildings already erected are more than sufficient for the purpose, as the number of labourers requiring quarters is much less than was at first expected. This is due to the vicinity, in the eastern portion of the canal, of the towns of Kiel and Rendsburg, and on the westward section, of the villages of Hanerau, Albersdorf, Burg, and Brunsbüttel, from which supplies of labourers may be drawn; the conveyance of men and delivery of material being rendered easy from the fact that the line of canal is intersected by four lines of railway and ten highways.

The foregoing circumstances naturally tend much to facilitate, and to lessen the cost of, construction, to which may be added the conveniences afforded by the waterways of the existing Eider Canal in the eastern district, possessing locks of 26 feet 3 inches in breadth, and a depth of water of 10 feet 6 inches; and in the western portion the Burg-Kurdensee Canal, the Burger Au, and

the Holstenan. The rate of wages, however, is abnormally highan ordinary day-labourer being unobtainable at less than 28. 7d., or as a rule 38.; and foremen, gangers, machine-attendants, &c., command 108. per day, which includes quarters.

As regards the present position of the works in general; at the Elbe end, about one-fourth of the excavation for the lock is completed, and a landing-stage and cranes are being erected by the works-executive for the delivery of stone brought from Meissen, conveyed in the Elbe barges to Hamburg, and thence by sea-going vessels.

An enumeration is given of the various places where excavation is being executed. Throughout the Elbe-level the works are light, but at 10 miles, where the canal leaves the latter, the first heavy cutting (49 feet 3 inches to canal bed) occurs. There are here at work one mud-dredger (Nassbagger), and several steam-navvies (Trockenbagger). The contract price is 9d. per cubic yard. The works are untouched between 13 and 17.4 miles. At 18.6 miles the Grünenthal cutting has been begun, and the works are being prosecuted vigorously, there being seven steam-navvies at work day and night, and fourteen locomotives are employed in running out the "muck" to form the above-mentioned embankment. From this point there is a length of 24.8 miles untouched; but the works on this section will be of a very light character (say 11,000,000 cubic yards in all). At 6.2 miles beyond Rendsburg the works in progress recommence. Here the course is identical with that of the old Eider Canal, excepting where the sharp curves of the latter have been improved, and then part of the waterway passes through the Eider See, after which the Eider Canal is departed from, and for a length of 6.2 miles the course is in cutting, ranging from 33 feet to 49 feet in depth. The excavation is used for the embankment across a short stretch of moorland. Here there are two steam-navvies at work, which, owing to the nature of the soil (light dry sand), deal with 2,700 to 3,300 cubic yards per day, the contract price being 6 6d. per cubic yard.

The Flemhuder See is traversed for about mile, the course being the same as that of the old Eider Canal, it being, however, necessary to dredge sufficient to attain a depth of 23 feet of water, which is now being effected; the normal level of the lake is preserved by a dam on each side of the canal. From this point to the termination of the canal, at its outlet into the harbour of Kiel, the works have been commenced at several isolated places where the new canal deviates from the old, five steam-navvies being in operation, and at the site of the Holtenau Lock one of these machines is at work. Lastly, a dredger is employed in deepening the channel in the harbour.

It is expected to divert the navigation from the old to the new canal in 1893.

D. G.

Rope-Haulage Trials, Oriolle System. By P. DE MONICOURT.

(Le Génie Civil, vol. xvi., Nov. 2, 1889, p. 3, 5 woodcuts.)

The improvement of the inland navigation system of France has produced a rapid increase in the number of the vessels traversing the waterways, so that the tonnage has augmented 30 per cent. This increase, however, by encumbering at times the principal waterways, has raised the cost of transport, so that haulage by telodynamic cables is being tried. The earlier experiments of Mr. Oriolle, on a section of the St. Quentin Canal, which failed to keep the cable in place, indicated that the three following conditions should be realised:-(1) To place the cable on its supports, so that it is unable to leave them, whilst reducing the friction to a minimum; (2) to enable the boatman to attach his barge to, or to detach it from, the travelling cable at pleasure; (3) to furnish the barge with an apparatus for gradually increasing the traction at starting, and preventing it exceeding a given maximum in the event of the barge grounding or other accident. The grooved pulleys supporting the cable are hung from their supports, and provided with a counterpoise weight at the opposite end, so that they readily adjust themselves to any suitable plane according to the varying tension of the cable, which is thus kept in place. The tow-rope is attached to the cable by a metal fastening called a menotte, which consists of a metal socket enveloping the upper part of the cable. The socket contains three steel rings, formed in two pieces, so as readily to encircle the cable; and a two-armed lever either pushes up the central ring when pulled by the towrope, and thus wedges the cable between the rings and imparts its motion to the tow-rope, or releases the menotte by a pull on the other arm with the cord controlled by the boatman, which then slides on the cable. The turning of the cable, moreover, in its onward motion, does not affect the tow-rope, as the steel rings can turn in the socket. The tow-rope is wound round two bitts, with castiron jaws, placed on the barge. In starting, the rope, in winding, turns the bitts, and gradually presses them more and more against their conical pivots, and a ratchet arrangement prevents the maximum tension of 100 lbs. being exceeded, though this tension can be modified if desired by a modification of the tension of the spring in the apparatus. The tow-rope is attached to an unlocking lever, so that when the tension on the rope is suddenly increased by the barge running into the bank, grounding, or any other cause, the pull on the lever makes it release the bitts as soon as the tension exceeds the arranged maximum, so that the rope is slackened, whilst the cord for unloosing the menotte, remaining unaltered in length, soon exerts the necessary pull, and releases the tow-rope from its grip of the cable. The portion of the St. Quentin Canal on which these trials were made is nearly 1 mile 7 furlongs in length, and traverses three locks, two bridges, and two curves, one of them with a radius of only

5 chains. The cable is composed of six strands of seven wires each, with a sectional area of 0.285 square inch. At each end of the course, the cable crosses the canal on horizontal pulleys. The cable borders the canal on each bank outside the towing-path, and is carried on pulleys suspended from light braced standards placed about 200 feet apart, the sag of the cables midway between the supports being about 2 feet. Where the canal is widened out at approaches to locks, causing a deflection of the towing-path, a long horizontal arm extends from the top of the standard for carrying the pulley, so as to obviate a needless bend of the cable. The cable makes a sharp dip under the bridges, situated generally at the lower end of the locks, and is guided by pulleys placed against the abutments. The cable is guided round the curves by horizontal rollers placed near the ordinary pulleys. An engine of 30 HP. works a drum which draws along the cable; and special arrangements are provided for regulating the tension, and adjusting the length of the cable. The trials were carried on daily throughout last July with satisfactory results. Some estimates made by Mr. Maurice Lévy relative to a somewhat different system of rope haulage, established by him near Paris, indicate an economy of 58 per cent. with cable traction.

L. V. H.

Barrack-Arrangements on the Works for the Baltic Canal.
By - LÜTJOHANN.

(Deutsche Vierteljahrsschrift für öffentliche Gesundheitspflege, 1889, p. 577.) The arrangements made for the workpeople on the various large contracts now in course of execution in Northern Germany are briefly described by the Author. It would appear that, except under special circumstances, the unmarried labourers and navvies are compelled to reside in the barrack-huts erected for them on the works. These buildings have been carried out in accordance with prescribed regulations, among which stipulations are made for the provision of healthy dormitories, kitchens, and the necessary offices; a large room for meals and for Divine service; space for officials and for the post-office, and a special establishment for the charge of the sick. The latrines are to be placed so as to be immediately accessible to the living-rooms and dormitories, but must not be in contact with them; they must further be supplied with water. Each barrack was to be arranged in connection with a canteen, the purveyor being bound also to undertake the washing.

The Abstractor was present at one of the trials near Tergnier, on the occasion of the visit of the International Congress of the Utilization of River Waters, and can bear testimony to the ease with which a barge was attached to and released from the travelling cable, and the general satisfactory working of the system.