The third plan, instead of a wire, a metal tube is employed with a slit in the under side for the passage of a thin plate, attached to a shuttle which slides within the tube. Connection is made with the car by a flexible cord, as in the first plan. The advantages of this method are that there is no risk of the gatherer falling off, that it is out of sight, and there is less risk of sparking or flashing than in either of the other plans. Its disadvantages are increased cost, and a seven-eighths of an inch tube instead of a three-eighths wire.

The Moedling-Hinterbruehl line may be taken as typical of this class. M. Reckenzaun, in his paper before the Society of Arts, London, in 1887, gives the following description of it:—

"The conductors are made of slotted tubes in lengths of 15 feet each, and soldered together when placed in position. To prevent them from sagging stout wires are stretched over brackets on the tops of posts, and fastened to the tubes half way between the posts. The bore has to be made perfectly smooth and clean, so that neither mechanical nor electrical resistance is offered to the contact carriage sliding within; the actual diameters of the tube are 1 inch internally and 1ğ inches externally. The contact carriage consists of a flexible piece of flat steel upon which three gun-metal pistons are fastened; these pistons, which have to be renewed every two months, are made in two halves, with springs in the middle, whereby a slight pressure is produced between the surfaces in contact.

"The Moedling-Hinterbruehl tramway has been working successfully since 1884, at an average cost of 3·42d. per car mile, inclusive of every item of expense."

Separate special supports must be used for carrying the overhead conductors, for stringing cross wires from windows to house walls, from chimney-tops to lamp-posts, cannot be considered as permissible. When the streets are wide, forming broad avenues, with the tramway in the centre, leaving sufficient room for other carriages to pass each other between the tram-rail and the kerbstone, and the space occupied by the tram-rails is used almost exclusively by the cars, then, and only then, the best place for the poles or standards is in the centre of the road, between the two sets of rails, each

standard having an arm stretching right and left, and supporting a wire over the centre of either track. This is the very best arrangement where the width of street will permit it; but it is obvious that in ordinary streets the presence of a pole in the centre of the roadway every forty yards would be a serious hindrance to other traffic, and a prolific source of danger.

The safest place for the standards is on the kerbstone, and where the "slipper" or "shuttle" with the flexible cord are used, a short arm extending a few feet from the footpath is sufficient for supporting the wire or tube; but when the rubber and fishing-rod are employed, requiring the wire to be over the centre of the track, it is necessary to have the standards higher, and stretch wires across the street, hanging the electric conductor from them in the centre of the track; this produces a network of wire, and forms one of the objections against the system.

By the courtesy of a friend I am able to show you several photographs of overhead wire lines in America; he has also furnished me with the following statements, illustrative of the marvellously rapid progress made in that country.

Statement of American Electric Tramways.

On January 1, 1886, there were in the U.S.A., three experimental electric lines, aggregating 7 miles' track and 13 cars. March 1891, there are 319 electric tramways in operation. in 204 cities, and aggregating 2371 track miles and 3747

motor cars.

The largest equipments are West End Street Railway Company, Boston, 350 double motor cars, 65 miles of track equipped. This is to be extended to 230 miles, and power stations to contain the steam-engines and boilers for driving the generating dynamos to operate 1300 motor cars are now being constructed. Shareholders have authorized an expenditure of over £1,000,000.

Minneapolis and St Paul Street Railway has 100 electric cars in daily operation, and 100 more contracted for,-contract price £400,000.

Cleveland, Ohio, and St Louis, Missouri, have each 100 electric cars in daily operation.

Dynamos and motors representing 200,000 horse-power have already been sold for electric tramway work.

Statement of comparative test made in St Louis (ending Dec. 17, 1890) upon a cable and an electric line in that city operating under approximately the same conditions:

Though not for a moment wishing to see our streets disfigured by the rough and ready clumsy work too often permitted in the States, I can but express a hope that English prejudice will soon give way to utility and permit the use of some overhead system, regard, of course, being had to substantial work and neatness, if not elegance of design.

I venture to submit a design of a supporting standard for your criticism and, I hope, approval.

In the busiest thoroughfares of our large towns permission. to erect overhead wires for tramcar traction can hardly be expected, and recourse must be had to underground conductors.

Underground Conductors.

As far back as 1852, Mr Thomas Hall, of Boston, U.S.A., constructed a model of an electric car, using the rails as conductors, one conveying the current to the car, the other

returning it to the stationary battery. This may be described as the "come rail, go rail system," but attempts to employ it for street tramways have proved failures, because the rails, being electric conductors, were dangerous to the public, especially to horses with their iron shoes; and the rails being embedded in the earth, the electric leakage was so great as to make it practically inoperative for long distances.

As safety to the public is of first importance, the electric conductors must be out of harm's way, and to secure this an underground conduit is necessary, running the length of the line.

The conduits may be classified as closed and open.

The advantage of the closed conduit is that it dispenses with the slit in the surface of the road; many devices have been patented for this purpose, in all of them temporary communication is made between the electric conductor within the conduit and the section of the surface that lies immediately beneath the car.

This communication may be effected either by a little motor trolley running within the conduit-by mechanically or electrically actuating switches, or by magnetically attracting a strip or spiral that normally rests upon the enclosed conductors, but is raised to the surface as the car passes.

No tramways have yet been constructed with a closed conduit.

The largest demonstration hitherto made was in Paris, during the Railway Exhibition in 1887, when one of my patented systems was used and worked successfully, carrying a great number of passengers. I have pleasure in showing you a photograph of the car.

Open Conduits.--Many suggestions and experiments have been made for the employment of open conduits or channels with a slit or opening in the surface, but the first complete tramway made, viz., that at Blackpool in Lancashire, is the only successful one.

Before the construction of the Blackpool Electric Tramway many progressive experiments were made. They have been described and published in the technical papers, so it is unnecessary for me to refer to them at any length this

evening; but you will find upon the walls illustrations of the pleasure car and track employed at Moorside, Halifax, and of the full-sized car that ran in a field near Manchester. The Moorside track is illustrated in fig. 9 and the Manchester track in fig. 10.

As previously stated, the first electric tramway constructed having a channel with a slit or opening in its surface is that at Blackpool in Lancashire. It is the only successful one in existence.