notably a tramway from Portrush to Bushnells, near the Giant's Causeway, in the north of Ireland, and a line under the Thames from Charing Cross to Waterloo. It has also been proposed to carry letters by underground post on this plan, and the suggestion is a good one, for the distance traversed may be far greater than by the pneumatic despatches now in vogue. In Paris an electric railway has been projected along the boulevards, and we also learn that an electric tramway has been introduced into the bleachfields of the Breuil-enAuge (Calvados), France, where it transports the linen to the grounds with a cleanliness which could not be obtained with steam-power. As another application of electric power it should also be mentioned that the same dynamo which pulls the waggons full of linen is also used to turn the reels which wind and unwind the webs of cloth as they are spread upon or lifted from the grass.

The electric power in the case of the Bleachfield Tramway is not sent along the rails from the generator direct, but is derived at second-hand from sixty Faure secondary batteries or accumulators, carried by the tender of the train. This mode of "storing" the electric current will be serviceable in the case of street tramcars and omnibuses, which cannot very well have the electricity sent to them by special conductors. They will have to preserve their independence of action by taking their own supply of power with them, and the Faure or the Sellon accumulators will enable them to do so. Twenty accumulators freshly charged at the terminal station by a dynamo-electric generator will enable an omnibus or tramcar to run a whole halfday, and the exhausted accumulators can be readily

replaced by charged ones or themselves charged afresh.

Boats, tricyles, and even balloons can be supplied with power in the same way, but as yet very little has been accomplished in this direction, if we except the trials made by M. Trouvé, of Paris, in his boat on the Seine, and the toy balloon exhibited by M. Tissandier at the recent Paris Electrical Exhibition. In both these instances the power was derived from batteries, and the propeller of the vehicle was driven by a Trouvé electric motor.

Figure 76 shows the arrangement adopted by M. Trouvé to drive his boat. There we have a small Trouvé motor, consisting of two electro-magnets forming a frame enclosing a Siemens bobbin of wire which rotates between the poles of the magnets when a current is passed through it by connecting wires. The rotation of the bobbin is communicated by proper gearing and a cord to a pulley which is fixed on the shaft of the propeller or screw. This propeller is carried by the rudder, which is cut so as to admit it. Fitted with this apparatus, and deriving its motive power from a battery of 12 large elements, M. Trouvé's little craft The Telephone sped up the Seine on the 26th of May, 1881, against the tide at the rate of 3 miles per hour. The boat was about 18 feet long by 3 feet 6 inches wide and carried three persons. The total weight of the motor and batteries was about 64 lbs.

As long ago as 1839 M. Jacobi, the famous Russian electrician, made a trip on the Neva in a boat propelled by the current from a battery of 128 Grove cells, actuating a peculiar motor of his own device. The

boat was urged by paddles and ascended the Neva with twelve passengers on board. So powerful was the electric current from the battery that it heated white

hot 6 feet of platinum wire as thick as a darning needle; but though the speed was satisfactory the fumes from the acid battery rendered the voyage anything but pleasant.

The latest achievement in this line was the trial trip of the E. S. Electricity (to coin an abbreviation for "electric ship") from the works of the "Electrical Power Storage Company" of Millwall to London Bridge and back on September 28, 1882. This electric launch is 25 feet long by 5 feet across the beam, and draws about 2 feet of water. She was propelled by a 22 inch screw driven by a Siemens dynamo, which was actuated by the current from 45 accumulators of the SellonVolckmar type. These reservoirs of electricity were stored in different parts of the vessel and served as ballast. They were charged with electricity before starting and were capable of furnishing 4 horse-power of energy during a period of six hours. Two Siemens dynamos were taken, and either or both could be driven by the current at will. The rotation of the Siemens bobbin was communicated by proper gearing to the shaft of the propeller.

With four persons on board the Electricity made the course from Millwall to London Bridge and back, in spite of wind and tide, in 24 minutes; calculation shows that this effort corresponded to an expenditure of over 3 horse-power during the time; but it would have been more satisfactory had the voyage lasted longer, in order to test the staying powers of the accumulators. The singular appearance of the craft shooting along as if self-impelled and emitting neither smoke nor noise, attracted much attention. On pleasaunce waters, such as the upper reaches of the Thames, a quiet vessel of this kind would be preferable to the fussy little launches which infest them.

The electric plough promises well as an application of the transmission of power by electricity. It has an

advantage over the steam-plough in that no fuel has to be transported at great expense in horses from the farm-yard to the field where the steam-engine is stationed; for the engine can work at the yard itself, or it may be at the coal-pit mouth, and its power can be transmitted by wire to the distant field where the plough is working. The plough itself need not differ from the ordinary steam-plough with one or more shares, which is pulled by ropes from one end of the furrow to the other; and the only change necessary is in the stationary winches or drums which wind and unwind the ropes pulling the plough. These winches are fitted, as in the ploughs of M. Felix, with dynamo-electric motors, through the bobbins of which the current is passed. The rotation thus produced is communicated to the drums by proper gearing.

There are many other uses for electric power, some of which have been already tried, others only thought about. The Siemens electric lift, for example, was operating day after day in the Paris Electrical Exhibition: so also was the electric hoist of Dr. J. Hopkinson.

In the electric lift, the cage, supported by two ropes, is raised or lowered by means of a toothed pinion working into a kind of rack or ladder. The pinion is turned by a Siemens dynamo, carried in a box beneath the cage, and deriving its current by wires from a stationary generator.

In the electric hoist, the chains carrying the weight to be lifted are wound and unwound on a drum or pulley by a dynamo attached to the latter, and the reversal of the current reverses the motion of the pulley