SIR WILLIAM SIEMENS, F.R.S. 259 



houses, the amount of which I have not been able to ascertain 

 accurately, but it may safely be taken at two-thirds of the cost of 

 coal for the engine, thus reducing the cost of the fuel per light to 

 \il. i>erhour; the total cost per light of 5000 candles will thus 

 amount to Gd. plus Id., equal to Id. per hour. 



This calculation would hold good if the electric light and 

 engine power were required during, say, twelve hours per diem, 

 but inasmuch as the light is not required during the day-time, 

 and the firing of the boiler has nevertheless to be kept up in 

 order to supply heat to the greenhouses, it appears that during 

 the day-time an amount of motive power is lost equal to that 

 employed during the night. In order to utilise this power I have 

 devised means of working the dynamo machine also during the 

 day-time, and of transmitting the electric energy thus produced 

 by means of wires to different points of the farm where such 

 operations as chaff-cutting, swede-slicing, timber-sawing, and 

 water-pumping have to be performed. These objects are accom- 

 plished by means of small dynamo machines, placed at the points 

 where power is required for these various purposes, and which 

 are in metallic connection with the current-generating dynamo 

 machine near the engine. The connecting wires employed consist 

 each of a naked strand of copper wire, supported on wooden 

 poles, or on trees, without the use of insulators, while the return 

 circuit is effected through the park railing or wire fencing of the 

 place, which is connected with both transmitting and working 

 machines, by means of short pieces of connecting wire. In order 

 to ensure the metallic continuity of the wire fencing, care has to 

 be taken wherever there are gates to solder a piece of wire buried 

 below the gate to the wire fencing on either side. 



As regards pumping the water, a 3 horse-power steam engine 

 was originally used, working two force-pumps, of 3 inches 

 diameter, making 36 double strokes per minute. The same 

 pumps are still employed, being now worked by a dynamo machine 

 weighing 4 cwt. When the cisterns at the house, the gardens, 

 and the farm require filling, the pumps are started by simply 

 turning the commutator at the engine station, and in like manner 

 the mechanical operations of the farm already referred to are 

 accomplished by one and the same prime mover. 



It would be difficult in this instance to state accurately the 



s 2 



