200 THE SCIENTIFIC PAPERS OF 



difficulty in the electric lamps of the present day, namely, the 

 carbon consumed ; for its re-adjustment required mechanism 

 which was not yet absolutely perfect, nor was the carbon absolutely 

 perfect. Great improvement had been made in the carbon rods, 

 and he had worked an electric lamp which for hours remained 

 almost absolutely steady ; but when the power varied, the im- 

 perfections of the carbon also showed themselves in an increased 

 degree. Mr. Shoolbred had alluded to a great many proposals for 

 overcoming the practical difficulties which now stood in the way 

 of making the electric light successful. There were two different 

 systems : the one with fixed carbons along with alternate currents, 

 of which the Jabloschkoff was a type, and the other with a con- 

 tinuous current. The reversed current had many advantages for 

 distributing and subdividing the light, whereas the fixed had the 

 advantage of being more economical. He considered that, in 

 resorting to reversed currents, and bringing the light down to the 

 position which gas lamps generally occupied, 60 to 70 per cent, of the 

 maximum effect was sacrificed, and the result was that the electric 

 light was expensive ; whereas if concentrated, and distributed over 

 a large area, it could be got cheaply. It was only for the engineer 

 who had the arrangement of it to make it face in such a way as 

 not to be inconvenient. He had heard a great deal about inven 

 tions for subdividing the electric light indefinitely, but he did not 

 attach so great an importance to that, as the electric light would 

 not take the place of gas for our streets or in our houses, though it 

 would come in largely for lighting halls and large public places of 

 every description ; but even if they could subdivide the light to 

 any extent, it would be found that such sub-division would reduce 

 the economy. As far as his experience went, it was rather a 

 question of concentrating than subdividing. 



