Mk. Glassford on the Electric Light. 23 



for the express pui-pose of showing the electric light, and for testing its 

 applicability to the purposes of ordinary life. Mr. Glassford described 

 the different schemes which had been tried by Mr. Staite, the patentee of 

 the electric light, to render this brilliant source of light available for the 

 ordinary purposes of illumination. It is well known that a most intense and 

 beautiful light is emitted when pieces of wood charcoal, connected to the 

 poles of a large battery, are brought in contact and then slightly with- 

 drawn from each other. This, until within the last few years, was the only 

 method known and practised for showing the electric light. From the 

 great combustibility of the charcoal points, they were quickly consumed, 

 and of coiu-se the light was extinguished. The luminous power of the 

 galvanic fluid was known as early as 1810, and many experiments were 

 made with the large battery of the Royal Institution, London, and the 

 illuminating phenomena produced were of the most brilliant and dazzling 

 description. 



That such a splendid light might be made available in ordinary life, 

 doubtless suggested itself to many, and numerous trials were probably 

 made with this view. But it appears that M. Achereau of Paris was the 

 first who really succeeded in keeping up a constant light, and in actually 

 applying it to ordinary illtiminating purposes. This was done in 1843, at 

 the Place de la Concorde in Paris, but the trial, although eminently 

 successful in demonstrating its practicability, had no further result, and 

 for a long time it seems to have been lost sight of. Mr. Staite has again 

 brought the subject before the world, and has patented an ingenious 

 apparatus, whereby the light can be regulated by the same means that the 

 light is produced. He has also introduced more suitable materials than 

 wood-charcoal as electrodes, or light-conducting points ; and has appar- 

 ently almost overcome the mechanical difficulties in practically applying 

 electricity to the purpose of illumination. The machinery employed for 

 producing the various upward, downward, and horizontal motions, is an 

 adaptation of clock machinery, and the motive power is obtained by 

 magnetising a bar of soft iron with a current of the electricity while on its 

 way to the points of illamination. Instantly the current of electricity is 

 established, the bar of iron — round which, in a circle of small wire, the 

 current flows — becomes magnetic, and attracts a small piece of iron in its 

 immediate vicinity, which is attached to one of the small clock wheels. 

 The instant the smaller bar of iron moves, the whole machinery is set in 

 motion, and the electrodes, or tubes holding the illmninating points, are 

 drawn asunder. The electric fluid now traverses a stratum of air, and 

 sheds its intense and dazzling light, and in proportion to the power of the 

 battery, so is the distance of these electrodes from each other, and so is 

 the volume of light great or small. If the points are drawn too far apart, 

 the current will suddenly cease, and the light disappear. On this the 

 small bar of iron, before under the uifluence of magnetism, loses its power 

 and falls into its former position ; in consequence of which the motion of 

 the machinery is reversed, and now the illuminating points arc rapidly 



