Short Papers and Notes. 49 
resembles, and might be substituted for, citronelle oil, so exten- 
sively used for scenting soap. 
Prof. Tyndall on the Electric Light. 
An interesting lecture was recently delivered by Professor 
Tyndall on the above subject. Beginning with the discovery of 
Volta, he explained the principles of galvanic decomposition and 
resistance to the electric current, and stated the part which Davy 
took in demonstrating the importance of Volta’s discovery. A 
fresh step was taken in 1831, when Faraday discovered magneto- 
electric induction. From this time the work was carried on by 
Holmes, the Alliance Company of Paris, M. Gramme, Dr. 
Siemens, and Sir C. Wheatstone (who made an important dis- 
covery simultaneously), and a number of inventors whose names 
had been recently before the public. [The several machines 
made up to late times were described, a multitude of experiments 
was made by the lecturer, assisted by Mr. Cottrell, and various 
modes of electric lighting were exhibited. Mr. De Meritens 
showed his electric candle of three carbons, the current being 
generated by one of his machines, which Professor Tyndall said 
he trusted would put inventors on their mettle. Mr. Ladd showed 
the Wallace-Farmer machine, and illustrated the brilliant effect of 
the incandescence of iridium. M. Rapieff showed his lamp, as 
now used in a newspaper office. The Jablochoff candle was also 
exhibited, a Siemen’s lamp hung from the roof, and Mr. Werder- 
mann’s light was fitted up in an adjoining room. | 
In conclusion, the lecturer said he would not then go into the 
questions of the division of the electric current and incandes- 
cence. All the laws of the subject he had been dealing with 
were known, and there was no room for a discovery in the scienti- 
fic sense, but there was room for the application of such mechani- 
cal ingenuity as had given us the sewing machine, the phono- 
graph, and many other things. The investigator and discoverer 
pursued his theme for the sake of gaining knowledge; the 
inventor’s aim was generally to make money, though he gladly 
recognised that in many cases the inventor was stimulated by love 
of his art. Sometimes these men spoke disrespectfully of each 
other, as Cuvier despised the man of practical application, pro- 
bably not taking into account that the application of science 
reacted on science. The amelioration of the condition of the 
community was, at any rate, an object worth labouring for. Still, 
it was well to remember that those discoveries and applications 
which struck the public mind and excited so much discussion, 
often come from men whose sole stimulus was an intellectual one. 
As to the philosophic aspect of the question, there was a small 
Vol. WOE 3—3 
