W. P. Dexter on a Gas Lamp. 51 
that speed from place to place through these wires. Approach- 
ing the point of Dungeness the mariner sees an unusual] 
brilliant light, and from the noble phares of La Héve the same 
light flashes across the sea. These are Faraday’s sparks ex- 
alted by suitable machinery to sunlike splendor. At the present 
moment the Board of Trade and the Bretheren of the Trini 
House, as well as the Commissioners of Northern Lights, are 
contemplating the introduction of the magneto-electric light 
at numerous points upon our coasts ; and future generations 
will be able to refer to those guiding stars in answer to the 
amy What has been the practical use of the labors of 
araday ? But I would again emphatically say that his work 
. needs no such justification, and that if he had allowed his vis- 
ion to be disturbed by considerations regarding the practical 
; use of his discoveries, those discoveries would never have been 
made by him. “TI have rather,” he writes in 1831, “been de- 
sirous of discovering new facts and new relations dependent on 
magneto-electric induction, than of exalting the force of those 
already obtained ; being assured that the latter would find their 
fall development hereafter.” 
In 1817, when lecturing before a private society in London 
on the element chlorine, Faraday thus expresses himself with 
reference to this question of utility :—“ Before leaving this 
subject, I will point out the history of this substance, as an 
answer to those who are in the habit of saying to every new 
_ fact, ‘What is its use 2? Dr. Franklin says to such, ‘ What is 
the use of an infant 2? The answer of the experimentalist is, 
“Endeavor to make it useful.’ When Scheele discovered this 
substance it appeared to have no use; it was in its infancy and 
useless state, but having grown up to maturity, witness its 
_ powers, and see what endeavors to make it useful have done.” 
os 
3 
“ 
2 
Arr. VII.—Chemical Apparatus; by W. P. Dexter. 
Such a lamp may be made by removing the air 
on Bunsen lam ing in its place a 
lamp and putting in its place a 
