Prof. Draper's Descrip he Tithonometer. 219 
When, on the sentient tube tithonometer, the image of 
true result. By the inte Scition of alens this heat is absorbed, 
and the tithonic raysg b 4 One act. 
Said & 
be passed so rapidly that the instrument will fail to give the 
proper indication. 
The experimenter may further assure himself of the extreme 
sensitiveness of this mixture by placing the instrument before a 
window, and endeavoring to remove and replace its screen so 
quickly that it shall fail to give any indication; he will find that 
it cannot be done. 
_ Charge a Leyden phial, and place the tithonometer at a little 
distance from it, keeping the eye steadily fixed on the scale; 
discharge the jar, and the rays from the spark will be seen to ex- 
ert a very powerful effect, the movement taking place and ceas- 
ing in an instant. 
This remarkable experiment not only serves to prove the sensi- 
tiveness of the tithonometer, but also brings before us new views 
of the powers of that extraordinary agent, electricity. ‘That en- 
ergetic chemical effects can thus be produced at a distance by an 
electric spark in its momentary passage, effects which are of a 
totally different kind from the common manifestations of electri- 
city, is thus proved; these phenomena being distinct from those 
of induction or molecular movements taking place in the line of 
discharge, they are of a radiant character, and due to the emission 
of tithonicity ; and we are led at once to infer that the well known 
changes brought about by passing an electric spark through gase- 
ous mixtures, as when oxygen and hydrogen are combined into 
water, or chlorine and hydrogen into muriatic acid, arise froma 
very different cause than those condensations and percussions by 
which they are often explained, a cause far more purely chemical 
in its kind. If chlorine and hydrogen can be made to unite si- 
lently by an electric spark passing outside the vessel which con- 
