Steam Boats protected from the Effects of Lightning. 107 
In order to ascertain how far the evolution of steam influenced the 
free passage of electricity, I constructed a small steam boiler, with 
two stop cocks placed at the distance of two or three inches apart 
on the top of the boiler. Just above, and on one side of one of the 
stop cocks, I placed a small brass ball, supported in its position by a 
stiff wire attached to the boiler. On filling the boiler half full of 
water, and placing it in a hot furnace, steam pretty highly condensed 
was made to escape through the cock, near the mouth of which was 
placed the brass ball. On charging a large Leyden jar until it emitted 
a spark of electricity, the size of a broom straw, and connecting the 
top of the jar by a small brass chain, which was fastened at its oppo- 
site end to another brass ball; this ball being held by the point of a 
rod, screwed into it, having a glass handle, and which was made to 
approach the one fixed to the boiler till they nearly touched, having 
a small stream of steam issuing between them; I found no electric 
spark whatever could be made to pass from one ball to the other 
however near they were approached, while steam continued to issue 
between them. Yet if the jar was discharged in any other direction 
than by the balls and through the steam, the spark, or shock would 
be almost sufficiently large to kill small animals, or to produce 
severe effects ona man. I found, on repeating the experiment, 
that it utterly failed to give a spark through steam in any direc- 
tion. That it could not be made to strike at any distance within 
the influence of steam. Neither could itbe made to strike the hot 
boiler. Nor could it be made to strike a red hot ball of iron; but 
as the ball cooled some, it would receive small sparks. A smooth 
polished metallic surface would also conduct it off without much 
noise. From the above experiments it may be concluded that steam 
is a powerful and ready conductor of electricity, so much so, that a 
small stream of it can instantly discharge a large Leyden jar, which 
is heavily charged, and that without the least apparent spark or noise. 
It is therefore pretty well proved, that the steam generated in a 
steam boat completely protects it from the effects of lightning. 'The 
electricity of the clouds, that would otherwise in many instances 
strike steam boats loaded with so much iron; on coming in contact 
with the moist and heated column of steam, which ascends above 
the boats, immediately diffuses itself through the volume of steam, 
and passes to the water without communicating any shock. Or in 
other words, the ascending ‘steam performs the office of a Franklin 
rod. ‘The steam being in such acase a much better conductor, than 
