Miscellanies. 355 
within the receiver, and does not consequently apply to the pumps 
with metallic valves. It is not supposed that a person who should 
purchase a new pump, would obtain one of the common kind and 
have the “improved receiver’ of Mr. Bell attached to it; but while 
he has in his possession an instrument of the former kind, he may 
render it equal in the effects produced, to those with metallic valves, 
by attaching to it the receiver of Mr. Bell. It is not supposed or 
intended that the above receiver should be used in performing the 
common air pump experiments, that require only a partial vacuum, 
but that it should be confined to those where a more perfect one is 
necessary. 
MISCELLANIES. 
FCREIGN AND DOMESTIC. 
1. Oxy-hydrogen illumination. C. U.S.—M. Jose Roura, Pro- 
fessor of Chemistry in the University of Barcelona, sent a letter to 
the Royal Academy of Paris, suggesting an improvement in the 
oxy-hydrogen illumination of Capt. Drummonp, by substituting the 
sulphate of lime for the carbonate ; the former is powdered, mixed 
into a paste with some gum, and then cut into small pieces; the jet 
of oxygen and hydrogen upon it produces a most brilliant light, sul- 
phurous acid and water are disengaged, and oxide of calcium re- 
mains. M. Araco observed that the French light-house commis- 
sion were engaged in effecting a similar plan of illumination; after 
some experience, it was proved that the light emitted was equal to 
that of twenty thousand Argand lamps, but this intensity is not con- 
stant, because the heat soon hardened the lime so as to require fre- 
quent removal or snuffing, to allow the flame to operate upon the 
fresh particles ; another inconvenience is, that the light produced by 
a lumimous body of such small dimensions as a cylinder of lime can 
have but a very slight divergence, and when upon the horizon, its 
appearance at each point from a revolving light would be almost in- 
stantaneous, so that navigators may fail m perceiving it, and be un- 
able to discover the situation of the light house.-—Atheneum, Nov. 
2. Singular preservation of Life in a Molluscous Animal... 
Rane, Member of the Royal Academy of Sciences of Paris receiv- 
