opper wire to the zinc of the next glass, and each transmits the electric current derived from the chemical action in its own glass, in addition to that derived from the action in the preceding glasses.
The trough-battery c c′ was used by Sir Humphry Davy in his series of magnificent discoveries, 1806-8, when he isolated the metallic bases, calcium, sodium, potassium, etc. His trough had 2,000 double plates of copper and zinc, each having a surface of 32 square inches.
It is like the compomospheres, and cold water be passed through the other receiver, the latter will exert a force of from 40 to 50 atmospheres.
The difference in the pressures, say 45 atmospheres to the square inch, will be the power on the piston (at the start).
Davy and Faraday, about 1823, succeeded in reducing several gases to a liquid state by means of great pressure and very low temperature.
Upon releasing the pressure, the gases were found to again expand to their original volume.
This discovery again