Pressel.
A press-button often contained in a pear-shaped handle, arranged for
attachment to the end of a flexible conductor, so as to hang thereby. By
pressing the button a bell may be rung, or a distant lamp may be
lighted.
Pressure.
Force or stress exerted directly against any surface. Its dimensions are
force/area or ((M*L)/(T^2)) / (L^2) = M/(L* (T^2)).
Pressure, Electric.
Electro-motive force or potential difference; voltage. An expression of
metaphorical nature, as the term is not accurate.
Pressure, Electrification by.
A crystal of Iceland spar (calcium carbonate) pressed between the
fingers becomes positively electrified and remains so for some time.
Other minerals act in a similar way. Dissimilar substances pressed
together and suddenly separated carry off opposite charges. This is
really contact action, not pressure action.
Primary.
A term used to designate the inducing coil in an induction coil or
transformer; it is probably an abbreviation for primary coil.
Primary Battery.
A voltaic cell or battery generating electric energy by direct
consumption of material, and not regenerated by an electrolytic process.
The ordinary voltaic cell or galvanic battery is a primary battery.
Prime. vb.
To impart the first charge to one of the armatures of a Holtz or other
influence machine.
Fig. 273. PRIME CONDUCTOR AND PROOF PLANE.