Electricity for public schools and colleges . n a horizontal axis that lies parallel to theline of the three sparks a b, c d, and cf. Above it is a horizontal screen of ground glass, marked out indegrees in a manner indicated later on. The mirror can be made to revolve rapidly, its rate of revolu-tion being indicated by clockwork or by the musical note producedby its striking a fine metal wire. If the discharges take place very rapidly, then a person lookingdown from above will see some of the sparks reflected in themirror as it passes through the position proper for reflection of thesparks to
Electricity for public schools and colleges . n a horizontal axis that lies parallel to theline of the three sparks a b, c d, and cf. Above it is a horizontal screen of ground glass, marked out indegrees in a manner indicated later on. The mirror can be made to revolve rapidly, its rate of revolu-tion being indicated by clockwork or by the musical note producedby its striking a fine metal wire. If the discharges take place very rapidly, then a person lookingdown from above will see some of the sparks reflected in themirror as it passes through the position proper for reflection of thesparks to the eye ; others of the sparks will not be seen, owing tothe mirror being unsuitably situated at the moment of theiroccurrence. The rotation of the mirror will of course distort, by drawingout in the direction of the motion any spark that lasts anappreciable time ; that lasts while the mirror has movedappreciably. Now it is found that, for moderate rates of revolution of themirror, we see on the screen X Y merely three points of light,.
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Keywords: ., bookcentury1800, bookdecade1890, bookpubl, booksubjectelectricity
