Penetration
of Canal Rays into Solids. J. STARK and G. WENDT.
(AM. d. Physik., xxxviii, g21.)-Several pages are occupied in stating the problem and in its theoretical consideration, and sketches of the apparatus are given. Hydrogen canal rays of cathode-fall LIP to 5000 volts scatter the smooth surfaces of calcspar, Ruorspar, glass, and quartz ; but they do not destroy the polish. Plates of rock-salt, sylvine, and mica are perceptibly roughened by :he impact of slow canal rays.
Canal rays of kathode-fall greater ban 10,000 volts roughen the surface o'f fluorspar, calcspar, glass, ;ylvine, mica, and rock-salt.
Thle surface of quartz is not roughened, vet there is considerable scattering.
With calcspar mercury canal -ays produce a chemical change in the surface, due to the hleating #ect; they also produce a scattering effect in all the substances submitted to experiment, without causing a roughening of the surface at the po'int of impact.
The mechanical deep action of the lydro'gen canal rays cannot be ascribed to the penetration of the rays :hrough the inter-molecular valency fields under the surface layer. solid metals are dulled by slow hydrogen canal rays through scatterng. The surface of the base of a bismuth crystal is not perceptibly .oughened bv slo'w canal rays, and only very slightly by rapid rays ;
.he rays have a much greater scattering effect upon a surface shose plane is approximately perpendicular to this direction.