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 incontestably true, contrary to what some people have supposed, that they were unable to perform this illusion in the way we have described, for they were ignorant of the method of manufacturing and polishing glass plates of sufficient size and clearness for the purpose.

The production of living but impalpable spectres is thus a completely modern achievement, as we have already proved, and which has taken its place amongst the applications of science to stage art, to the total exclusion. of all effects depending for their production on the old-fashioned phantasmagoria and magic lantern.