The Encyclopedia Americana (1920)/Roric figures

RORIC FIGURES (Fr. figures roriques, from Lat. ros, dew), a name applied to certain curious images rendered manifest upon breathing on polished solid surfaces, when these have been previously exposed to contact or close proximity of the objects thus represented, and at the same time have been acted upon by light, heat or electricity. The singularity of these phenomena is, that they consist usually in the production at the first of a sort of latent or invisible image, but this may afterward be developed or brought out, somewhat in the manner of photography. Consult Chwolson, O. D., ‘Lehrbuch der Physik’ (1902).