Spiegazione della donna invisibile del sig. Rouy con figure
A short Italian pamphlet published in Milan in 1808 by Giovanni Silvestri, explaining how Monsieur Rouy's "invisible woman" speaking-sphere illusion worked, aimed at curious theatre-goers and amateur conjurors. The engraved plate gives numbered cutaway diagrams: a hollow globe slung in a four-post frame, concealed speaking tubes, a hidden operator in a partitioned room, useful as period technical line work and secret-mechanism imagery.
