When Svengali and Billie are having champagne at the café in Cairo, Svengali drains his glass. They exchange a few more words as Svengali is being introduced, then, when he stands, his glass is full again.
After Billie vows to follow Svengali and regain Trilby's attentions, there is an article in a Naples newspaper titled "Opera News." The second paragraph reads thus: "Monsieur Bonelli states Monsieur Svengali has recoved from his illness."
In the bathtub, Svengali says "Gott strafe England" ("God punish England"). This saying was created by German-Jewish poet Ernst Lissauer (1882-1937) during WWI. However, Svengali (1931) takes place during the mid-19th century.
In the opening scene, a late-19th-century pianoforte is shown, but a modern (1931) concert grand piano is heard.