A gig was a small light carriage pulled by one horse. It was lit at night by two oil lamps with thick glass, called gig-lamps. These gave a double halo effect in the dark as it approached. Today some types of glasses can be called gig-lamps when they have very thick glass like the original lamps and I´ve seen the term used as slang for spectacles.
Hola a todos.¿Qué significa "gig-lamp" en el texto siguiente?: As I concluded, he stretched out a long, tremulous arm, and turned the gig-lamp in such a way as to throw a flood of light upon my face.