Meaning of Wood's metal

Wood's' met'al

Pronunciation: [key]
— Trademark. Trademark.
  1. a fusible alloy of 50 percent bismuth, 25 percent lead, 12.5 percent tin, and 12.5 percent cadmium; melts at 158°F (70°C): used in the valves of sprinkler systems.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.