Sonic disc

Sonic disks(this is possibly not their true name) were sonic weapons devised by the Sea Devils during the time they ruled the Earth with the Silurians. They served as a kind of heat ray, capable of scorching ships and sinking them.

The Sea Devils used them when they awoke in 1972 and again in 2084. They also possessed a larger cutting device for cutting through doors. (DW: The Sea Devils, Warriors of the Deep)