'At the bottom of the Encarta article on this device are links to "optics" & "submarine"'
Periscope
OPTICS: At the bottom of the Encarta article on this device are links to optics & submarine
At the bottom of the Encarta article on this device are links to "optics" & "submarine"
At the bottom of the Encarta article on this device are links to "optics" & "submarine"
OPTICS
Periscope
OPTICS