A 1960's camping lantern I found at a local charity shop for £6 with broken battery compartment, I thought if I could find the voltage, I could wire it through a transformer into the mains and make into a bedside reading lamp.
Inspect the wares, work out how you haven't actually bought a bargain but a thoroughly broken, used, shell of a lamp with a bulb in it.
Unscrew switch bay and remove lenses.
Find what wattage the lamp is, in this instance I found it to be six. Then acquire a transformer from your local radio shack or in my in my case a maplins.
Set it to six.
Cut, split and strip the ends.
Drill a hole in the back of the tin casing big enough to fit both sides of cable through, I used 6 mm.
Take one of the cables, as seen here the white one and solder then electrical tape onto the spring tab of the switch.
Post the other side of you power cable through the pre-drilled holes in the other side of the lamp into the lamp reflector casing.