Lamp

Great! That's what we're here for! Yah, Jim!

Here's the way a rotary switch with 3 connections works. The hot lead is connected correctly but you've connected the neutral to the black screw. That's the screw that feeds power to the bottom light. When you turned the switch it shorted the hot to neutral causing the breaker to trip. It's a bit confusing but brass and black are usually if not always hot. A black wire in house wiring is hot, white is neutral. So if you connected the neutral (ribbed wire) to the nickel terminal the switch would work properly depending on the logic of the switch. I.E. ...Off - On (top lamp) - On (Both lamps) - On (bottom lamp) - Off. In some the 3rd position is omitted.

Good luck and a two terminal socket would be easier to deal with.

Thanks for the insights! The lamp is intended to be dimmable and I was using a dimmable bulb. That being said I don't need it to be dimmable and the original socket did only have the two screws. I'll try to find a socket with just the two terminals and try that.

It appears that the socket you selected may be intended for a lamp with a second bulb in its base and therefore it has more than the usual two screw terminals. Did the original socket have just two screw terminals? Are you intending to use the lamp with a single-filament bulb or with a two-filament bulb (low, med, hi)? If your original socket had just two screw terminals and the new socket has three, try to obtain a socket with just two screw terminals. The non-ribbed wire will have to go on the switched terminal, which is the one pictured closest to the screw shell lampholder.