Here is a Hamilton not seen too often a grade 952 that is pendant set

the dial

Samie, I've yet to own a Hamilton bridge movement. How many pieces does the upper "plate" break down into?

It looks like there could be as many as four individual pieces: balance cock, escape and 4th wheel, center train, and the barrel/crown bridge.

Yes Eric you have it right these are what called a true bridge movement .One bridge cover 4th and escape wheels ,,one covers the 3rd and center wheel then you have barrel cover and balance cock t..these are a joy too service the plates fall in place when you are putting it back together.