Classic/Antique Car Repair: 61 Rolls brakes, master cylinders, braking system

Question
I have a '61 rolls that has sat for more than a year and what had been good brakes no longer work. It seems i can get them to engage once but they don't reset and the pedal doesn't return. We have had others not familiar with these brakes look at the situation but they were clueless.

Answer
If you are in Florida I can be of service. to try to diagnose this issue over the net is difficult and possibly dangerous, but lets get a few things sorted clear. first of is there fluid in both reservoirs? the pedal not returning is an indication of severe corrosion in the master cylinders, has the fluid been changed every two years as required? How many miles are on the car. and how long ago was the entire braking system been serviced or refitted?