Brakes not working?

I'm no expert.. That looks like a drum drum master cylinder because it has 2 equal reservoirs. Given the age of the car, raised paint from a brake fluid leak could be ghost of leak past.
If you have fluid leaks at the brake assemblies you'll find a mess on the backside of the wheel and tire.
I think I would just start pouring fluid at it. Pump the pedal until my leg is tired and walk away. If the fluid is all gone tomorrow morn the evidence is there somewhere. If fluid is still there I'd pump the pedal again and come back in the evening.
It will show the leak(s) eventually.