snow? road salt? 
Earthquakes, mudslides, 4-hour traffic jams?
Cap, I had a 64 Plymouth Vailant. Single piston master cylinder. During the resto, the brakes were on the list, but I hadn't gotten to them yet as I was using it as my daily driver, also. I came around the corner, went to hit the brakes and they went right to the floor. There wasn't a proportioning valve, no second cylinder, just a very puckered &%$hole. Turns out that the line under the driver's door had burst. I had pushed the button for 1st gear (old mopar typewriter tranny) and was pulling the e-brake with both hands (old school pull/twist to unlock under the steering wheel style) Not an experience I wish to repeat.
