I have been trying to understand pascal's barrel experiment in a more qualitative sense but I can't get my head around it at all. Pascal supposedly had a strong wooden barrel which he attached onto it a very thin pipe which was 20m tall. He then poured water into the top of the pipe until both the barrel and pipe were filled. The outcome of the experiment was that the barrel burst due to the pressure generated by the pipe. If the pipe was 20m high then this would generate 20m of hydrostatic pressure apparently?! How does this work? I know quantitatively that it needs to work as there is no volume term in the pressure equation (P = ρgh). How can such a tiny mass of liquid exert so much pressure? Apparently the pipe was only 0.4cm wide! It almost seems like your getting a huge amount of pressure from almost nothing. If anybody can help explain how this experiment works that would be great!