How Did We Discover These Protons?

ideas about atomic structure were already in place by the time Rutherford had made his experiments, which was in 1919. This was actually just proof that protons exist point and the nucleus, you know, is a thing. Yeah, Rutherford did some pretty cool stuff otherwise as well in particle physics. One of the big things he did was nuclear fusion. It's kind of funny that he split the atom, but he didn't discover nuclear fission. Someone else didn't took to know that either.