Democritus was a man around 430 BCE. He was a ancient Greek philosipher and he lived in Greece. He worked on one question and that question was "What is stuff made of?" He assumed it was this thing called matter that was made of small pieces. These pieces were so small that they can't be broken or cut into anything smaller. He said that they are unable to get rid of and always will be there. Also hey said that they are constantly moving and that there is an infinite amount of these things that he named atomos, which means uncuttable, in the universe. Democritus realized that most likely the strongness of an object had something to do with the atom and how it was shapped. He made a drawing of what he assumed was what a atom looked like and it was basically a circle.
Rutherford:
Rutherford was a British-New Zealand scientist. He was a chemist and a physicist that is called the father of nuclear physics. He was a student of Thomson, another famous chemist and physicst, that discoverd that an atom has negatively charged things in an atom so assumed there must be a positively charged thing since atoms are neutral. Rutherford did this project called "Gold Foil" and you can read about this at http://en.wikipedia.org/wiki/Geiger%E2%80%93Marsden_experiment. At the end of this project of his he figured out that most of the mass is in the nucleus and that his teacher was wrong when he drew his model. He named the positivaly charged particles the proton. Rutherford also drew what he thought the atom looked like and that was something that looked like a "Peach Pit." It was a circle with a small circle in the middle (nucleus) and all these little electons on the outside.
Rutherford and Democritus:
Democritus and Rutherford are very different in the way they did things when trying to figure out things. Democritus was in 430 BCE and Rutherford was somewhere around 1911. So, there is a big difference between those years because equitment gets better and people begin to know more and more as the years go on. Yes, they both were chemist and physicist but they still did things differently. For one thing Democritus mostly assumed things after he looked up as much as he could find out Which wasn't much. He did this without doing many experiments while on the other hand Rutherford did experiments like the one I mentioned earlier named "Gold Foil." Also people came between these two men like Dalton and J.J. Thomson, who were very good at this stuff also, so what they found out was of use to Rutherford but not Democritus. This could have given Rutherford an extra advantage over Democritus but they were both really good at this kind of stuff. As you can clearly see these two men are alike and different in what they did and how they found out a lot of the things they did.
Rutherford
"Gold Foil"
Top: Expected results: alpha particles passing through the plum pudding model of the atom undisturbed.
Bottom: Observed results: a small portion of the particles were deflected, indicating a small, concentrated positive charge. Note that the image is not to scale, in reality the nucleus is vastly smaller than the electron shell.
"Gold Foil" picture and explanation is from http://en.wikipedia.org/wiki/Geiger%E2%80%93Marsden_experiment
Democritus:
