Joseph Bramah, a later scientist (1748-1814), put this theory into practical use, when he found that force applied in a small piston produced a greater force in a larger piston, but with less movement.
A great way to experience this is to fill and put two different sized syringes or pistons together and press one at a time. It is easy to push the water from a small piston into a larger one, but much harder the other way!
Take out some pistons and try it!