Roman Taxes, Restriction Enzyme Etymology, and Collapsed Lungs

Today I Learned:
1) The Roman Republic (this was Rome before Julius Ceasar) collected taxes using private contractors. These contractors would bid on how much money they would supply the government using tax money from some province or another. I gather that this was something of a gamble, because it was hard to tell exactly how much tax would be collectable from a province until someone actually went out and did it. The winning contractor would then loan their bid to Rome, go out and collect whatever taxes they could, and return. The contractor would give whatever they bid to Rome, Rome would pay back the initial loan, plus some interest, and any tax money collected in excess of the bid would be kept by the contractor.

2) Restriction enzymes (enzymes that cut DNA at (usually) specific sequences) are called restriction enzymes because they were first discovered as enzymes that "restricted" the growth of lambda phage in E. coli. Yet another poorly-named biology term.

3) How a collapsed lung works. Er, doesn't work. Anyway, there's apparently a membrane covering the outside of a lung which attaches the alveoli in the lung to the musculature that controls breathing. If the lung detaches from that membrane, it collapses and sticks to itself like a wet plastic bag, and the body can't pull the lung apart.