I went to the allotment today, collected some onions, looked at the frozen soil, and came home.
Never mind, here's one of my favourite coins. A moneyer's ass of Augustus, the first emperor. At 30mm and 9.73g, it's quite large and impressive. The ass was a fairly low value coin; two made a dupondius, which would buy a loaf of bread. A loaf, of course, was a glorified roll, big enough to provide a meal for one. It's called a 'moneyer's ass' because of the reverse inscription; M SALVIVS OTHO III VIR AAA FF SC. The letter 'U', of course, hadn't been invented, and 'V' did double duty. The big SC stands for 'Senatus consulto', 'By permission of the Senate', as that body was still technically responsible for the copper coinage. III VIR AAA FF means, more of less, 'Three Men for Gold, Silver and Copper'; these being the three officials responsible for the mint. it was an annual appointment, and apparently M Salvius Otho had the job in 7bc.
The obverse shows what is probably a thoroughly unlifelike portrait of Augustus, who was 56 at the time, with the inscription CAESAR AVGVST PONT MAX TRIBVNIC POT. This gives his two vital offices. The Pontifex Maximus, or High Priest (the title is still used by the Pope) controlled the religious system in Rome. He couldn't actually be a Tribune himself, as the office was restricted to Plebeians, and he was a Patrician, but Tribunicia Potestas, the power of a Tribune, gave him three things. His person was sacrosanct, or in other words, to harm him incurred the death penalty. He had the power to impose the death penalty. Above all, he had the power of veto, and could annul any law. This gave him effective control of the Senate. He allowed the appearance of power to remain with others, while jealously keeping the reality to himself.