The Relative Value of Oil and Wine in the Talmud

For the last week I've been following Daf Yomi, the 7 year cycle by which Orthodox Jews read the entire Talmud. It's part of my "Echoes of Late Antiquity" hobby and so far I'm having fun. Take this translated quote from Sanhedrin 31a

If one witness attests [the loan of] a barrel of wine, and the other, of a barrel of oil: — such a case happened, and it was brought before R. Ammi, who ordered him [the defendant] to repay a barrel of
wine out of [the value of] the barrel of oil.

So a "barrel" of oil is worth more than the same of wine. That's nice to know. Of course, I'm relying on the translation from halakhah.com and that's always a worry.

FWIW, the legal principle here is that you need two witnesses. Since the value of the oil is higher, there are only two witnesses to the loan of the value of the barrel of wine.