Half a cartload of fish was stored in wooden barrels, all of the large variety. When Su Yunjin hired the ox cart, she had made a deal with the driver, offering the driver a few extra copper coins.
When she got off, the driver helped her move all the fish from the cart.
Earning some silver, the driver naturally wouldn't refuse, and was quite happy to agree to Su Yunjin's request. Su Yunjin instructed the driver to carry all the barrels to the kitchen. Following Su Yunjin's orders, the driver moved the barrels of fish one by one from the cart into Su Yunjin's kitchen.
After he finished, the driver dusted off his clothes and, smiling, approached Su Yunjin, "Miss, it's done. I've moved all your fish!"
"Uncle, thank you for your trouble." With that, Su Yunjin took out the copper coins she had prepared in advance and paid the man. The man counted the coins, saw there was no shortage, then took the money and left with his ox cart.