Rack Punch

Upon going home with Amelia from Chiswick Mall, Becky meets Amelia's wealthy brother Joseph, who is home from India. Becky recognizes him as a man of wealth and, though she is not attracted to him (Thackeray endlessly remarks on his corpulence and refers to him as "vain, selfish, lazy, and effeminate), plots to become his wife.

While at a party at Vauxhall, Jos requests a bowl of rack-punch and hilarity ensues. "That fat gourmand drank up the whole contents of the bowl" and disrupted the entire party with his attempts at singing and flirting, eventually becoming quite belligerent before being induced to leave by William Dobbin. The entire scene embarrasses Becky and puts an end to the courtship.

This incident causes the reader to question what exactly is rack-punch. According to this blog, it is a drink from India containing arrack (which is distilled from coconut sap), hot water, limes, sugar, and spice.