Please answer a question about the following article about Tuvalu:

Trading companies became active in Tuvalu in the mid-19th century; the trading companies engaged palagi traders who lived on the islands. John (also known as Jack) O'Brien was the first European to settle in Tuvalu, he became a trader on Funafuti in the 1850s. He married Salai, the daughter of the paramount chief of Funafuti. Louis Becke, who later found success as a writer, was a trader on Nanumanga from April 1880 until the trading-station was destroyed later that year in a cyclone. He then became a trader on Nukufetau.

In what century did trading companies arrive in Tuvalu?
mid-19th