In the 1890s, lawyer and politician James Wickersham argued that pre-Columbian contact between Japanese sailors and Native Americans was highly probable, given that from the early 17th century to the mid-19th century several dozen Japanese ships are known to have been carried from Asia to North America along the powerful Kuroshio Currents. Japanese ships landed at places between the Aleutian Islands in the north and Mexico in the south, carrying a total of 293 people in the 23 cases where head-counts were given in historical records. In most cases, the Japanese sailors gradually made their way home on merchant vessels. In 1834, a dismasted, rudderless Japanese ship was wrecked near Cape Flattery in the Pacific Northwest. Three survivors of the ship were enslaved by Makahs for a period before being rescued by members of the Hudson's Bay Company. They were never able to return to their homeland due to Japan's isolationist policy at the time. Another Japanese ship went ashore in about 1850 near the mouth of the Columbia River, Wickersham writes, and the sailors were assimilated into the local Native American population. While admitting there is no definitive proof of pre-Columbian contact between Japanese and North Americans, Wickersham thought it implausible that such contacts as outlined above would have started only after Europeans arrived in North America and began documenting them.