Tiny Point Roberts, Wash., is built on a finger of land that extends south of the 49th parallel into Boundary Bay. This means that, though it’s part of the mainland United States, it can be reached by land only by traveling through Canada.

Similarly, Minnesota’s Northwest Angle extends from Manitoba into the Lake of the Woods, and Alburgh, Vt., resides on a peninsula that extends south from Quebec into Lake Champlain.

None of these places are islands; all are part of the 48 contiguous states but are not directly connected to them by land. Among other things, this makes life difficult for students in Point Roberts, whose primary school offers classes only through third grade. From fourth grade on, students must take a 40-minute bus ride through British Columbia to attend classes in Blaine, Wash.

When Chinese herbalist Li Ching-Yun died in 1933, newspapers were hard pressed to write his obituary. Li had contended that he had been born in 1736, which would have made him 197 years old.

In 1930, Wu Chung-Chien of Minkuo University had reported finding records showing that Li had been even older, born in 1677 and congratulated by the imperial Chinese government on his 150th and 200th birthdays.

In 1928 a correspondent to the New York Times had reported that the oldest men in Li’s neighborhood insisted that their grandfathers had known Li when they were children and that he was then a grown man.

Tales told in his province held that Li had traveled widely during his first century, gathering herbs to sell, but then had switched to selling herbs gathered by others. He told one pupil that the secret of living to 250 was to “keep a quiet heart, sit like a tortoise, walk sprightly like a pigeon, and sleep like a dog.” He was credited with either 14 or 23 wives; one 1928 account said that he had 180 living descendants.

He was certainly well preserved. The New York Times noted drily that, according to its 1928 report, “many who have seen him recently declare that his facial appearance is no different from that of persons two centuries his junior.”

(Thanks, Francisco.)

Two billion years ago, in what is now Gabon in West Africa, groundwater seeped through sandstone to inundate a layer of uranium ore, initiating a nuclear chain reaction. When the deposit heated up, the water boiled away, slowing the reaction; when it cooled, the water returned and the cycle began again.

The result was a natural, self-sustaining nuclear reactor that generated 100 kilowatts of power for several hundred thousand years.

French physicist Francis Perrin discovered the phenomenon at Oklo in 1972. “As far as we know, we only have evidence of natural reactors forming and operating at the one site in Gabon,” said Jay Cullen of the University of Victoria, “but that demonstrates that it’s possible, and our calculations suggest it was much more probable earlier in Earth’s history.”