. . .the tortuous, narrow streets of Jerusalem's Old City.
-- Lee Hockstader, "Pope's Road to Israel Paved by Past Errors", Washington Post, March 12, 2000
The attempts to substitute machines, methods of mass production, for the slow manual labour of antiquaries and historical researchers have all broken down; we still rely on those who spend their lives in painfully piecing together their knowledge from fragments of actual evidence, obeying this evidence wherever it leads them, however tortuous and unfamiliar the pattern, or with no consciousness of any pattern at all.
-- Isaiah Berlin, The Sense of Reality: Studies in Ideas and their History
Thus in the 1970s Terry Erwin of the Smithsonian Institution anaesthetized and then counted all the species of beetle in just one tree in Panama, perceived that the number of unknown species far outweighed the ones that had previously been identified, and through a sequence of reasoning that may seem a trifle tortuous but is widely agreed to be reasonable, calculated that the true number of all species on Earth is probably nearer to 30 million.
-- Colin Tudge, The Variety of Life
Tortuous is from Latin tortuosus, from tortus, "a twisting," from the past participle of torquere, "to twist."