A solution of glucose, sodium hydroxide, and indigo carmine, when shaken, will change from yellow to red to green. Left to sit, it will revert to red again, then yellow, and the process can be repeated.
The indigo carmine is green when oxidized, yellow when reduced, and red in the intermediate semiquinone state.
Puzzling tombstones, quoted in Grave Humor, Alonzo C. Hall, 1961:
Yorkshire, England:
Miles
This tombstone is a milestone. Why so?
Because beneath lies Miles. He’s Miles below.
A little man was he, a dwarf in size,
Yet now stretched out, at least Miles long he lies.
This grave, though small, contains a space so wide.
There’s Miles in breadth and length and room beside.
Sheffield, England:
John Knott
Here lies a man that was Knott born,
His father was Knott before him,
He lived Knott and did Knott die,
Yet underneath this stone doth lie.
London:
Ann Mann
Here lies Ann Mann,
Who lived an old maid
But died an old Mann
Dec. 8, 1767
The young Charles Lamb, visiting a churchyard with this sister, asked, “Mary, where are all the naughty people buried?”
Two trick questions:
Who played the title role in Bride of Frankenstein? Valerie Hobson — not Elsa Lanchester.
Did Adlai Stevenson ever win national office? Yes — Adlai Stevenson I served as vice president under Grover Cleveland in 1893.
On Thursday afternoon a large party of friends, who had been enjoying themselves at a picnic in the picturesque neighbourhood of Boscastle, Devonshire, were about to return home, when the hat of Mr. Dennis, a solicitor, who was assisting two ladies to the carriage, was blown off, and, in running hastily to recover it, the unfortunate gentleman fell over the cliffs, and was instantly dashed to pieces. The deceased gentleman was much respected.
— The Times, Sept. 1, 1853
We live the time that a match flickers; we pop the cork of a ginger-beer bottle, and the earthquake swallows us on the instant. Is it not odd, is it not incongruous, is it not, in the highest sense of human speech, incredible, that we should think so highly of the ginger-beer, and regard so little the devouring earthquake?
— Robert Louis Stevenson, “Aes Triplex,” 1878
By H. Van Beek, Chemnitzer Wochenschach, 1926 (special prize). White to mate in two moves.
The Russian navy undertook an odd experiment in 1871: circular warships. With their broad, flat bottoms, the Novgorod (above) and the Vice Admiral Popov (below) were intended to bear heavy guns into shallow coastal waters where more conventional warships could not go. But without keels they were slow and difficult to maneuver, and in cross currents they tended to spin. They served briefly in the Russo-Turkish War of 1877-78 but were relegated as storeships in 1903 and scrapped nine years later.
A tank of water has two holes of equal area, one at top and one at bottom. The top one leads to a downspout, so that both holes discharge their water at the same level. Ignoring friction, which hole produces the faster flow of water?
You actually don’t need to know the physics in order to solve this — it yields to an insight.
accubation
n. the act or posture of reclining on a couch
