Howard C. Saar of Albion, Mich., pointed out an innovative solution to this problem in Recreational Mathematics Magazine, April 1962:
log(3x + 2) + log(4x – 1) = 2log11
Divide each side of the equation by the word “log”:
(3x + 2) + (4x – 1) = (2)(11)
7x = 21
x = 3
… which is correct.
Claude Shannon, the father of information theory, took an active interest in juggling. He used to juggle balls while riding a unicycle through the halls of Bell Laboratories, and he built the first juggling robot from an Erector set in the 1970s. (The machine above mimics W.C. Fields, who himself juggled in vaudeville before turning to comedy.)
Noting that juggling seems to appeal to mathematics-minded people, Shannon offered the following theorem:
F is flight time, the time the ball spends in the air
D is “dwell time,” the time it spends in the hand
V is vacancy, the time a hand spends empty
B is the number of balls
H is the number of hands
“Theorem 1 allows one to calculate the range of possible periods (time between hand throws) for a given type of uniform juggle and a given time of flight,” he wrote. “A juggler can change this period, while keeping the height of his throws fixed, by increasing dwell time (to increase the period) or reducing dwell time to reduce the period. The total mathematical range available for a given flight time can be obtained by setting D = 0 for minimum range and V = 0 for maximum range in Theorem 1. The ratio of these two extremes is independent of the flight time and dependent only on the number of balls and hands.”
To measure dwell times, Shannon actually created a “jugglometer” in which a juggler wore copper mesh over his fingers and juggled foil-covered lacrosse balls; catching the ball closed a connection between the fingers and started a clock. “Preliminary results from testing a few jugglers indicate that, with ball juggling, vacant time is normally less than dwell time, V ranging in our measurements from fifty to seventy per cent of D.”
Shannon noted that juggling gets dramatically harder as the number of balls increases. He worked out a foolproof solution, at least in theory. A light ray that starts at one focus of an ellipse will be reflected to the other focus. If the ellipse is rotated around its major axis, it will create an egglike shell with two foci. Now if a juggler stands with a hand at each focus, then a ball thrown from either hand, in any direction, will bounce off the shell and arrive at the other hand!
(“Scientific Aspects of Juggling,” in Claude Elwood Shannon: Collected Papers, 1993.)
In 1980 Philip K. Dick was asked to forecast some significant events in the coming years. Among his predictions:
1983: The Soviet Union will develop an operational particle-beam accelerator, making missile attack against that country impossible. At the same time the U.S.S.R. will deploy this weapon as a satellite killer. The U.S. will turn, then, to nerve gas.
1989: The U.S. and the Soviet Union will agree to set up one vast metacomputer as a central source for information available to the entire world; this will be essential due to the huge amount of information coming into existence.
1993: An artificial life form will be created in a lab, probably in the U.S.S.R., thus reducing our interest in locating life forms on other planets.
1997: The first closed-dome colonies will be successfully established on Luna and on Mars. Through DNA modification, quasi-mutant humans will be created who can survive under non-Terran conditions, i.e., alien environments.
1998: The Soviet Union will test a propulsion drive that moves a starship at the velocity of light; a pilot ship will set out for Proxima Centaurus, soon to be followed by an American ship.
2000: An alien virus, brought back by an interplanetary ship, will decimate the population of Earth, but leave the colonies on Luna and Mars intact.
2010: Using tachyons (particles that move backward in time) as a carrier, the Soviet Union will attempt to alter the past with scientific information.
Also: “Computer use by ordinary citizens (already available in 1980) will transform the public from passive viewers of TV into mentally alert, highly trained, information-processing experts.”
(From David Wallechinsky, Amy Wallace, and Irving Wallace, The Book of Predictions, 1980.)
The editors of the Journal of Organic Chemistry received a novel submission in 1970 — Brown University chemists J.F. Bunnett and Francis Kearsley wrote their paper “Comparative Mobility of Halogens in Reactions of Dihalobenzenes With Potassium Amide in Ammonia” in blank verse:
Reactions of potassium amide
With halobenzenes in ammonia
Via benzyne intermediates occur.
Bergstrom and associates did report,
Based on two-component competition runs,
Bromobenzene the fastest to react,
By iodobenzene closely followed,
The chloro compound lagging far behind,
And flurobenzene to be quite inert
At reflux (-33°).
This goes on for three pages. The journal published it with a note: “Although we are open to new styles and formats for scientific publication, we must admit to surprise upon receiving this paper. However, we find the paper to be novel in its chemistry, and readable in its verse. Because of the somewhat increased space requirements and possible difficulty to some of our nonpoetically inclined readers, manuscripts in this format face an uncertain future in this office.”
(Thanks, Bob.)
French civil engineer Henri Genaille introduced these “rulers” in 1891 as a way to perform simple multiplication problems directly, without mental calculation.
A set consists of 10 numbered rulers and an “index.” To multiply 52749 by 4, arrange rulers 5, 2, 7, 4, and 9 side by side next to the index ruler. We’re multiplying by 4, so go to the 4th row and start at the top of the rightmost column:
Now just follow the gray triangles from right to left:
The answer is 210996. “[Édouard] Lucas gave these rulers enough publicity that they became quite popular for a number of years,” writes Michael R. Williams in William Aspray’s Computing Before Computers. “Unfortunately he never lived to see their popularity grow, for he died, aged 49, shortly after Genaille’s demonstration.”
Ook! is a programming language designed to be understood by orangutans. According to the design specification, the language has only three syntax elements (“Ook.” “Ook?” “Ook!”), and it “has no need of comments. The code itself serves perfectly well to describe in detail what it does and how it does it. Provided you are an orang-utan.”
This example prints the phrase “Hello world”:
Ook. Ook? Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook! Ook? Ook? Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook? Ook! Ook! Ook? Ook! Ook? Ook. Ook! Ook. Ook. Ook? Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook! Ook? Ook? Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook? Ook! Ook! Ook? Ook! Ook? Ook. Ook. Ook. Ook! Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook! Ook. Ook! Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook! Ook. Ook. Ook? Ook. Ook? Ook. Ook? Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook! Ook? Ook? Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook? Ook! Ook! Ook? Ook! Ook? Ook. Ook! Ook. Ook. Ook? Ook. Ook? Ook. Ook? Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook! Ook? Ook? Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook? Ook! Ook! Ook? Ook! Ook? Ook. Ook! Ook! Ook! Ook! Ook! Ook! Ook! Ook. Ook? Ook. Ook? Ook. Ook? Ook. Ook? Ook. Ook! Ook. Ook. Ook. Ook. Ook. Ook. Ook. Ook! Ook. Ook! Ook! Ook! Ook! Ook! Ook! Ook! Ook! Ook! Ook! Ook! Ook! Ook! Ook. Ook! Ook! Ook! Ook! Ook! Ook! Ook! Ook! Ook! Ook! Ook! Ook! Ook! Ook! Ook! Ook! Ook! Ook. Ook. Ook? Ook. Ook? Ook. Ook. Ook! Ook.
“Um, that’s it. That’s the whole language. What do you expect for something usable by orang-utans?”
See Stage Business and Output.
Tangrams can demonstrate the Pythagorean theorem. The yellow figure in the diagram above is a right triangle; the seven pieces that make up the square on the hypotenuse can be rearranged to form squares on the other two sides.
The third-century mathematician Liu Hui used to explain the theorem by dissecting and rearranging squares. Proper tangrams did not appear until centuries later, but modern Chinese mathematician Liu Dun writes, “We can hypothesize that the inventor of the Tangram, if not a mathematician, was at least inspired or enlightened by” this practice.
(From Jerry Slocum, The Tangram Book, 2003.)
Smallpox ravaged the New World for centuries after the Spanish conquest. In 1797 Edward Jenner showed that exposure to the cowpox virus could protect one against the disease, but the problem remained how to transport cowpox across the sea. In 1802 Charles IV of Spain announced a bold plan — 22 orphaned children would be sent by ship; after the first child was inoculated, his skin would exude fluid that could be passed to the next child. By passing the live virus from arm to arm, the children formed a transmission chain that could transport the vaccine in an era before refrigeration and other modern technology was available.
It worked. Over the next 10 years Spain spread the vaccine throughout the New World and to the Philippines, Macao, and China. Oklahoma State University historian Michael M. Smith writes, “These twenty-two innocents formed the most vital element of the most ambitious medical enterprise any government had ever undertaken.” Jenner himself wrote, “I don’t imagine the annals of history furnish an example of philanthropy so noble, so extensive as this.”
A charming little scene from mathematical history — in 1615 Gresham College geometry professor Henry Briggs rode the 300 miles from London to Edinburgh to meet John Napier, the discoverer of logarithms. A contemporary witnessed their meeting:
He brings Mr. Briggs up into My Lord’s chamber, where almost one quarter of an hour was spent, each beholding the other with admiration, before one word was spoke: at last Mr. Briggs began. ‘My Lord, I have undertaken this long journey purposely to see your person, and to know by what engine of wit or ingenuity you came first to think of this most excellent help unto Astronomy, viz. the Logarithms: but my Lord, being by you found out, I wonder nobody else found it before, when now being known it appears so easy.’
Their friendship was fast but short-lived: The first tables were published in 1614, and Napier died in 1617, perhaps due to overwork. In his last writings he notes that “owing to our bodily weakness we leave the actual computation of the new canon to others skilled in this kind of work, more particularly to that very learned scholar, my dear friend, Henry Briggs, public Professor of Geometry in London.”
A “self-interlocking” geomagic square by Lee Sallows. The 16 lettered pieces pave a single large square, and smaller squares can be produced by various groups of four pieces — those drawn from each row, column, and long diagonal, and 10 other symmetrically chosen quartets.
