The human mind has never invented

a labor-saving machine equal to algebra.

~Author Unknown

The 130th day of the year; 130 is the sum of the factorials of the first five terms of the Fibonacci sequence. 130 is also the **only**number equal to the sum of the squares of its first 4 divisors: 130 = 1^2 + 2^2 + 5^2 + 10^2.*Prime Curios

**1694**Johann Bernoulli, in a letter to Leibniz, introduced the term and the explicit process of “seperatio indeterminatarum” or separation of variables for solving diﬀerential equations. He published it in Acta eruditorum in November, 1694. [Ince, 531] *VFR In 1691 the inverse problem of tangents led Leibniz to the implicit discovery of the method of separation of variables.

1831 Galois party toast will lead to his arrest. Derbyshire describes the events in "Unknown Quantity, a real and imaginary history of Algebra."

**1848**“Proﬁciency in Algebra, the elements of geometry, trigonometry, and surveying, will give you the art of developing truth by the skilful use of the reasoning powers, and, besides, store your mind with a species of knowledge of daily practical utility to a lawyer. ... It is the helm of the mind, stering it over the shortest route from the point of departure to the destination—from cause to eﬀect.” So wrote the American soldier Albert Sindney Johnson (1803–1862) to his son. From William Preston Johnson (the son), The Life of General Albert Sindney Johnson (1878),p. 162, as quoted by Florian Cajori in Mathematics in Liberal Education (1928), p. 103. *VFR

**1854**There is a "letter from Rankine to Thomson of 9 May 1854 in which he suggests more reasonably that the leading term in the departure from the perfect-gas laws is linear in the density, or (1/V). This turned out to be so .." (

*JAMES JOULE, WILLIAM THOMSON AND THE CONCEPT OF A PERFECT GAS by J. S. ROWLINSON*)

**1914**Think of all the work that mothers do in raising their children. Mothers need to be celebrated! President Woodrow Wilson proclaimed May 9, 1914, the first Mother's Day. He asked Americans on that day to give a public "thank you" to their mothers and all mothers.

Anna Jarvis of Philadelphia wanted to remember her own mother along with all mothers. Anna’s mother had been very active in working to improve the health of people in her community. Jarvis’s mother also organized a Mother’s Friendship event in her community to bring confederate and union soldiers together for a peaceful celebration. Many other women such as Julia Ward Howe, Elizabeth Cady Stanton and Elizabeth Smith also fought for peace and encouraged mothers to speak out. Anna Jarvis convinced her mother’s church to celebrate Mother’s Day on the anniversary of her mother’s death, and campaigned for a national day honoring mothers. Because of Jarvis’s hard work, Woodrow Wilson chose that date for the national holiday. (Library of Congress web site) This year it's May 13... Happy Birthday to Mom's everywhere.

**1926**Americans Richard Byrd and Floyd Bennett became the first men to fly over the North Pole. *TIS

**1972**100 high school students took the ﬁrst U.S.A. Mathematical Olympiad. The purpose was to discover secondary school students with superior mathematical talent. One of the ﬁve problems on the exam was: “A random number selector can only select one of the nine integers 1, 2,..., 9, and it makes these selections with equal probability. Determine the probability that after n selections (for n larger than 1), the product of the n numbers selected will be divisible by 10.” For the winners, the other problems, and the solutions, see AMM 80 (1973), pp 276–281. *VFR

**BIRTHS**

**1746 Gaspard Monge,**(9 May 1746 – 28 July 1818) noted geometer, son of a peddler and knife grinder, at Beaune, France. Today there is a statue of him in his home town of Beaune, France. (I stumbled across it while visiting vineyards).*VFR One of the founders of descriptive geometry (the mathematics of projecting solid figures onto a plane, upon which modern engineering drawing is based) and the application of the techniques of analysis to the theory of curvature. The latter ultimately led to the revolutionary work of Georg Riemann on geometry and curvature. He became a close friend of Napoleon and was appointed minister for the navy (1792-93), but was stripped of all honours on the restoration of the Bourbons. He died in poverty. *TIS As an active Jacobin, he was acting head of the government on the day Louis XVI was executed. He was also Minister of the Navy. He was in official disfavor when he died and had been expelled from the Academy in 1816 (along with Lazare Carnot), but his students erected a monument with a bust. MONGE was buried in the cemetery of Père Lachaise (Mausoleum at right below) but in 1989, he was translated to the Panthéon.

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**1785 James Pollard Espy**(9 May 1785, 24 Jan 1860) American meteorologist who was one of the first to collect meteorological observations by telegraph. He gave apparently the first essentially correct explanation of the thermodynamics of cloud formation and growth. Every great atmospheric disturbance begins with a rising mass of heated, thus less dense air. While rising, the air mass dilates and cools. Then, as water vapour precipitates as clouds, latent heat is liberated so the dilation and rising continues until the moisture of the air forming the upward current is practically exhausted. The heavier air flows in beneath, and, finding a diminished pressure above it, rushes upward with constantly increasing violence. Water vapour precipitated during this atmospheric disturbance results in heavy rains.*TIS

**1876 Gilbert Ames Bliss**(9 May 1876, Chicago – 8 May 1951, Harvey, Illinois) did important work in the calculus of variations. Throughout his career at Chicago he stressed the importance of a strong union between teaching and research. *VFR This is another one who died within a week of their birthday (he died on May 8).

**1898 Arend Heyting**(May 9, 1898 – July 9, 1980) is important in the development of intuitionistic logic and algebra.He was a student of Luitzen Egbertus Jan Brouwer at the University of Amsterdam, and did much to put intuitionistic logic on a footing where it could become part of mathematical logic. Heyting gave the first formal development of intuitionistic logic in order to codify Brouwer's way of doing mathematics. The inclusion of Brouwer's name in the Brouwer–Heyting–Kolmogorov interpretation is largely honorific, as Brouwer was opposed in principle to any formalisation of intuitionistic logic (and went as far as calling Heyting's work a "sterile exercise"). *Wik

**DEATHS**

**1931 Albert Abraham Michelson**(December 19, 1852 – May 9, 1931) German-born American physicist who accurately measured the speed of light and received the 1907 Nobel Prize for Physics "for his optical precision instruments and the spectroscopic and metrological investigations" he carried out with them. He designed the highly accurate Michelson interferometer and used it to establish the speed of light as a fundamental constant. With Edward Morley, he also used it in an attempt to measure the velocity of the earth through the ether (1887). The experiment yielded null results that eventually led Einstein to his theory of relativity. He measured the standard meter bar in Paris to be 1,553,163.5 wavelengths of the red cadmium line (1892-3). *TIS There is a marker near the place where the experiment was done. It says, "Near this spot, in July 1887, Dr. Albert A. Michelson of Case and Dr. Edward W. Morley of Western Reserve University conducted the world-famous Michelson-Morley experiment, one of the outstanding scientific achievements of the 19th century and a cornerstone of modern physics. In commemoration, this tablet has been set in stone by both colleges on December 19, 1952, the 100th anniversary of Dr. Michelson's birth."

Credits

*CHM=Computer History Museum

*FFF=Kane, Famous First Facts

*SAU=St Andrews Univ. Math History

*TIS= Today in Science History

*VFR = V Frederick Rickey, USMA

*Wik = Wikipedia

*WM = Women of Mathematics, Grinstein & Campbell