**I never came across one of Laplace's "Thus it plainly appears"**

**without feeling sure that I have hours of hard work before me to fill up the chasm**

**and find out and show how it plainly appears.**

(LaPlace's classic, "Mecanique Celeste", is a very difficult book, and Biot, who helped him prepare it for printing said that Laplace himself would frequently get lost in following his own line of reasoning and insert, "il est aise a voir".

Bowditch translated the work and Legendre wrote of the translation, "Your work is not merely a translation with a commentary; I regard it as a new edition, augmented and improved, and such a one as might have come from the hands of the author himself, ... if he had been solicitously studious of being clear." )

The 189th day of the year; the product of the primes in a prime quadruplet always end in 189, except for the very first quadruplet 3x5x7x11.(

*A prime quadruplet (sometimes called prime quadruple) is a set of four primes of the form {p, p+2, p+6, p+8} you can see some of the smaller ones listed here*

There are 14 prime years in the 21st Century (2017 will be the third), but the 189th century would be the first to contain as few as five prime years (18803, 18839, 18859, 18869 and 18899).

Narayana, an Indian mathematician in the 14th century, came up with an interesting Fibonacci-like series: A cow produces one calf every year. Beginning in its fourth year, each calf produces one calf at the beginning of each year. How many cows and calves are there altogether after n years? For the 15th year, the total is 189. (How many mature and immature?)

2357 is a prime number. 23357 is also prime. 233357 is also prime but 2333357 is not, and then 23333357 is; and yes, this is somehow related to the number 189. I came across a sequence on OEIS which gave "Numbers k such that (7*10^k + 71)/3 is prime." Like you may have, I wondered, "Why would someone search for primes of so unusual a sequence?" Well, if you take those prime numbers, and subtract 2 from them, you get the number of threes that when placed between the digit 2 and the digits 57, will produce a prime. So I can inform you today that not only is (7*10

^{189}+71 )/3 a prime number, but that prime number is a 2 followed by 187 threes followed by 57.

*And you thought 189 was just some hum-drum number!!!!!*

**1672**Newton's first publication is in a letter to the Philosophical Transactions: “A Serie’s of Quere’s Propounded by Mr. Isaac Newton, to be Determin’d by Experiments, Positively and Directly Concluding His New Theory of Light and Colours; and Here Recommended to the Industry of the Lovers of Experimental Philosophy, as they Were Generously Imparted to the Publisher in a Letter of the Said Mr. Newtons of July 8.1672” (Thanks to Thony Christie) *Philosophical Transactions

**1680**Hooke demonstrates sound vibration. This was done by putting flour on a glass plate, and bowing on the edge of glass. Hooke had observed that the motion of the glass was vibrate perpendicular to the surface of the glass, and that the circular figure of the flour changed into an oval one way, and the reciprocation of it changed it into an oval the other way. This phenomenon was rediscovered by Chladni in the eighteenth century, and given his name "Chladni figures". *Daniel P McVeigh, "An Early History of the Telephone 1664-1865"

**1706**de Moivre wrote to Johann Bernoulli on 8 July 1706 telling him about Machin's series for π he suggested that Johann Bernoulli might tell Jakob Hermann about Machin's unproved result. He did so and Hermann quickly discovered a proof that Machin's series converges to π. He produced techniques that show other similar series also converge rapidly to π and he wrote on 21 August 1706 to Leibniz giving details. Two years later, on 6 July 1708, de Moivre wrote again to Johann Bernoulli about Machin's series, on this occasion giving two different proofs that it converged to π.

In 1706 William Jones published a work Synopsis palmariorum matheseos or, A New Introduction to the Mathematics, Containing the Principles of Arithmetic and Geometry Demonstrated in a Short and Easie Method ... Designed for ... Beginners. (This is the book in which Jones first uses Pi in the mathematical sens it is now used) This contains on page 243 the following passage:-

There are various other ways of finding the lengths or areas of particular curve lines, or planes, which may very much facilitate the practice; as for instance, in the circle, the diameter is to the circumference as 1 to (16/5- 4/239) - 1/3(16/53- 4/2393) &c. = 3.14159 &c. = π. This series (among others for the same purpose, and drawn from the same principle) I received from the excellent analyst, and my much esteemed friend Mr John Machin; and by means thereof, van Ceulen's number, or that in Art. 64.38 may be examined with all desirable ease and dispatch.

Jones also reports that this formula allows π be calculated:-

... to above 100 places; as computed by the accurate and ready pen of the truly ingenious Mr John Machin. No indication is given in Jones's work, however, as to how Machin discovered his series expansion for π.

**1831**Quetelet officially uses the term, "l'homme moyen" in an article about the different ages at which men commit crimes. *Statistics on the Table: The History of Statistical Concepts and Methods By Stephen M. Stigler

**1835**Liberty bell cracked. *VFR

*Or maybe not*In the 1830s, the bell was adopted as a symbol by abolitionist societies, who dubbed it the "Liberty Bell". It acquired its distinctive large crack sometime in the early 19th century—a widespread story claims it cracked while ringing after the death of Chief Justice John Marshall in 1835.*Wik

**1842**Francis Baily (1774-1844) UK, at an eclipse in Italy, focuses attention on the corona and prominences and identifies them as part of the Sun's atmosphere. *NSEC

**1842**Dominique Francois Jean Arago (1786-1853), French astronomer. Studied solar eclipse of July 08, 1842 and concluded the sun exist of gas.*NSEC

**1881**, a patron came into Edward Berner's drug store in Two Rivers, Wisconsin, and sat down at the soda-fountain counter. Since it was the Sabbath, the customer couldn't have the desirable, but scandalous, flavored soda water. Berner compromised by putting ice cream in a dish and poured over it the chocolate syrup that was previously only served as flavoring in ice-cream sodas. That was an ice cream Sunday! The name became "sundae", after the day on which Berner served it. TIS

**1933**Jansky announced detection of radio radiation from galactic center.*VFR Before Jansky observed the Milky Way in the 1930s, physicists speculated that radio waves could be observed from astronomical sources. In the 1860s, James Clerk Maxwell's equations had shown that electromagnetic radiation is associated with electricity and magnetism, and could exist at any wavelength. Several attempts were made to detect radio emission from the Sun by experimenters such as Nikola Tesla and Oliver Lodge, but those attempts were unable to detect any emission due to technical limitations of their instruments.

Karl Jansky made the discovery of the first astronomical radio source serendipitously in the early 1930s. As an engineer with Bell Telephone Laboratories, he was investigating static that interfered with short wave transatlantic voice transmissions. Using a large directional antenna, Jansky noticed that his analog pen-and-paper recording system kept recording a repeating signal of unknown origin. Since the signal peaked about every 24 hours. *Wik

**2002**Well into his mid-nineties, Donald Coxeter gives the keynote address at the Janos Bolyai Conference on Hyperbolic Geometry with a new paper on the Descartes circle theorem as extended by Phillip Beecroft. His Opening remarks:

The Absolute property of four mutally tangent circles that I am describing seems to have been discovered by Mr. Phillip Beecroft, of Hyde Academy, Cheshire, England, and published in The Lady and Gentleman's Dairy... In Beecroft's own words, "If any four circles be described to touch each other mutually, another set of four circles of mutual contact may be described whose points of contach shall coincide with those of the first four." He then proceeded to give a new and elegant proof of the 1842 theorem, which extended the four circle theorem of Descartes to be, in essence, an eight circle theorem.*Siobhan Roberts, King of Infinite Space

**BIRTHS**

**1760 Christian Kramp**(July 8, 1760 – May 13, 1826) was a French mathematician, who worked primarily with factorials.

As Bessel, Legendre and Gauss did, Kramp worked on the generalised factorial function which applied to non-integers. His work on factorials is independent of that of James Stirling and Vandermonde. He was the first to use the notation n! (Elements d'arithmétique universelle, 1808). In fact, the more general concept of factorial was found at the same time by Arbogast.*TIS For more on the symbols and history of the factorial see here.

**1777 Daniel Friedrich Hecht**(8 July 1777 in Sosa – 13 March 1833 in Saxony) was a German mathematician. He was a mine manager, then a teacher and finally a professor of mathematics. He is most notable for writing high school textbooks on maths and geometry. *Wik

**1838 Count Ferdinand von Zeppelin**Germany aviation pioneer who built the first rigid dirigible airships, named Zeppelins. He patented his idea on 31 Aug 1895 and formed a company to build airships in 1898. Many thought his invention incredible, and called him "Foolish Count". His first airship took off in 2 Jul 1900 at Lake Constance, where it had been assembled in a floating assembly shed. He continued to improve the design and built a fleet of airships for commercial passenger service. During WW I, Zeppelins were used to bomb Britain beginning 19 Jan 1915 with attacks on Great Yarmouth and King's Lynn. After the war, passenger service included transatlantic flights. Zeppelin use ended after the 6 May 1937 Hindenburg fire disaster at Lakehurst, N.J., U.S.A.*TIS

**1895 Igor Yevgenyevich Tamm**(8 July 1895 – 12 April 1971) Soviet physicist who shared the 1958 Nobel Prize for Physics with Pavel A. Cherenkov and Ilya M. Frank for his efforts in explaining Cherenkov radiation. Tamm was an outstanding theoretical physicist, after early researches in crystallo-optics, he evolved a method for interpreting the interaction of nuclear particles. Together with I. M. Frank, he developed the theoretical interpretation of the radiation of electrons moving through matter faster than the speed of light (the Cerenkov effect), and the theory of showers in cosmic rays. He has also contributed towards methods for the control of thermonuclear reactions. *TIS

one of my favorite math stories is from George Gamow's autobiography and is about Tamm.

"Here is a story told to me by one of my friends who was at that time

a young professor of physics in Odessa. His name was Igor Tamm (Nobel

Prize laureate in Physics, 1958). Once when he arrived in a neighboring

village, at that period when Odessa was occupied by the Reds, and was

negotiating with a villager as to how many chickens he could get for

half a dozen silver spoons, the village was captured by one of the

Makhno bands, who were roaming the country, harassing the Reds. Seeing

his city clothes (or what was left of them), the capturers [sic]

brought him to the Ataman, a bearded fellow in a tall black fur

hat with machine-gun cartridge ribbons crossed on his broad chest and

a couple of hand grenades hanging on the belt.

'You son-of-a-bitch, you Communist agitator, undermining our Mother

Ukraine! The punishment is death.'

'But no,' answered Tamm, 'I am a professor at the University of Odessa

and have come here only to get some food.'

'Rubbish!' retorted the leader. 'What kind of professor are you ?'

'I teach mathematics.'

'Mathematics?' said the Ataman. 'All right! Then give me an estimate of

the error one makes by cutting off Maclaurin's series at the nth term.

Do this, and you will go free. Fail, and you will be shot!'

Tamm could not believe his ears, since this problem belongs to a rather

special branch of higher mathematics. With a shaking hand, and under

the muzzle of the gun, he managed to work out the solution and handed

it to the Ataman.

'Correct!' said the Ataman. 'Now I see that you really are a professor.

Go home!'

Who was this man? No one will ever know. If he was not killed later, he

may well be lecturing now on higher mathematics in some Ukrainian

university."

I tell this story every other year or so to my physics students when

they cannot be bothered to remember the form of the remainder in Taylor

expansions....

**1904 Henri (-Paul) Cartan**, (July 8, 1904 – August 13, 2008) mathematician born in Nancy, France. His father, Elie Cartan, was also a mathematician. Henri made fundamental advances in the theory of analytic functions, worked on the theory of sheaves, homological theory, algebraic topology and potential theory. Along with others, such as Weil and Dieudonné, Henri Cartan wrote under the name Bourbaki. Bourbaki's Eléments de mathématique contains more than 30 volumes and aims to present mathematics so as to illustrate the axiomatic structure of modern mathematics. *TIS

**1915 Kenneth O. May**(July 8, 1915, Portland, Or. – December 1,1977) was an American mathematician and historian of mathematics, who developed May's theorem. The Kenneth O. May Prize is awarded for outstanding contributions to the history of mathematics. Ken May established Historia Mathematica, and preserved it by separating it from its creator, "The distinguished predecessors of HM were associated with their founders and died with them. If HM is to avoid this fate, we must prepare and carry through a prompt transfer of editorial responsibility to younger hands." His list of publications numbers above 300. *Henry S. Tropp, E'loge, Isis 70, Sept 1979, Pgs 419-422

**DEATHS**

**1390 Albert of Saxony**died. He wrote an excellent logic text and published two works on squaring the circle. *VFR ert was born at Rickensdorf near Helmstedt, the son of a farmer in a small village; but because of his talent, he was sent to study at the University of Prague and the University of Paris.

At Paris, he became a master of arts (a professor), and held this post from 1351 until 1362. In 1353, he was rector of the University of Paris. After 1362, Albert went to the court of Pope Urban V in Avignon as an envoy of Rudolf IV, Duke of Austria, in order to negotiate the founding of the University of Vienna. The negotiations were successful, and Albert became the first rector of this University in 1365.

In 1366, Albert was elected bishop of Halberstadt (counted as Albert III), Halberstadt being the diocese in which he was born. As Bishop of Halberstadt, he allied himself with Magnus with the Necklace, Duke of Brunswick-Lüneburg, against Gebhard of Berg, Bishop of Hildesheim, and was taken prisoner by Gebhard in the battle of Dinckler in 1367.

He died at Halberstadt in 1390.*Wik

**1695 Christiaan Huygens**(14 April 1629 – 8 July 1695) Dutch mathematician, astronomer, and physicist, who founded the wave theory of light, discovered the true shape of the rings of Saturn, and contributed to the science of dynamics - the study of the action of forces on bodies. Using a lens he ground for himself, on 25 Mar 1655, he discovered the first moon of Saturn, later named Titan. In 1656, he patented the first pendulum clock, which he developed to enable exact time measurement while observing the heavens. Huygens studied the relation of the length of a pendulum to its period of oscillation (1673) and stated theories on centrifugal force in circular motion which influenced Sir Isaac Newton in formulating his Law of Gravity. Huygens also studied and drew the first maps of Mars. On 14 Jan 2005, a NASA space probe, named after Huygens, landed on Titan. *TIS

**1902 John Daniel Runkle**(October 11, 1822 – July 8, 1902) was a U.S. educator and mathematician. B.S. in mathematics, 1851, Harvard College, second president of the Massachusetts Institute of Technology, was associated with the Nautical Almanac computation project from 1849 to 1884. In 1858 he founded the journal Mathematical Monthly and edited it for three years, when publication ceased. In 1860 he was a member of the committee that prepared the “Objects and Plan of an Institute of Technology” which led to the establishment of MIT. In 1862 he became MIT’s first secretary, and in 1865 he joined the new faculty as professor of mathematics, where he remained until 1902. He served as president pro-tem, 1868-1870, and was MIT’s second president, 1870-1878. He was married to Catherine Robbins Bird Runkle. *MIT History

**1971 Kurt Werner Friedrich Reidemeister**(October 13, 1893 – July 8, 1971) was a mathematician born in Braunschweig (Brunswick), Germany.

He received his doctorate in 1921 with a thesis in algebraic number theory at the University of Hamburg under the supervision of Erich Hecke. In 1923 he was appointed assistant professor at the University of Vienna. While there he became familiar with the work of Hans Hahn and Wilhelm Wirtinger. In 1925 he became full professor at University of Königsberg, where he stayed until 1933, when he was forced to leave because of his opposition of the Nazis.

Reidemeister's interests were mainly in combinatorial group theory, combinatorial topology, geometric group theory, and the foundations of geometry. His books include Knoten und Gruppen (1926), Einführung in die kombinatorische Topologie (1932), and Knotentheorie (1932). He was the brother of Marie Neurath.*Wik

**1979 Shin'ichiro Tomonaga**(March 31, 1906 – July 8, 1979) Japanese physicist who shared the Nobel Prize for Physics in 1965 (with Richard P. Feynman and Julian S. Schwinger of the U.S.) for independently developing basic principles of quantum electrodynamics. He was one of the first to apply quantum theory to subatomic particles with very high energies. Tomonaga began with an analysis of intermediate coupling - the idea that interactions between two particles take place through the exchange of a third (virtual particle), like one ship affecting another by firing a cannonball. He used this concept to develop a quantum field theory (1941-43) that was consistent with the theory of special relativity. WW II delayed news of his work. Meanwhile, Feynman and Schwinger published their own independent solutions.

2008 Sixto Ríos García (January 4, 1913; Pelahustán, Toledo - July 8, 2008; Madrid,) was a Spanish mathematician, known as the father of Spanish statistics.

He has held the positions of Director of the School of Statistics at the University of Madrid, Director of the Institute for Operations Research and Statistics CSIC, Director, Department of Statistics, Faculty of Mathematical Sciences at the Complutense University and President of the Spanish Society Operational Research, Statistics and Information. It was academic correspondent of the National Academy of Sciences of Buenos Aires, and organizer and founder, commissioned by Unesco, School of Statistics, University of Caracas. He was a member of the drafting committee of Statistical Abstracts and fellow of the International Statistical Institute and the Institute of Mathematical Statistics. Wik-ES

**2010 David Harold Blackwell**(April 24, 1919 – July 8, 2010) was Professor Emeritus of Statistics at the University of California, Berkeley, and is one of the eponyms of the Rao–Blackwell theorem. Born in Centralia, Illinois, he was the first African American inducted into the National Academy of Sciences, and the first black tenured faculty member at UC Berkeley.*Wik

Credits :

*CHM=Computer History Museum

*FFF=Kane, Famous First Facts

*NSEC= NASA Solar Eclipse Calendar

*RMAT= The Renaissance Mathematicus, Thony Christie

*SAU=St Andrews Univ. Math History

*TIA = Today in Astronomy

*TIS= Today in Science History

*VFR = V Frederick Rickey, USMA

*Wik = Wikipedia

*WM = Women of Mathematics, Grinstein & Campbell