Births on June 21

Siméon Denis Poisson

Born on June 21, 1781

Siméon Denis Poisson, French mathematician and physicist (d. 1840)

Baron Siméon Denis Poisson FRS FRSE (French: [si.me.ɔ̃ də.ni pwa.sɔ̃]; 21 June 1781 – 25 April 1840) was a French mathematician and physicist who worked on statistics, complex analysis, partial differential equations, the calculus of variations, analytical mechanics, electricity and magnetism, thermodynamics, elasticity, and fluid mechanics. Moreover, he predicted the Poisson spot in his attempt to disprove the wave theory of Augustin-Jean Fresnel, which was later confirmed.

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Siméon Denis Poisson

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Events on 1781

5 Jan

Richmond, Virginia
American Revolutionary War: Richmond, Virginia, is burned by British naval forces led by Benedict Arnold.
17 Jan

Battle of Cowpens
American Revolutionary War: Battle of Cowpens: Continental troops under Brigadier General Daniel Morgan defeat British forces under Lieutenant Colonel Banastre Tarleton at the battle in South Carolina.
15 Mar

Battle of Guilford Court House
American Revolutionary War: Battle of Guilford Court House: Near present-day Greensboro, North Carolina, 1,900 British troops under General Charles Cornwallis defeat a mixed American force numbering 4,400 in a Pyrrhic victory.
24 Aug

Lochry's Defeat
American Revolutionary War: A small force of Pennsylvania militia is ambushed and overwhelmed by an American Indian group, which forces George Rogers Clark to abandon his attempt to attack Detroit.
17 Oct

Siege of Yorktown
American Revolutionary War: British General Charles, Earl Cornwallis surrenders at the Siege of Yorktown.

Births on June 21

Siméon Denis Poisson

Born on June 21, 1781

References

Choose Another Date

Events on 1781

Richmond, Virginia

Battle of Cowpens

Battle of Guilford Court House

Lochry's Defeat

Siege of Yorktown