5. Juli

One law of gravity for the Moon, the tides, comets and falling apples. The Royal Society had spent its money on a history of fishes, so Halley paid for the printing himself, and wrote to Newton that day that the book was done.

Three books in Latin that derive the orbits of the planets, the tides and the paths of comets from one law of gravity. Samuel Pepys had licensed it for the Royal Society a year before; Edmond Halley paid for the printing and wrote to Newton on this day that it was out. For a century it was the…

He wrote out his theory in about 230 pages and then locked it away, with a letter asking Emma to have it published if he died, and to set aside £400 for an editor. The same year the anonymous Vestiges of the Natural History of Creation appeared and was savaged, which did nothing to hurry him.

By then a museum piece, the automaton was destroyed in the fire that gutted Philadelphia’s Chinese Museum. 142 years later, in the same city, a computer would beat a world champion for the first time.

At lunch in the Neues Palais, Wilhelm II told the Austrian ambassador that Vienna could count on Germany’s full support whatever it did to Serbia, even if Russia came in. The chancellor, Bethmann Hollweg, confirmed it the next day.

The 1st Machine Gun Regiment and sailors from Kronstadt marched armed on the Tauride Palace demanding “All power to the soviets”, which the Soviet refused. The Bolsheviks hesitated to lead. Loyal troops and the government’s claim that Lenin was a German agent broke the movement. About 400 people…

Coubertin’s last Games as president, in his own city. The first Olympic village housed the athletes, the Olympic motto Citius, Altius, Fortius was used for the first time, and Harold Abrahams and Eric Liddell ran the races later told in Chariots of Fire.

Germany’s last great offensive in the east struck both sides of a bulge around Kursk. The Soviets knew it was coming and had dug belts of defences many kilometres deep. After it failed, the Red Army held the initiative for the rest of the war.

Driven in secret to the state president’s office, in a suit a tailor had measured him for in prison, he found that Botha poured the tea. They talked about Afrikaner history. Mandela asked for the release of the political prisoners; within six weeks Botha was gone, and in October his successor…

Cloned from a mammary-gland cell of a six-year-old Finn Dorset ewe, and so named after Dolly Parton. She was the only lamb from 277 fused eggs. Roslin kept her secret until the Nature paper of 27 February 1997.

The Treatment Action Campaign, founded in Cape Town in 1998, sued the government to offer nevirapine, which cuts transmission at birth, beyond a handful of pilot sites. The court ordered it made available across the public health system.

A 35-minute engine burn on the American Fourth of July, with all its instruments switched off to survive the radiation. It found cyclones clustered at both poles.