Vaccine, Battery, Arc Light, Atoms

Smallpox is caused by a virus. A vaccine is a cure for or treatment of a disease. The vaccine was introduced in America in 1780. Massachusetts required mandatory vaccination in 1809.

Volta was born in Italy in 1745. Batteries have (+) and (-) terminals. Volta submitted a paper to the Royal Society. Voltage is named after Volta.

Arc light is extremely bright. The light is bright enough to light up large buildings and streets. Generators by 1815 were built to power the arc light. It did not take off quickly.

John Dalton was born in England in 1766. Dalton published his theory in a book. Dalton's Atomic Theory proposed that "all matter was composed of atoms: indivisible, indestructible building blocks." Dalton became a Professor and private tutor.