Silvanus P. Thompson was born
Silvanus Phillips Thompson was an English professor of physics at the City and Guilds Technical College in Finsbury, England. He was elected to the Royal Society in 1891 and was known for his work as an electrical engineer and as an author. Thompson's most enduring publication is his 1910 text Calculus Made Easy, which teaches the fundamentals of infinitesimal calculus, and is still in print.
1718 Tongwei-Gansu earthquake
The 1718 Tongwei-Gansu earthquake occurred on June 19, 1718, in Tongwei County, Gansu Province, Qing dynasty, present-day China. The estimated surface wave magnitude (Ms) 7.5 earthquake was assigned a maximum Modified Mercalli intensity of X (Extreme), causing tremendous damage and killing 73,000 people.