On this day in 1800, the United States Congress held its first session in Washington, D.C.
On this day in 1869, the Suez Canal, linking the Mediterranean Sea with the Red Sea, was inaugurated in Egypt.
On this day in 1947, American scientists John Bardeen and Walter Houser Brattain observed the basic principles of the transistor, a key element for the electronics revolution of the 20th century.