Downtube shift levers were very common on drop bar bikes for a long time. Pictured are SunTour Power Shifters, my favorites, with a racheting mechanism.
Similar stem-mounted shifters were also common.
All shift levers that I am aware of, with a few rare exceptions, are finger-operated.
Downtube shifters are occasionally seen on bikes in the Land of the Hoosiers.
Downtube shifters were common at least through the '80's.