History
Ultrasonic cleaners began being used in industry in about 1950, and came into use as relatively inexpensive home appliances in about 1970.
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Famous quotes containing the word history:
“The true theater of history is therefore the temperate zone.”
—Georg Wilhelm Friedrich Hegel (1770–1831)
“All things are moral. That soul, which within us is a sentiment, outside of us is a law. We feel its inspiration; out there in history we can see its fatal strength.”
—Ralph Waldo Emerson (1803–1882)
“My good friends, this is the second time in our history that there has come back from Germany to Downing Street peace with honour. I believe it is peace for our time. We thank you from the bottom of our hearts. And now I recommend you to go home and sleep quietly in your beds.”
—Neville Chamberlain (1869–1940)