1870 – He was born on the 27th of July in Amherst, Massachusetts. He was the American pioneer of radiochemistry.
1897-1900 – He graduated from Yale University, and became a teacher.
1907 – He measured the age of rocks by the decay of uranium to lead.
– He got results of ages of 400 to 2200 million years, the first success of radiometric dating.
1927 – Bertram Borden Boltwood died at Hancock Point, Maine.