He retired from this post in 1964 .
He eventually became a chemist ( 1937 ) , senior chemist ( 1941 ) , and finally Chief of the Minerals Thermodynamics Branch ( 1959 ) .
senior chemist retired from this post in 1964 .
He eventually became a chemist ( 1937 ) , senior chemist ( 1941 ) , and finally Chief of the Minerals Thermodynamics Branch ( 1959 ) .