- 1930Research Chemist
- 1941[position unknown]
- 1942[position unknown]
- 1943[position unknown]
- 1944[position unknown]
- 1945[position unknown]
- 1946[position unknown]
- 1947[position unknown]
- 1948[position unknown]
- 1949[position unknown]
- 1950[position unknown]
- 1951[position unknown]
- 1952[position unknown]
- 1953[position unknown]
- 1954[position unknown]
- 1955[position unknown]
- 1956[position unknown]
- 1957[position unknown]
- 1958[position unknown]