1878 – He was born on the 17^th day of November this year in New York City and the son of German immigrants.

1903 – He obtained his doctorate from Columbia University. He also becomes a bacteriologist at Roosevelt Hospital until 1905.

1906 – He developed a medium and a simple method to plate anaerobic organisms.

1907 – He was assistant pathologist at St. Luke’s Hospital for three years.

1908 – He was also an instructor for bacteriology at the Columbia University.

1910 – He became associate professor at Stanford University and became full professor after year.

1911 – A full professor at the Columbia University.

1913 – He became a full professor in Harvard University.

1934 – He did extensive work on typhus and developed a vaccine of killed rickettsias that would protect against typhus.

1940 – He died this year.