"My laboratory was always a bit chaotic, but I knew where everything was."

"I had no idea at the time that I was making a discovery that would change the course of medicine."

"It is not often that one finds a substance that is both highly bactericidal and non-toxic to animal tissues."

"The thought that I might have discovered something which would be of value in treating disease was, of course, uppermost in my mind."

"I am not an orator, but a simple bacteriologist."