These studies are divided into three parts. I. The mechanism of the Penicillin effect. II. A penicillin test based on manometer readings of oxygen metabolism. III. Production of crude penicillin. The production of penicillin in the United States is so far advanced that many points brought out in these studies may be known in this country.
In the first chapter Hirsch demonstrates that penicillin is not bactericidal or bacteriostatic. Penicillin has no effect on inactive staphylococci in culture; only multiplying staphylococci are influenced. His conclusion is that in the presence of penicillin a degeneration of the culture of staphylococci takes place. Their multiplcation is disturbed not quantitatively but qualitatively. A generation of abnormal sterile cells arises, and these cells die rapidly. The respiratory curve shows in the beginning a normal progression and turns suddenly downward.
In unpurified penicillin-barium compound, a second factor is present which has a typical bacteriostatic effect.