In the late 1950s there were basically three different approaches reported for bacterial synchronization: single or multiple temperature shifts, single or multiple nutritional deprivations, and size selection by filtration or centrifugation (Helmstetter, 1969). I tried all of them over and over with limited success. These were not trivial efforts because cell concentrations were all determined using agar plates, requiring pouring, plat- ing, counting, and cleaning hundreds of glass Petri dishes every week. That was the case until 1 day a guy named Joe Coulter, who along with his brother had started a small electronics firm in Chicago, walked into the laboratory carrying a machine he claimed could accurately count thousands of bacteria in seconds. After he had considerable difficulty getting mercury to fill the new manometer during set-up of the instrument (not uncommon for an inexperienced user but a bit surprising in retrospect for some- one named Coulter), it worked! This was, of course, the original Coulter Counter model A. Now I was able to not only get rapid, accurate cell concentrations, but I was also able to simultaneously see the “sizes” of the cells on the integrated oscilloscope. With the model A amplifiers and a 30-µm aperture tube, the size distribu- tions of exponential-phase, newborn and synchronously growing cells were readily distinguishable. This instrument proved to be invaluable for my work, and the work of many others who dared try to employ synchronously dividing cells