It was in October of 1964 when I first used a TEM, it was at the Siemens training school run by their agent Aeon Laboratories. A service engineer (we didn't call them technicians in those days), Robin Willis ran the course, five days for just alignment and cleaning! Robin, by the way, moved to University College London, Anatomy department and became the first person to publish on the tilting of biological samples. He actually invented tomography without knowing it! He used a fish tank within which he hung the negatives of his +60 to -60 tilt series. This procedure created a three dimensional image of the thin section, again I would guess, for the first time.