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Synchronisation is an essential component of any high speed photographic experiment to combine the three principal components - subject, camera and lighting. Today there are many available equipments to ensure synchronisation for the current industrial and research problems but when the exception occurs, the skill of the good researcher again becomes necessary. It was not until the manufactured plates and films became available in the 1880's that high speed photography became a real tool and the early users had to solve their own timing problems. In general the early techniques were relatively simple but quite effective. Muybridge in his "Animal Motion Studies" arranged that the subjects operated the cameras by cords to the lens shutters. This was extremely effective. But a few researchers wished to look at very rapid events and needed more automatic methods. For example Mach began on photographing bullets and shells requiring timings in the microsecond range. Because he and his collaborators always took photographs and his reputation was so great, his work was always noted and assumed to be original. Some thirty years earlier, in Berlin, Toepler and Holtz under Professor Riess were working on Electrostatic Generators and Sparks which led Toepler on to his brilliant development of the Schlieren technique. His early application of this technique involved the synchronisation of two spark gaps, one as an illuminant and the other as an event such that shock waves were made visible by his Schieren system. The "pictures" in his published papers look like photo-graphs but in fact were engravings from his own drawings after viewing at least hundreds of images. His circuits and the later Mach circuits must be the earliest of our modern electronic circuits and fully deserving of our recognition.
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