This lecture, at the Wilshire school (circa 1950s), is historic because Hinkel was in the process of developing his “Units of Lye” chart. Importantly, this lecture explains that the “Units of Lye” chart is only a guideline; not any sort of law or set prescription. Hinkel was an X-ray engineer for General Electric at the time he met Henri St. Pierre (San Francisco electrologist). Hinkel was using his understanding of X-ray to develop a method so that we can properly balance the two currents used in electrology. In the early days of the blend, there were no meters on the machines, and so the electrologist balanced the AC (high frequency) and DC (direct current) by observing the effects of the currents on the skin … with consideration of the client’s pain factor. It was only when Hinkel’s employees became masters of the blend, that they were given a DC meter so Hinkel could understand what they were already doing. Simply put, the blend technique came BEFORE the development of the “Units of Lye” guidelines. An expert electrologist must never follow any arbitrary rule … but must be able to evaluate the skin (and how the hair epilates) to perform a perfect treatment. No machine, (even the most sophisticated unit), and no chart of any kind can replace what you see and feel with your own senses. Unfortunately, all modern epilators make it impossible to implement several of the little “tricks” Hinkel is speaking about in this lecture.