In celebration of the centenary of August Müller's pioneering work on contact lenses, we present, for the first time, a full translation into English of Part III of his inaugural dissertation. Müller describes his attempts to correct his own -14.00 diopters of myopia with "cornea-lenses," which were essentially glass scleral lenses. His inability to tolerate lens wear for more than half an hour was probably due to a) limbal pressure as a result of the primary optic diameter being too small, and b) the use of water to occupy the space between the lens and cornea, which would have induced severe corneal edema. Many of the observations and recommendations embodied in Müller's thesis, such as the importance of a good fit, adequate tear flow and rounded edges, are still relevant to contact lens practice today.