a Scottish physicist, mathematician, astronomer, inventor, writer, historian of science and university principal. Most noted for his contributions to the field of optics, he studied the double refraction by compression and discovered the photoelastic effect, which gave birth to the field of optical mineralogy. For his work, William Whewell dubbed him the "Father of modern experimental optics" and "the Johannes Kepler of Optics." He is well-recognized for being the inventor of the kaleidoscope and an improved version of the stereoscope applied to photography.
