Something ‘Snells’ Fishy
How do we, as humans, see something? Simply put, through light! Without light, nothing that is visible would be visible at all! This is because the things that we see truly are material things, but they are visible because of the light that bounces off of them to hit our eyes. This then makes the image appear in our brains and from there, it’s all up to the doctors. According to Tulane University, “Our eyes interpret these wavelengths as different colors. If only a single wavelength or limited range of wavelengths are present and enter our eyes, they are interpreted as a certain color. If a single wavelength is present we say that we have monochromatic light” (Tulane.edu). Yet, the principle of light is absolutely astounding. It has baffled scientist for hundreds of years because of its almost invisible property. We now know that light is made of photons which when explained by Illinois University is “When light is absorbed or emitted, the energy in the wave comes in lumps. The size of those lumps (or "quanta") of energy depends on the frequency. The higher the frequency the more energy per photon” (Illinois.edu). Yet, the existence of light is far more intricate than only a few lumps of energy. Detailed research on light did not begin until modern thinking was called into question. Yet, even with minute knowledge about photons and waves that was possessed, the thought of light was called into question over 2500 years ago by early philosophers. In about 550 B.C., Greek philosopher Pythagoras suggested that "light consists of rays that acting like feelers, travel in straight lines from the eye to the object, and the sensation of sight is obtained when these rays touch the object" (Mts.net). He believed in the principle of particles that had to make up this seemingly intangible object that permeated their everyday life. This theory last until the birth of Christ and new theories came about as to the properties of light. While many of Pythagorean’s theories were either disproved or revised, they gave magnificent insight as to how to explain light and provided perfect headway for more modern thinkers to build their ideas off of. Now, light has many different properties that operate under certain laws that were suspected by philosophers and proven by scientists over thousands of years. One law in particular focuses on the bending of light through a different medium. It was known that, “When a beam of light passed from air to a denser medium, such as water or glass, and struck the surface of the denser medium at an oblique angle, it was bent toward the vertical” (Asimov). The discovery of this principle of light has been translated into many facets of life. All forms of glasses use the refraction of light to enhance the vision of the user. Magnifying glasses and telescopes use lenses to refract the light to make a distorted, distanced figure something to be observed. A surprising use of refraction is, “in Schlieren Photography, which uses the fact that air at different temperatures bends light by different amounts. Since light coming from a denser medium such as glass or water is bent away from the normal, the depth at which an object inside that medium appears to be less than its real depth” (Thinkquest.org). You can even use the refraction of light to measure the speed of light in a gelatin! While the idea of being able to measure the speed of light in a gelatin without expensive, scientific instruments seems far-fetched and impossible, it has been possible for non-scientists since the 17th century when Denis Papin invented what we know today to be gelatin (Ideafinder.com). Before modern science, the idea of measuring the speed of light would have seemed impossible, especially with a homemade desert such as gelatin. Euclid even claimed, “The speed of light must be very high because you can close your eyes (thus making the things you are looking at disappear!) and then, when you open them again,
