Martin scale Martin scale The Martin scale is an older version of color scale commonly used in physical anthropology to establish more or less precisely the eye color of an individual; it was created by the anthropologist Martin in the first half of the 20th century. Later he improved this scale with cooperation of Dr. Schulz – the Martin-Schultz scale. The original Martin scale, summarized below, consists of 16 colors (from light blue to dark brown-black) that correspond to the different eye colors observed in nature due to the amount of melanin in the iris. The numbering is reversed in order to
Forel-Ule scale Vol 5 (2010), ) and can be seen as a simple but adequate scale to classify the color of rivers, lakes, seas and oceans. The Forel-Ule observations belong, besides temperature, salinity and Secchi depth, to the oldest oceanographic parameters dating back to 1890. Forel-Ule scale The Forel-Ule Scale is a method to approximately determine the color of bodies of water, used in limnology and oceanography. By means of mixing different chemical (The standard solutions are made with distilled water, ammonia, copper sulphate, potassium-chromate and cobalt-sulphate) a standard color scale is produced in a series of numerically designated vials (1-21) which