Another influential older cylindrical color model is the early-20th-century Munsell color model. Albert Munsell began with a spherical model in his 1905 book "A Color Notation", but he wished to separate color-making attributes into separate dimensions, which he called "hue", "value", and "chroma. A"fter taking careful measurements of human perception, he realized that no symmetrical shape would fit. So he reorganized his system into a blob.