Perfume is a mixture of alcohol and fragrant essential oils. Animal substances—such as musk, ambergris, and civet—were first added as fixatives in the Middle Ages. Since the early 19th century, chemists have produced thousands of synthetic essential oils, some imitating natural products and others yielding new scents. Most perfumes today are blends of natural and synthetic scents and of fixatives that add pungency. Fine perfumes may blend more than 100 ingredients. What is a fragrance wheel? Discuss