Wildlife of China "ciwei" or the "thorned creature". Porcupines are rodents and hedgehogs belong to a separate order. Three species of Old World porcupine are found in China: the Asiatic brush-tailed porcupine, Indian crested porcupine, and Malayan porcupine. Many parts of the porcupine including the brain, organs, fat, quills and even the feces can be used to make traditional Chinese medicine. Porcupines are raised on farms. In the early 20th century, the Eurasian beaver was hunted to near extinction for its fur and castoreum, a scent gland secretion used to make perfume and medicine. Though the global population has rebounded, the animal remains
Castor oil and others. The production of lithium grease consumes a significant amount of castor oil. Hydrogenation and saponification of castor oil yields 12-hydroxystearic acid which is then reacted with lithium hydroxide or lithium carbonate to give high performance lubricant grease. Since it has a relatively high dielectric constant (4.7), highly refined and dried castor oil is sometimes used as a dielectric fluid within high performance high voltage capacitors. Vegetable oils like castor oil are typically unattractive alternatives to petroleum-derived lubricants because of their poor oxidative stability. Castor oil has better low-temperature viscosity properties and high-temperature lubrication than most vegetable oils, making