Castoreum a tincture in some perfumes and as a food additive. The government of Ontario pays trappers to harvest beaver castor sacs. The sacs brought between 2.62 - 5.10 Canadian dollars per ounce when auctioned at the May–June 2016 North American Fur Auction. At least 24 compounds are known constituents of beaver castoreum. Some of these have pheromonal activity. These are the phenols 4-ethylphenol and 1,2-dihydroxybenzene (catechol) and the ketones acetophenone and 3-hydroxyacetophenone. Five additional compounds noted are 4-methyl-1,2-dihydroxybenzene (4-methylcatechol), 4-methoxyacetophenone, 5-methoxysalicylic acid, salicylaldehyde, and 3-hydroxybenzoic acid. Other neutral compounds are oxygen-containing monoterpenes such as 6-methyl-l-heptanol, 4,6-dimethyl-l-heptanol, isopinocamphone, pinocamphone, two linalool
Castor and Pollux a blow from his spear—but not before Castor called out to warn Pollux. In the ensuing brawl, Pollux killed Lynceus. As Idas was about to kill Pollux, Zeus, who had been watching from Mt. Olympus, hurled a thunderbolt, killing Idas and saving his son. Returning to the dying Castor, Pollux was given the choice by Zeus of spending all his time on Mount Olympus or giving half his immortality to his mortal brother. He opted for the latter, enabling the twins to alternate between Olympus and Hades. The brothers became the two brightest stars in the constellation Gemini ("the twins"):