<P> Lunsford Richardson developed the formula in 1894 when he created a salve for his children, after traveling to France . </P> <P> Active Ingredients: Label reads: Active Ingredients (Purpose) </P> <Table> <Tr> <Th> Ingredient </Th> <Th>% </Th> <Th> Purpose </Th> </Tr> <Tr> <Td> Camphor (synthetic) </Td> <Td> 4.8% </Td> <Td> Cough suppressant and topical analgesic </Td> </Tr> <Tr> <Td> Eucalyptus oil </Td> <Td> 1.2% </Td> <Td> Cough suppressant </Td> </Tr> <Tr> <Td> Menthol </Td> <Td> 2.6% </Td> <Td> Cough suppressant and topical analgesic </Td> </Tr> </Table> <Tr> <Th> Ingredient </Th> <Th>% </Th> <Th> Purpose </Th> </Tr>

What is the active ingredient in vicks vapor rub