<Table> <Tr> <Td> <Table> Derivation of a wood - tar creosote from resinous woods <Tr> <Td> <P> </P> </Td> </Tr> </Table> </Td> </Tr> </Table> <Tr> <Td> <Table> Derivation of a wood - tar creosote from resinous woods <Tr> <Td> <P> </P> </Td> </Tr> </Table> </Td> </Tr> <Table> Derivation of a wood - tar creosote from resinous woods <Tr> <Td> <P> </P> </Td> </Tr> </Table>

Which gas is evolved on heating calamine strongly in absence of air