It shall be unlawful for any person to transport any explosive in quantities of more than fifty (50) pounds into or through that portion of the urban county which is bounded by Deweese Street and Rose Street on the east, Spring Street on the west, Second Street on the north and High Street on the south, without a separate written permit to be obtained from the police chief for each such transporting; and it shall be unlawful to transport any explosive in quantities of more than fifty (50) pounds anywhere in the urban county except in a vehicle with springs and with a top and with the sign "Explosive—Dangerous" painted on each of its four (4) sides or carried upon a vertical pole at the front of such vehicle high enough and large enough to be readily readable from both front and rear at a distance of one hundred (100) feet; moreover, if the transportation be at night, such sign shall be illuminated so as to be readily readable from both front and rear for a distance of one hundred (100) feet.