Whoever shall secrete, sell or dispose of, or offer for sale, or purchase, knowing the same to be such, retain after proper demand is made, or in any manner pawn or pledge, any military property, which shall have been issued under the provisions of this article, shall be guilty of a misdemeanor, and, in addition to the punishment provided for misdemeanors in this article, shall forfeit to the state twice the amount or cost of the property so secreted, sold, disposed of, offered for sale, or purchased, retained after proper demand has been made, pawned or pledged.