Any person subject to this Act who attempts to commit any of the offences specified in sections 34 to 64 inclusive and in such attempt does any act towards the commission of the offence, shall, on conviction by court-martial, where no express provision is made by this Act for the punishment of such attempt, be liable,
     if the offence attempted to be committed is punishable with death, to suffer imprisonment for a term which may extend to fourteen years or such less punishment as is in this Act mentioned; and
     if the offence attempted to be committed is punishable with imprisonment, to suffer imprisonment for a term which may extend to one-half of the longest term provided for that offence or such less punishment as is in this Act mentioned.