On the transfer in the register, whether on sale or otherwise, of colonial stock to which this Act applies, there shall be charged in lieu of any other stamp duty, a stamp duty of two shillings and sixpence for every full sum of one hundred pounds, and also for every fraction less than one hundred pounds, or over and above one hundred pounds or a multiple of one hundred pounds, of the nominal amount of stock transferred:
Provided that a transfer made for effecting the appointment of a new trustee shall not be charged with any higher duty than ten shillings.