 Complete the following phrase:  Attached to the various types of fusilier headdress, including the modern beret, is the hackle. This is a short cut feather plume, the colours of which vary according to the regiment. Initially, the only regiment authorised to wear a plume or hackle were the 5th of Foot Northumberland Fusiliers. The regiment had originally worn a white feather distinction, authorised in 1824 to commemorate the 