Prime responsibility for the celebrated spinwheel, which is largely individual and instinctive, rests with the Garrison Sergeant Major. A 'wheel' is not an easy manoeuvre with even a small body of troops, and with a block of 400 men the normal wheel is impossible. The massed band therefore pivots on its own centre, so that certain outer ranks and files march long distances in a hurry while the centre and inner ranks loiter with extreme intent, or merely mark time. Yet others not only step sideways but backwards as well. This highly complex movement is called a 'spin-wheel', the details of which can be found in no drill book or manual of ceremonial. Its complexity defies description, and if the truth were known, many of the participants know not whither they go or, on arrival, how they got there. The spin-wheel is almost an art form and each performance of it, although similar in essentials, is different in detail. Most of the performers are adjusting their actions to suit the needs of the spin-wheel of the moment, having adjusted their movements quite otherwise on other occasions.