the messenger could enjoy some degree of protection from those who would kill him and steal the scroll. Attaching messages to arrows fired over a castle's walls was a common method of communicating with allies under siege. While the message was often simply wrapped around and tied onto the arrow, some used special arrows with hollow shafts specifically designed for this purpose. Whistling-bulb arrows, originally used just before a battle to draw the attention of the kami that they should watch the events about to transpire, were modified to serve as message-carrying arrows. References Turnbull, Stephen (1998). 'The Samurai Sourcebook'. London: Cassell & Co. Turnbull, Stephen (2002). 'War in Japan: 1467-1615'. Oxford: Osprey Publishing. Military history of Japan Samurai weapons and equipment Japanese heraldry