Little
发表于 2025-4-1 03:37:04
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Epidural-Space
发表于 2025-4-1 09:34:16
Introduction,he sense of vision. Smoke signals during the day, and fires at night, have been used in many cultures to transmit warnings about enemy movements, the outcome of battles, etc. For example, it is known that fire signals were extensively used by the armies of the Roman empire .