Categories House Humans Mechanics Sound Effect Tools Air tube & heavy stone movement Post author By redForm Post date June 15, 2020 A millstone maybe ? After grinding that delicious wheat, the remains are pushed through a complicated air tube system. Yes, that’s it ! Download File type: audio/wav File size: 79 KB Length: 0:020 minutes, 2 seconds Bitrate: 353kb/s CBR Tags air, boulder, circular, heavy, line, millstone, movement, pipe, rock, stone, tube