A distance estimated in fathoms between successive marks on a sounding line.
A distance estimated in fathoms between successive marks on a sounding line.
水砣绳间距标示通过测深锤上连续的标记估计出来的以英寸计量的距离
A distance estimated in fathoms between successive marks on a sounding line.
水砣绳间距标示通过测深锤上连续的标记估计出来的以英寸计量的距离