The writers themselves commented - If the sea bottom , which is in very few parts as much as 20 fathoms deep , were elevated , the island of Alderney , the Burhou and Ortac group , and the Casquets would be connected by low land , and form a narrow island around long .
The writers themselves commented - If the sea bottom , which is in very few parts as much as 20 fathoms deep , were elevated 120 feet ( 37 m ) , the island of Alderney , the Burhou and Ortac group , and the Casquets would be connected by low land , and form a narrow island around 12 miles ( 19 km ) long .