Hello again —
Racking my brains, I remembered an old plan I had of Olympic. Checking my archive, I was lucky to find it almost straight away. This may explain something.
On this plan is indicated in colour code ‘buoyancy tanks’ which were ‘added to Olympic’s hull after Titanic’s sinking.’ These tanks follow exactly the layout of the inner skin — and so I assume that buoyancy tanks are just another name for the watertight inner skin, as they were called in the 1910 decade or whenever this plan was drafted. Furthermore, the source states that these tanks were later used during the war to carry oil from North America to England. Considering my (entirely separate) source stating that during the skin’s design consideration had been given to a possible future oil fuel conversion (involving the inner skin being used to store oil fuel), and the general subdivision layout of the skin, it seems entirely likely to me that oil could have been carried (certainly in small amounts) with little modifications. The spring 1917 refit springs to mind, just when America was entering the war, having been angry with Germany since late 1916, or certainly February 1917.
Thoughts?
Best regards,
Mark.