At first, the sea was formed around 5.6 million years ago, due to a large-scale flood, but the waters were separated from the Atlantic Ocean by the Strait of Gibraltar, so, in the hundreds of thousands of years that followed, the water spreads dried out almost completely.
The Irish Punt was legal tender in the Republic of Ireland until 2002, when Ireland joined the Euro. This guide outlines the sources for historical exchange rates between the Irish Punt and Pound Sterling. The Irish Punt established by the Currency Act 1927 had a fixed link with Pound Sterling until March 1979.
In the aftermath of the Panic of 1857, funds continued to be tight, and at one point Drake was forced to borrow from local businessmen to keep the project in operation. On 27 August 1859 workers had driven a pipe down to a depth of 69.5 feet and left for the weekend.