//When I'm aboard the boat I sail at knots per hour.//
Aaargh! Barry, Barry, Barry!
You sail at knots. A knot is unit of speed. It is one nautical mile per hour (which is one minute of an arc at the Earth's equator, equal to 6,076 feet or 1.1508 statute miles).
It is illegal to post mileages on roads in the UK in anything other than miles.
The old 240 pence pound is interesting. It was far more useful than a 100 pence pound. It could be divided equally by 2,3,4,5,6,8,10,12,15,16,20,24,30,40,48,60,80 and 120. 100 pence can only be divided equally by 2,4,5,10,20,25 and 50. Many of the £sd divisions had their own coins: 1d, 3d, 6d, 12d (one shilling), 24d (two shillings) 30d (half-crown) and 60d (the less common crown). There was also a 120d note (ten shillings). These divisions were useful when things were cheaper but less so now as not much costs less than a pound.