Complex sentence: Cow Tower formed part of the city defences during the 15th century, with occasional royal instructions given that it should be repaired, and in 1450 St Giles Hospital formally transferred any rights they had to the tower and the immediately surrounding land to the city.
Split into simpler sentences: Cow Tower formed part of the city defences during the 15th century, with the Crown occasionally issuing instructions given it should be repaired. In 1450 St Giles Hospital formally transferred any rights they had to the tower and the immediately surrounding land to the city.