The building and mechanism required repair in the 1850s. The custodian and a clock technician wrote a technical brief about the state of the Clock Tower and the repairs they deemed necessary to complete. Luigi De Lucia was tasked with making these repairs. Also, a committee asked him to figure out a way to show the time in the dark. De Lucia decided to use illuminated panelled wheels that display the time in five minute intervals. This addition was one of the first tower clocks that used a digital format. Image By Tony Hisgett from Birmingham, UK (Clock Tower St Mark's Square 3  Uploaded by tm) [CC BY 2.0 (http://creativecommons.org/licenses/by/2.0)], via Wikimedia Commons