"It was a figure of Father Time"
Father Time is a figure drawn together from many mythologies and roots. He is usually depicted as an elderly man in a long cloak, often carrying a scythe and an hourglass. The skull in Ma Nelson's version associates him still more closely with the figure of death, and suggests a view of time as the inevitable destroyer of life.
The Rotunda Clock at the Library of Congress Building in Washington DC, created by John Flanagan, depicts a central figure of Father Time with a scythe and hourglass. He is flanked by mythological and Zodiacal figures, and students deep in books.