The Lanternarius at the Baths of Diocletian.

Lanternarius with cucullus - I-II century A.D.
Rome Tiber, Palatine bridge.
National Roman Museum (Baths of Diocletian)
Michelangelo's Cloister.

A little mysterious statue rests in the shade of the cloister in the National Roman Museum (Baths of Diocletian).  Among hundreds of statues of the Imperial age, it would easily risk to go unnoticed if it were not for the seductive charm it emanates, a sense of peace, an aura of mystery.  
Rather than statues of emperors or victorious generals,  those 'extras', background actors in history, have much more to say about daily life back then:  a little boy, a slave, holding a lantern, fallen asleep while waiting for his master.  It's chilly outside and the lanternarius is wrapped in his cucullus, a rough hooded jacket. 

Streets had no public lighting, except when shows were held at night at the circus or amphitheater. 
Therefore to venture out it was necessary to have a torch or a lantern, perhaps carried by a slave (lanternarius).  Especially in the heavy and noisy night traffic.
Caesar in fact in 45 b.C. prohibited the circulation of carts and chariots during the day (Municipal Julian Law), except to transport building materials for great public works.

The cucullus, later adopted also by medieval monks (and by the likes of Yoda in Star Wars) was the work coat used by Roman slaves:  just as the toga was worn by  Roman citizens so the cucullus was indicative of a slave, who needed to be outside in bad weather. 

The cucullus is the ‘cloak of invisibility’ associated also with the underworld and the most renowned cucullatus divinity of Hellenistic antiquity is Telesphorus (god of sleep):  a hooded, cloaked, barefoot child-god, venerated also in association with Asklepios, the healer god who visits patients at night.  Thus often on tombs similar funerary statuettes illuminated the path of the dominus through the darkness of death.