The light in CROOKS' room is "meagre". This suggests the lack of happiness and hope CROOKS holds - represented through his room's dismal (dark) description. This shows that the light tries to get input never manages to penetrate the darkness.
This statement means that books are a tool that have the ability to take carry you to another world as a car takes you to somewhere physical, a book lets your mind wander to places in your imagination.
