Books like The Emperor's Silent Army
Jane O'Connor
The Emperor's Silent Army is 48 pages, about 53 minutes at 250 words a minute.
7 books to read next
How long each takes
Archaeologists Dig For Clues 35 min 
The Magic School Bus Shows and Tells 39 min 
The Riddle of the Rosetta Stone 1.6 h 
Tut's Mummy 51 min 
World's Most Amazing Lost Cities 35 min 
Pyramid 1.3 h 
The 5,000-Year-Old Puzzle 45 min Bar height shows length. Estimated at 250 words a minute.