In The Seven Crystal Balls (1948), Seven scientists mysteriously fall into a profound state of lethargy. As Calculus has disappeared,Tintin and Captain Haddock set off in search of the Professor.
Series: Adventures of Tintin (Paperback)
For Ages: 10 - 13 years old
For Grades: 5 - 8
Number Of Pages: 62
Published: 30th September 1975
Dimensions (cm): 29.5 x 21.9 x 0.3
Weight (kg): 0.25