Book,  Chapter

1        I,  XXIV|     his instruments, and the blackboard which had served for his
2       II,  I   |  figures on his extemporized blackboard. The handwriting corresponded
3       II,  I   | papers already received; the blackboard was covered with algebraical
4       II,  II  |   ancient globe. “Where’s my blackboard, Joseph?”~“Quite safe, sir,”