Part,  Chapter

 1      I,  XIII|              American continent by an isthmus, extending from the lower
 2     II,  I   |         change in their latitude. The isthmus—that is to say, the neck
 3     II,  I   |               south, where the broken isthmus was situated; but from their
 4     II,  I   |              by means of its flexible isthmus with the American continent.
 5     II,  II  |              a sea-horizon, where the isthmus connecting the peninsula
 6     II,  II  |              fracture was made at the isthmus itself, so that the whole
 7     II,  III |          which was most likely at the isthmus itself, ought to be examined
 8     II,  III |             before the rupture of the isthmus.”~“The birds will, however,
 9     II,  III |        effected by the rupture of the isthmus.~Formerly the south-western
10     II,  III |            the long resistance of the isthmus, which nothing but some
11     II,  IV  |          point of rupture. It was the isthmus which had yielded in the
12     II,  IV  |             since the breaking of the isthmus. Long, in obedience to the
13     II,  V   |             ice at the part where the isthmus had been broken off; told
14     II,  V   |             since the fracture of the isthmus, or rather since the last
15     II,  VI  |            was still connected by its isthmus with the mainland.~But the
16     II,  VI  | re-established by means of the broken isthmus; it was, therefore, imperative
17     II,  X   |             as stationary as when the isthmus connected it with the mainland.
18     II,  XII |              the earthquake broke the isthmus, and converted the districts
19     II,  XII |              the earthquake broke the isthmus, and converted the districts