18.(Pg. [110]) Are total eclipses of the sun frequent, and when they happen what is their extent?
19.(Pg. [111]) What does this prove respecting the size of the moon?
20.(Pg. [111]) What is shown in [fig. 1, plate 12]?
21.(Pg. [111]) How are lunar eclipses visible, and what is proved by their duration?
22.(Pg. [111]) What is illustrated by [fig. 2, plate 12]?
23.(Pg. [111]) What remark is made respecting those planets which have several moons?
24.(Pg. [111]) What use is made of the eclipses of the satellites of Jupiter?
25.(Pg. [112]) How is the latitude of a place usually found?
26.(Pg. [112]) By what other means may latitude be found?
27.(Pg. [112]) From what is longitude reckoned?