And since it is well to study by proceeding from the known to 

 the unknown ; to make ourselves thoroughly acquainted with 

 that which is tolerably familiar to us, so that we may the better 

 comprehend that which is new and strange ; let me briefly describe 

 the modern Nautilus and its shell, which so much resembles the 

 ancient Ammonite. The Nautilus shell is doubtless a familiar 

 object to you all, but in all probability you never cut one open to 

 examine the interior, perhaps would have rejected the suggestion 

 with scorn, as such a mode of acquiring knowledge is supposed to 

 be peculiar to children in their treatment of mechanical toys. 

 Nevertheless it is a wise proceeding. 



But first of all, let me ask you to look upon this modern Nautilus 

 with that respect and reverence which is due to the descendant and 

 representative of an old historical family. I remember reading of 

 some geologist (I believe it was Murchison, but am not sure), who 

 on exhibiting a certain ancient fossil to a friend, said, " Handle it 

 reverently; maybe it is one of the first created things." I might 

 almost say the same of this. Like the Gairfowl on the Allalone- 

 stone in Kingsley's Water Babies it "is of an ancient clan," and 

 might say with that grand old lady, " I am the last of my family." 

 I'or the Nautilus is found fossilized as low down as the Upper 

 Silurian, and some of its close relations lower down still. Those 

 who have read geology know what that means. And it has lived 

 on ever since, well nigh unchanged, though the long vicissitudes of 

 Time, and now wanders through our seas, solitary and without 

 kin. By its aid we shall gain an insight into the nature of our 

 Ammonites. 



Well, notice this interior, which one of my students has so care- 

 fully cut for me. You would not have expected to find these 

 chambers within, so neatly, smoothly, and symmetrically separated 

 from each other- There are in this specimen 33 compartments, 

 and nothing could exceed the gracefulness of the curves by which 

 one is completely isolated from the other. You might almost 

 imagine that each cell had been the abode of a separate creature, 

 and that the whole shell was a kind of colony or model lodging- 

 house. (And let me remark just here that the interior of many 

 other shells would surprise you just as much if you examined them ; 

 one or two are on the table, though they have no connexion with 

 the subject of our lecture). 



Now notice the enormous size of the outer compartment ; in that, 

 and in that only the animal lived ; the others were simply air- 

 chambers which assisted the occupant of the shell in its movements 

 through the waters. Of course originally the first compartment 

 at the centre of the spiral was the habitation of the nautilus ; it 

 enlarged its dwelling as its body increased in size ; and as it built 



