496 
POPULAE SCIENCE EEVIEW. 
have exercised Mr. Campbell’s ingenuity pleasurably to design a number of 
hieroglyphics significant of shape and outline, but it must be confessed that 
the introduction of them is anything but agreeable to the reader. The observa- 
tions in the preface convey some idea of the character of the writer’s 
production : — 
“ The following pages are meant for readers who take pleasure in natural 
science, without being philosophers. They are records of things seen or 
learned, and of thoughts which sprang up while scenes were fresh, or 
knowledge freshly gained ; they are written by one who has no claim to 
scientific knowledge, and they are printed for people like himself. A 
traveller’s book is not for learned professors, but for that vagrant class who 
wander and think for themselves — who think of something besides daily 
bread or daily turtle and champagne, how to get ease and plenty, and how 
to get rid of time.” 
“ Fire ” occupies the least portion of the writer’s book, which may indeed 
be said to be a voluminous popular essay on ice and ice action. We follow 
Mr. Campbell from the Alps to Norway, Scandinavia, Spitzbergen, and 
Iceland, and as we travel with him we pause beside some huge glacier, or 
boulder, or moraine, and listen to his pleasant story of its history and origin. 
In every instance we learn some new fact in physical science, and although 
our teacher has a quaint and somewhat humorous mode of expressing himself, 
still his power, as an instructor, is all the greater from this circumstance ; 
for we cannot listen without remembering his words, and as we accompany 
him on his wanderings we “ cannot choose but hear.” Let us see how he 
illustrates the action of icebergs in producing deposits of gravel, such, for 
example, as those of the Somme valley : — 
“ A plate of ice, loaded with sand and loose stones, must drop its load in 
the same way whatever its dimensions may be. In a small plate the ice 
gradually melts, and mounds of sand form themselves into conical heaps on 
the wet surface. But as the ice-raft melts it loses its power of flotation, 
and it becomes lop-sided ; one edge sinks and the flat surface becomes a 
sloping plain. It slopes more and more as the ice melts, till the slope becomes 
so great that the deck-load slips and rolls to one side and sinks the sunken edge 
still more. Then the mounds slip and become avalanches, slide overboard, sink 
to the bottom, and become mounds there. But while rubbish is shot one way the 
float shoots in the opposite direction, and the rest of the deck-load is washed 
overboard as the raft slips through the water. Ice, relieved from weight, 
bobs up like a board and shoots off edgeways, because there is least resistance 
in that direction. When rubbish-heaps are thus shot eastward, flat ice shoots 
westward, and the rubbish at the bottom is deposited as a mound with a 
tail stretching westward.” 
English, Irish, and Scotch glacial geology also receive Mr. Campbell’s 
attention, and his observations on this branch of his subject should be 
carefully read by scientific tourists. The publisher deserves much praise for 
the excellent manner in which the volumes have been executed, both in 
regard to printing and illustration ; the binding is quite peculiar, the covers 
being so arranged that they exhibit, in “ relief,” the ice-markings which are 
seen upon certain rocks in St. John’s, New Brunswick. 
