FEBRUARY 25, 1897] 
NATURE 
393 
organisms, will explain a flat floor, without bringing in 
the action of the sea at considerable depths. In a sub- 
siding peak with a barrier reef, there cannot be sufficient 
wave-action to level a large lagoon. In a bank rising 
by growth, why should it become level over its whole 
surface? 
A further point remains. Can coral settling on a bank, 
30 fathoms or so beneath the surface, form an atoll? 
Mr. Darwin limits this possibility to “some fathoms sub- 
merged,” and considers that “it is an assumption with- 
out any evidence that at a depth at which the waves 
do not break, the coral grows more vigorously on the 
edges of a bank than on its central part.” 
I think that the experience of the years since Mr. 
Darwin wrote that, has given us evidence that this is not 
an unwarrantable assumption. 
The instances of shallow narrow rims, or of isolated 
patches of coral on the edges of such banks, are now 
innumerable. 
It is so well recognised that the edge of such a bank 
is the place to expect shoal patches, that in carrying out 
hydrographic surveys in coral regions it is the edge that 
is most minutely searched. On such edges are found 
evidence of coral colonies in every stage; complete 
ridges, broken ridges, and mere patches here and there. 
Always, where means have permitted, is evidence 
brought up that such colonies are alive. There may be 
dead rims, but they are the exception. 
The fact ofa current, whether tidal, or otherwise 
induced, being accelerated on meeting a submarine bank 
is, I think, sufficient to account for this. The water 
pours over the edge of the bank, and brings abundance 
of food to those corals which settle on it, to the dis- 
advantage of those settling further in. 
The phenomena of coral patches and ridges on the 
edge of these submerged banks is so frequent, that I know 
not how they can be otherwise explained. The great 
Seychelles Bank is lined all round its edge, so far as 
examined, with such coral ridges and patches. The 
small islands, in this case of primary rock, in the centre 
of this bank are lined with fringing reefs; and if the 
whole bank, 150 miles in length, has uniformly sunk, they 
must have sunk too, and the fringing reefs would be 
beneath the surface. 
Given these edgings of vigorous living coral on sub- 
merged banks, of which I consider we have indisputable 
proof, they will certainly grow to the surface and form 
the complete atoll. In the earlier stages calcareous 
organisms of all kinds will settle all over the bank, giving 
it a coating more or less thick according to circumstances. 
The only other point that need be mentioned is the 
steep slope that characterises some atolls. As to this, I 
believe that masses with irregular projections like broken 
coral, falling down in water, will entangle themselves, and 
lie at a steepness of slope unknown in similar falls on 
mountain sides, and though the aid of subsidence may be 
needed for the almost vertical walls which occasionally 
occur, that the slopes of most atolls can be explained 
without it. 
There seems no necessity to call in the aid of Murray’s 
theory of deepening and widening of the lagoon by 
solution, but I am not contending that it may not so act. 
What I am concerned to show is that without it, and 
without subsidence, deep and large atolls may be formed, 
and that we have abundant evidence of atolls so forming. 
I am not arguing that there has been no subsidence ; 
indeed, I think that a volcanic cone, from the nature of 
its loose material, will frequently subside, and that some 
of the deeper lagoons may owe their depths of 50 
fathoms or so to such a movement, quite apart from sub- 
sidence of large areas which we know occurs. Nor do I 
say that volcanic mounds that have failed to reach the 
surface, may not be built up toa sufficient height for 
corals to flourish ; nor that all foundations and atolls 
NO, 1426, VOL. 55 | 
have been formed in the same way; but I put forward 
the hypothesis that the cutting down of volcanic islands. 
by wave-action and currents, has had a greater share in 
providing suitable bases for coral atolls than any other 
process of nature. 
I may further suggest, in defence of my views, that it 
tends to explain why, over vast groups of atolls, no central 
summit is left. W. J. L. WHARTON. 
FRIDTJOF NANSEN’S “FARTHEST 
NORTH.” + 
WHEN Gerrit de Veer published his “True and 
4 perfect description” of Barents’ voyages for the 
discovery of a North-east passage, “so strange and 
woonderfull that the like hath never been heard of 
before,” he justified himself for doing so by several 
reasons :— 
“And also to stoppe their mouthes, that report and 
say, that our proceeding therein was wholly unprofitable 
and fruitelesse ; which peradventure in time to come, 
may turn unto our great profite and commoditie. For he 
which proceedeth and continueth in a thing that seemeth 
to be impossible, is not to be discommended ; but hee, 
that in regarde that the thing seemeth to be impossible, 
doth not proceed therein, but by his faint-heartedness 
and sloath, wholly leaveth it off.” 
This might not inappropriately be taken as an apology 
for Nansen’s popular account of his great Arctic journey, 
which in many ways finds its nearest prototype in the 
classic adventures of the Dutch explorers three hundred 
years ago, when the lifting of a ship on the ice without 
being nipped was first observed, and the nature and 
effects of ice-pressures were first clearly described. For 
an example of a Norse Arctic explorer visiting England 
and receiving a Royal welcome, we must go back a 
thousand years to the time when King Alfred entertained 
Othar, and gave in a gloss on his Orosius the first record 
of Arctic discovery ever written in the language of the 
English. But between the visits of Othar and Nansen 
the progress of Arctic discovery has been due mainly to 
our countrymen, who have purchased with their lives 
much of the experience on which the safe and successful 
voyage of the yam was planned. 
These large and handsome volumes, giving the full 
narrative of the vpyage, have been very rapidly prepared, 
too rapidly for the careful reader, who has been sacrificed 
to allow the eager public to revel in a story of adventure- 
More leisurely preparation might have left the book no 
less readable, and made it much more valuable, 
by including at least a few preliminary reports on 
the results of the voyage which must necessarily be 
of “great profite and commoditie” in many branches of 
knowledge. The revision of the text might have been 
more complete, the cumbrous title-page might have as- 
sumed a pleasing form, there might have been a pre- 
fatory note acknowledging the author’s debt to the 
translators, whose work certainly deserves recognition, 
and the maps might have been of a less provisional 
character. Scientific readers will, however, be content 
to await the full discussions by specialists, which are 
doubtless in preparation, and meantime they cannot dip 
into the narrative of the most successful of all Arctic 
voyages without becoming absorbed by its peculiar 
fascination. The glamour of the Arctic regions has been 
felt by almost every explorer, and not a few have suc- 
ceeded in passing it on to the readers of their books, but 
none so perfectly as Dr. »Nansen. Too often the tale 
1 Fridtjof Nansen’s ‘‘ Farthest North,” being the Record of a Voyage of 
Exploration of the Ship Avazz, 1893-96, and of a Fifteen Months’ Sleigh 
Journey by Dr. Nansen and Lieut. Johansen. With an appendix by 
Otto Sverdrup, Captain of the vam ; 120 full-page and numerous text 
illustrations, 16 coloured plates in facsimile from Dr. Nansen’s own sketches, 
etched portrait, photogravures and maps. 2 vols. Pp. 1200. (Westminster = 
Archibald Constable and Co., 1897-) 
