of devoting undivided attention to new objects of
interest; sliip-life is generally unfavourable to steady
Avork, and during a great part of the time the motion
of the ship makes it impossible to have even the
limited space at one’s command in his cabin, litterel
Avitli papers and journals and memoranda in the
orderly confusion wdiich is inseparable from comfortable
literary w'ork. Although there wns a reference
library on board the ‘ Challenger,’ excellent under
the circumstances, it tvas of course by no means
complete enough to enable us to go with safety into
matters of detail. Still, nottvithstanding these difficulties,
it seemed to me so desirable that a sketch
of our proceedings and of the more important results
of the Expedition should be made public at as early
a date as possible, that I determined to make the
attempt.
At first I hoped that it might have been possible
to make the publication of the journal almost keep
pace Avith the voyage, or that at all events the rough
results of one year’s Avork might have been published
during the next, and accordingly a great part of the
first volume Avas written and put into type during the
year 1874. I found, however, that this was impracticable
; the uncertainty of communication became
greater as the voyage proceeded; and inevitable
delays having occurred, further observations constantly
made it necessary to modify previously formed
opinions, or desirable to strengthen them by additional
eAudence.
AVe arrived in England on the 24th of May, 1876,
Avith the rough journal of the cruise in a sense
complete, but not in a form for publication. Erom
the amount of AVork thrown upon my hands in
getting the collections into order, and having arrangements
made for the working out of the scientific
results, the difficulties in the wmy w^ere even greater
than they had been on ship-board ; and now, nearly
a year after our return, the first two volumes only
are completed.
In a former volume^ I have given a general history
of deep-sea investigations. I have described
with some minuteness the appliances and methods
employed during the preliminary cruises of the
‘ Lightning ’ and ‘ Porcupine ’ in ascertaining the
exact depth, in taking bottom and intermediate
temperatures, and in determining the distribution
of the deep-sea fauna by means of the dredge; and
I have stated the general conclusions on various
questions to which w^e were at that time led by the
study and generalization of our results. Although
the additional experience which Ave have now gained
has caused me to alter my views on one or two important
points, I adhere in the main to the opinions
and statements contained in that book, and to save
unnecessary repetition I shall regard ‘The Depths
of the Sea’ as a general introduction to the series
of volumes giving an outline of the ‘ Challenger ’
Circumnavigating Expedition.
This last undertaking was on a very different
scale from the trial cruises of the gun-boats, and
^ ‘ The Depths of the Sea.’ Second Edition. Macmillan and Co.