A hybrid of novel-of-ideas and ripping yarn, This Thing of Darkness is more convincingly the latter. The crew's skirmishes with South American natives and a storm off the coast of Uruguay, presaged by wind-blown clouds of butterflies and moths, are beautifully managed set-pieces, pacy, gripping, and vividly chaotic. Counterpointing the action, FitzRoy (the Tory) and Darwin (the Whig) are so neatly oppositional as to appear novelistic conveniences, and Thompson's extensive research seems to have wound up unmediated in their mouths; they talk like text books, so their many discussions are one-note affairs with the same trajectory.
Topped and tailed by suicides, the 600-odd pages of This Thing of Darkness cover 37 years' worth of events chronologically, in a series of precisely dated and located episodes. While the novel's comprehensiveness at times resembles plodding non-fiction - "The seaward cable parted through frost. It froze right through, sir. I had the remainder of the small bower cable on the sheet, and a cable and a half on the bower'' - its prose is generally undemanding, as is the way with clichéd writing: painfully aware or blissfully ignorant, people look daggers, glow with pride, sigh with relief; their grins are impish, their moustaches bristle. If Thompson's tendency to spell out his characters' thoughts saves us from imagining a subtext, it does not make his creations more rounded. For all their musings, many only register as stereotypes, and, as a consequence, few deaths properly haunt the reader. In fact, the most poignant detail is in the book's three-page bibliography. While Darwin's The Origin of Species has been published in many editions, Thompson tells us, FitzRoy's books are difficult to obtain outside the Bodleian Library: one volume still had its pages uncut after 165 years.
A work of mock-Victorian story-telling (albeit with the occasional note of a modern sensibility, as in Darwin's desire to "make a difference'') This Thing of Darkness is an old-fashioned achievement that has more in common with its superannuated hero, Robert FitzRoy, than with the revolutionary Charles Darwin; fittingly so, given its author's evident sympathies.Reuse content