Anyway, the television adaptation, while also enjoyable and perfectly acceptable, provides a great illustration of the difference between what works in literature and what works on the screen. Particularly so since the novel was adapted by no less than Boyd himself, and it's hard to imagine a more considerate treatment to its pages. Further, it's also been allowed the luxury of spreading out across more than four and a half hours (= six hours subtract adverts).
The most obvious departure is that the novel's narrative structure, essentially a long succession of diary entries written by the steadily changing character of Mountstuart across the span of his life, evaporates into merely a long chain of events. Inevitable really, given the translation to a visual medium, but in doing so Mountstuart becomes less a fleshed-out character and more an alternative Zelig, with walk-on parts throughout 20th century history. Oddly, I'd argue that it still works, but more as a separate dramatic work than an adaptation.
Another departure is that, even with its extended runtime, the television series is forced to significantly abridge the novel. This has left quite a few interesting portions on the cutting room floor, but even then the portions that survive are heavily abbreviated. Not so much, or so significantly, in plot, but more in character. Mountstuart's friends, lovers and rivals, all living, breathing characters in the novel, are reduced here to brief appearances that lose much of what made the novel significant (at least to me). Almost to the extent that the critical departures of Mountstuart's second wife, Freya, and of his son, Lionel, lose almost all of their impact. Boyd does what he can to make these losses appear powerful on-screen, but there's only so much that he can do.
Anyway, as someone used to disappointment in the translation of favoured works to the screen, this is very far from disappointing. I think that Boyd has done as good a job as he could, but has wound up with something quite different to his original literary effort. It's certainly engaging enough that I'll bet it turns many people onto the novel, and that's no bad thing. In fact, should I ever diminish the vast stack of birthday/Christmas tomes, I might be one of them.