El "vidrio lento" es un cristal que absorbe poco a poco la luz de los sucesos que ocurren delante de él, los cuales resultan visibles meses o años después.
A partir de esta idea, Bob Shaw construye una excelente y a la vez original novela. La profética visión de lo que podría ser un invento de estas características y la problemática social de su uso, desde el crimen casi perfecto hasta la verificación por parte de la justicia al cabo de cinco años- hacen de esta novela una obra maestra de ciencia ficción en el mas puro sentido de la palabra.

This is really fascinating to read from a modern perspective - as always with older scifi, some of the missed opportunities are a little jarring (glass contact lenses!) but (as is often, if not always, the case) the overall predictions are eerily accurate. An interesting take on the development of the surveillance state. ( )

Bob Shaw's story "Light of Other Days" (1966) is one of the great classics of science fiction. In a mere ten pages or so, it succeeded in introducing a brand-new concept to sf (a rarer even than many of us would like to think) while also generating a genuine and very poignant feeling of empathy for its central character (who is not its narrator). A squabbling couple are driving through the Scottish Highlands when they come across a slow-glass farm. Slow glass is a crystalline structure through which (to simplify) light passes very slowly; it can thus be used to observe past scenes. The "farmer" is allowing sheets of the stuff to absorb the light from the spectacular local countryside so that purchasers can take them home to watch those scenes over the months and years to come. As the couple haggle with each other, a young woman and an infant watch them from time to time from the farmhouse window. By story's end they discover that these are the farmer's wife and child, killed six years ago by a hit-and-run driver. The slow glass in his window is preserving for him the illusion that they're still alive. But for how much longer?

Shaw published two more slow-glass stories, both good though neither as powerful as the first: "Burden of Proof" (1967; a barbaric judge sentences a convicted murderer to die even though in five years the proof of the man's innocence may emerge on the far side of a pane of slow glass) and "A Dome of Many-Colored Glass" (1972; a sadistic Chinese official torments a prisoner by fixing to his eyes slow-glass modules containing footage of Western atrocities like My Lai). There was also a late and very different addendum to the corpus: "The Edge of Time" (1979), co-authored with Malcolm Harris and published in an anthology edited by yours truly, Aries 1. Here the conceit is that there are not one but two time dimensions, Presence and Change, and that what's really expanding in our expanding universe is the Change dimension. Serflike pilots take investigatory craft to the boundaries of this bubble, and flirt with the skin of the time so as to send back scientific data. One of these pilots, his instruments destroyed by sabotage, uses the onboard slow glass cunningly in order to plot his way home -- or so, at least, he thinks.

Back in those days, if you wrote a successful series of stories, the next thing you did was construct out of them a novel -- or a "fixup", as the Clute/Nicholls Encyclopedia of Science Fiction somewhat ungraciously called this mercenary literary form. Shaw's slow-glass fixup, Other Days, Other Eyes, was one of his clumsier efforts. The three primary stories are thrown in as interspersed "sidelights" and have nothing aside from slow glass in common with the rest of the plot, which sees Al Garrod, the inadvertent inventor of slow glass, transform himself into a plutocrat industrialist while developing new techniques to enhance the stuff's versatility and usefulness. In the process he must deal with his bitch wife, solve two pretty implausible murder mysteries (only one of which involves slow glass, finally bring a somewhat gauche and jejune extramarital romance to its consummation, and in general fill enough pages for the publishers to market this as a full-length novel. This framing material does take the opportunity to fix a few technical glitches with the original concept (such as explaining why light passing through the slow glass at an angle doesn't take perceptibly longer to reach the other side), but it almost entirely ducks until the very end the practical and ethical problems generated by the introduction of any widespread means of looking into the past -- the havoc of suddenly creating the ultimate surveillance society, as envisaged by Isaac Asimov in his 1956 novella "The Dead Past" and vastly expanded upon by Arthur C. Clarke and Steve Baxter in their 2000 novel The Light of Other Days. Towards the end of Other Days, Other Eyes there's a nod to this concern via occasional mention of a vigilante-style Privacy League, which runs around throwing bricks through slow-glass windows; but it's only in the final pages, when Garrod discovers the government has been spraying the entire nation with slow-glass dust so that no longer can anything at all be kept secret, that Shaw properly acknowledges the fell purposes to which his "invention" could be put.

There are occasional moments of high silliness. The bitch wife, who stupidly blinds herself by refusing to obey Garrod's instructions to make herself scarce from an experiment that's about to blow, is given a replacement form of sight in the form of (essentially) contact lenses made out of slow glass: this way she can see again, even if everything she sees is a day or two late. (Watching TV involves a ludicrously elaborate palaver in order to record the soundtrack and synchronize it with her watching.) But if that technique can be made to work, I hear you cry, why not simply make the lenses out of ordinary glass, so she could see everything in real time? It's not a question I can answer.

Shaw was rarely if ever a tedious writer, so the pages of Other Days, Other Eyes kept turning rapidly enough, but here he seems to be bored -- as if writing the fixup was not something he actually wanted to do, but undertook merely in order to keep agent, publisher and bank manager happy. I wonder if he had his tongue firmly in his cheek when writing about the slow-glass contact lenses; was he testing to see if his publisher would notice the illogicality? There's a surprisingly smutty sex scene that seems there primarily to keep the writer's interest from flagging, and here's the moment when Garrod has the flash of insight that enables him to solve the first of the two murder mysteries:

His knees felt loose, his heart had lapsed into an unsteady, lumping rhythm, and a chill extended downward from stomach to groin. In his head there was a pressure which rapidly built up to a peak and exploded in a kind of psychic orgasm. (p96)

It never happened to Ellery Queen quite like that, I'm pretty sure. ( )

I really enjoyed this book. I had previously read the short story about slow glass (Interlude I). The main novel has no plot connection to the three interludes. I particularly liked the detail and the depth of consequences to which Shaw carried the idea of slow glass.

Un altro grande romanzo di Bob Shaw incentrato sull’ossessione del “Vedere”. Il “vetro lento”, un vetro che può trattenere la luce anche per molto tempo. È in grado di “rallentare la luce”, in altre parole i raggi luminosi che lo attraversano impiegano qualche frazione di secondo in più, quanto basta per creare un ritardo nella visione esterna. Tutto bene? Fino a un certo punto, perchè il vetro lento consente di spiare la gente, perchè funziona verso l’esterno ma anche verso l’interno. Montando un vetro lento in camera vostra per un mese e poi smontandolo sarà possibile vedere poi tutto quello che avete combinato in camera in quel mese. Intercettazioni telefoniche, echelon, grande fratello, diritto alla privacy...l’umanità si abituerà anche a questo. Probabilmente anche noi siamo attesi da altri giorni e dovremo imparare ad avere altri occhi. Di Bob Shaw Vittorio Curtoni ha scritto: « è uno dei pochi autori capaci di usare con creativa autorità la lingua inglese: la sua sintassi è complessa, armoniosa, costruita su scansioni di ricchezza insolita; il suo lessico è preciso, netto, direi quasi fotografico, del tutto lontano dalle vaghe imprecisioni che una lingua sintetica come l’inglese permette (anzi, stimola) »