Phil Collins's piece They Shoot Horses - in which a group of Ramallah teenagers bop themselves to a state of exhaustion to a soundtrack of Western pop songs - accounts for a staggering seven hours of that total, but there are plenty of other pieces which do their bit, too. And if you think I should have better things to do with my time than work out just how much time it would take to watch these things - well, I'm inclined to agree with you, but the train had come to a stop somewhere outside Darlington, the view out of the window was uneventful even by the exacting standards of video art, and my mind started turning over the question of boredom and its uses.
Nobody ever would watch all the video pieces all the way through, of course - and several of them, not just the Collins piece, seem expressly designed to make sure that they will outlast your attention span. The point is to enter the room and leave the room with no notion of when they began or when they will end. But there are others that can't help but raise the question of the relationship between the running time and the artist's intention. An artist called Anna Barriball has a video work called Projection. It consists of a static, framed, shot of the artist standing in a sunlit window. At least four fifths of the screen are filled with the wall of the room, onto which spangles of reflected light are thrown by sequins on the artist's T-shirt. They move gently as she breathes. It runs, the label asserts, for five minutes and 54 seconds. Why, exactly? It can't be that this is a guess as to how long it will take the average viewer to get what's going on. With that helpful nudge from the title you should be able to gather the essential elements of the piece within about 20 seconds. One assumes, too, that this is an arbitrary running time, rather than a precisely calculated one. The piece wouldn't be substantially different if it was 30 seconds longer or shorter. The subversive thought occurs that five minutes and 54 seconds may mark the point at which the artist got bored with her own creation and simply couldn't be bothered to carry on. But the crucial thing is that boredom isn't an unwanted side-product of this work - it's one of the materials from which it is made.
The video artist Tacita Dean acknowledged something like this recently when talking about her own work, which has made its own substantial contributions to spectacular inertia (she made a 44-minute film in a revolving restaurant in which almost nothing happens). In an approving piece about her art, the novelist Jeanette Winterson quoted her as saying: "I do not think I am slowing down time, but I am demanding people's time." The demand for time really isn't the significant thing though. A Vin Diesel action movie does as much, and usually asks for considerably more than Dean does. What she really meant was that she demands time for things people don't really think it's worth spending time on. The mismatch between their expectation of what a film or television screen usually does for them, and what this screen is doing, is the point. And another name for that mismatch would be boredom, which we are expected to endure with stoicism in return for an unspecified reward. Those who think the pay-off will come as an explanatory flurry of action - just as some minimalist music will suddenly break its repetitions for an overwhelming flush of melody - are almost always disappointed. Most video artists don't want to distract the viewer from the morally instructive tedium of their images.
The obvious problem with this is that it can be a very time-consuming business telling the difference between good boredom and bad boredom. This is one reason why video art can feel so presumptuous and diva-like, so queenily demanding, to use Dean's word. It has to have its own room, it insists on being the centre of attention, and it doesn't care that there are 49 other artists waiting and your time is short. Sometimes you long for a curatorial Mr Bennet to step in and say: "You have delighted us long enough". At other times you emerge on the other side of boredom into a richly unfamiliar world. But at all times I think that old adage about culture risks acquiring a tetchy, impatient undertone: life is short, art is long.