'The experience of looking at a pair of lips 20ft wide, at the downy hair in the tender ditch beneath the nose, the way lipstick can flake and smear, is a privilege of this cinematic century'

The news, earlier this week, that Warner Brothers are going to build more multiplex cinemas in Britain was generally welcomed as evidence of the renewed health of the industry. The graph at the bottom of the patient's bed has turned upwards, after a long period in which no cure seemed available for the slow haemorrhage of cinemagoers. But if it's good news for the industry, it's may be bad for the medium. I found it distinctly depressing myself, a melancholy that was accentuated this week by going to see Waterworld at the Empire, Leicester Square - one of the old breed of cinemas, where the screen doesn't put you in mind of a bedsheet tacked to the wall of a youth-club hut.

It wasn't that Waterworld itself offered much of a hymn to the virtues of size. Quite the opposite in fact - the film might be an object lesson in how to dissipate the thrills of massive scale. Part of its problem is unavoidable - 200 square miles of sea look pretty much the same as one square mile and there was never going to be a way the movie could awe you with the extent of its imagined flood. On a hazy day even the English Channel can do a passable imitation of global inundation. But at the same time this is not a film that knows much about the spectacular, about the pleasures of size. Apart from a couple of cheesy shots, in which Costner's boat is framed against a huge moon, it doesn't use scale to any great effect. It's clumsiness does prompt the thought, though, that the cinematic experience of size is a unique aesthetic experience, one which can't help but be threatened by the viral spread of the multiplex.

Of course other art forms are drawn to bigness too, but the attraction is often a hazardous one. Giganticism in sculpture and architecture is rarely a tender or intimate thing, as it can be in a cinema. And when the theatre aims at effects of size it can't escape from the inflexible corporeality of the actors. One of the most dramatic stage settings I've ever seen was for the Schaubuhne production of Eugene O'Neill's The Hairy Ape (seen here at the National) in which the proscenium was filled by a wall of steel, the side of the ship on which the drama takes place. The effect was wonderful, placing the action, startlingly for a theatre, on a vertical plane rather than a horizontal or inclined one. But the whole point was to dwarf the principal characters, servants of this colossal machine. Cinema is alone in being able to enlarge the human without losing humanity, which is why a cinematic star has an impact on our imaginations quite unlike a great stage actor or actress.

And the experience of looking at a pair of lips 20ft wide, really looking - at the downy hair in that tender ditch beneath the nose, at those fine vertical creases, at the way lipstick can flake and smear, at the transition from dry to wet - is a special privilege of this cinematic century. What's special about the enlarged figures on the screen is that they are not colossi - they do not stand in relation to smaller figures to remind us of our triviality. Nor are they the giants of novels, wonderful in their stature. Their scale is unique - both realistic and fantastic.

What's actually magnified, you realise, is not so much the objects on screen but our capacity to see them, Scorsese knows this simple thrill well - The Color of Money, not an entirely successful film, is none the less memorable for two or three stunningly beautiful close-ups. One in particular also employs slow-motion (a temporal close-up which is also a particular privilege of cinema; sculpture can do freeze-frames, as Bernini's Apollo and Daphne proves, but only film can make movement obedient to our attention). The image is of a pool ball struck by the tip of a cue, the instant of impact registered with an explosion of blue chalk dust. A Jean Luc Godard movie, I forget which, offers a similar close-up, this time of the tip of a lit cigarette as someone draws on the filter. And what you think is not "God, what a vast cigarette" but "God, how beautiful a cigarette looks - how marvellous the way that flameless fire crinkles through the tobacco". Television and the diminished screens of the multiplex can offer a shrunken version of this pleasure, but not the awe of looking up to the image. It reminds you that a spectacle, as the dictionary confirms, is not just something to look at but something that helps you see.