The dropped toast debate

This Is the weightiest subject ever covered by a 10oz paperback : gravity. Fortunately Joseph Lanza ain't heavy - he's an author. He throws his material skywards - bungee jumping, sagging boobs, Big Dippers, weightlessness in space and buttered toast - and it freefalls into agreeable patterns on the page.

Lifts come into it too, as a natural progression from his recent book on elevator Muzak. Staircases as well; there has been research, unsuccessful so far, to make ascent easy by covering the bottom step with an "anti- gravity" layer.

Lanza offers a lucky dip and a cultural tour. His favourite theme is the roller-coaster and he certainly put in the hours of research, including one ride during which the stranger sitting next to him released their safety bar to boost the thrill. He includes a photograph of "holy rollers", the real-life equivalent of Peter Cook's Leaping Nuns: a plunging roller- coaster crammed with black-garbed Sisters on their works outing to an amusement park.

He gives us a crash course in films that rely on the power of gravity. The most famous shot is probably that of the pram tumbling down the steps in Battleship Potemkin; the least known is The White Hell of Pitz Palu, a mountain movie in which an explosion actually sent an avalanche over its star, Leni Riefenstahl, who went on as a director to give us those shots of Hitler's plane casting its shadow over massed troops marching through the streets of Nuremburg.

Although the Germans plunged ahead in the cinematic gravity stakes, Lanza reckons that the first aircraft disaster movie was The High and The Mighty with John Wayne in 1954. The Americans also cornered the market in movies based on buildings from the tops of which it is a long way to fall. The Towering Inferno springs to mind - unfortunately - but Hitchcock's Vertigo is a more classy example.

Occasionally Lanza ought to keep his feet more firmly on the ground. There is far too much about that sequinned pianist Liberace, who is included not because the glittering fraud used to "fly" on stage like a gone-to- seed Peter Pan but because he was a light-weight cultural icon. That is a section which should have been shot down in flames, as should the passage on "angel food", introduced because it is a fluffy item of patisserie.

However anarchic, a book which is entitled Gravity really ought to have more science in it than this one. Lanza gives us only the odd mention of black holes, those ultimate forms of gravitational excess in which light itself is pulled back into a whirlpool of weight. Surely he could have explained, even at a basic level intelligible to a Flat Earther like myself, something of the power that keeps the galaxies flying in formation. And there is only the briefest mention of the Big Crunch in which gravity may have the last laugh by pulling us all back into the Big Bang state where our atoms began.

Newton's apple deservedly gets an early mention (although Michael White's new biography suggests that it was an afterthought, not Sir Isaac's original inspiration). But what about the previous theories of how the whole cosmic shebang held together, before Newton put us straight? I would also have liked something about the far-out theory that a rogue planet swept lethally close to Earth, a scenario which would make a great disaster movie.

Still, credit where credit is due. There is a marvellous photograph of a spot in California - it would be California, wouldn't it? - where, thanks to offbeat gravity, people who attempt to stand upright are pulled several degrees from the vertical. Also provided is full coverage of the state of play on the dropped toast debate.

Sod's law says it falls butter-side down. And so does a recent experiment. This is nothing to do with the butter itself but relates to the fact that, falling from the top of a table to the floor, the toast only has time to flip through 180 degrees. If tables were twice as high, toast would twist through the full 360 degrees and land butter-side upwards. But then we would have to grow twice as tall, which we can't. Too much gravity, apparently.