Ambika P3 is a windowless, cavernous basement once used to test concrete for huge building projects – the Channel Tunnel among them – now ingeniously recycled as a kunsthalle gallery / performance space.  Thus it is strikingly appropriate for its current incarnation.

It’s an instinct of curators to put the pieces back together, to reintroduce works of art which time and market forces have scattered to the four winds. In recent memory, exhibitions have reunited in one space all of Monet’s haystacks, Cézanne’s card players and, in the case of the National Gallery’s momentous Leonardo show, both versions of The Virgin on the Rocks. A new exhibition opened this week in Florence which takes the business of synthesis to the next level.

"In the midst of life we are in death.” This is a line we may feel compelled to reverse as we encounter the first exhibits in the British Museum’s extraordinarily powerful exhibition, for this is a display vividly bringing the dead to life in the very midst of their extraordinary demise. But then, “ashes to ashes” conveys particular resonance, too, for we all know that Pompeii, a town situated in the Bay of Naples, and its lesser known, less populous neighbour Herculaneum, were both covered in a thick layer of ash when Mount Vesuvius erupted in AD79.

It’s not often that a performance’s technological properties leaves you simply slack-jawed. Robert Wilson’s very long Swedish-language version of Strindberg’s A Dream Play did – at the same venue, though this time in 2001 – when the surtitle machines broke down (the audience gave an audible gasp of horror and then settled to its collective fate), but that was for altogether different reasons. Compared to what Ryoji Ikeda and his team are capable of, even the beautiful crispness of Kraftwerk’s stage shows fade into the realm of the bland.

Rodin’s The Burghers of Calais have decamped from their usual perch next to the House of Lords to cosy up to the work of Henry Moore. They can be found at Moore’s home and studio at Perry Green in Hertfordshire, in a tellingly succinct anthology of the towering giants of modern European sculpture. At first glance Rodin’s extraordinary evocations of energy and sensuality, literally embodied in the models he studied so intensively, and Moore’s semi-abstracted helmet heads and upright motives, don’t have much in common.

You might phrase the question rhetorically: “just what do artists do all day?” Or you might ask it in the spirit of genuine enquiry: after all, to many, the artist is an exotic creature whose mystery is still to be fully penetrated. Either way, it’s pretty clear that though it may not be “a proper job”,  artworks don’t make themselves. 

How much more of a melancholy experience walking round this exhibition would have been if its subject hadn’t just sprung a new album on us that’s so suffused with energy and life. It’s meant that the exhibition's title - David Bowie Is – feels like a genuine statement of fact rather than just wishful thinking, at least in the literal sense.

Glam. Were you there? If so, what was it all about? You might come up with a list: Roxy Music, Ziggy Stardust, shiny flares, Sweet, shaggy hair, the ubiquitous platform boot, T-Rex, glittery eye-shadow, lip-gloss pouts (on men). It was the era of dressing up and gender-bending as fashion statement, though it’s also true that the glamour in Glam Rock was more glitter paste than gold. Some of it remains pretty cool, but unlike the Sixties you probably wouldn’t want to go back there, or at least for no longer than it takes to get round this exhibition, though Glam!