My poor heart’s turned into a little rib-caged bird, there’s something exhilarating about finding the baby – like spotting fish in rivers (or foxes in fields or deer in woods) but at the same time finding the baby is terrifying (tigers in trees, snakes in the grass). And the baby isn’t just a mysterious mis-delivery by the baby shop, it brings with it myth and legend – Moses and Oedipus and the fairy’s changeling.

Gingerly, I pick up the whole box, I don’t really want to handle the baby in case I damage it (or vice versa).

‘Look,’ I say to Vinny, holding out the cardboard box for her inspection.

‘Whatever it is, we don’t want any of it,’ she says, pushing it away.

‘No, look,’ I insist. She lifts one of the flaps of the box and her mouth falls open in disbelief. ‘What is it?’

‘What does it look like?’

Vinny shrinks away from the cardboard box in the same way other people shrink from rodents. ‘A baby?’

‘Yes.’

She shakes her head in bafflement. ‘But why?’ But this is not the time for existential questions, the baby has opened its new eyes and started to bawl. ‘Take it away,’ Vinny says quickly. I place the box on the floor between us so that we can get used to it slowly.

Charles comes back with the Dog and we show him the baby, which has given up crying and gone back to sleep. The Dog sticks its head inside the box and wags its tail enthusiastically but then, unfortunately, starts to lick the baby and it wakes up and starts bawling again. Maybe the Dog can look after it, ‘Like Romulus and Remus?’ Charles says. ‘Or Peter Pan.’ (He knows, he is a Lost Boy himself.) The baby’s crying has reached a critical level but unfortunately the Dog is the wrong sex to succour it.

Charles lifts the baby out of the box as if it’s an unexploded bomb and holds it out from his body with his arms stiff so that the baby, thinking it’s about to be dropped from a great height, starts to scream horribly. Vinny has a tentative go, jiggling it around in a self-conscious way, with a rictus of a smile on her face, but, as you might expect, this only makes matters worse. Luckily, just then Debbie and Gordon come home and although there are a few minutes of complete disbelief, followed by hysteria and ending in furious discussion, the end result is that Debbie ‘will keep the kid’.

‘You can’t keep it,’ Gordon says, horrified.

‘Why not?’

‘Because you just can’t. It’s not yours.’ Debbie waves the ruled paper around under Gordon’s nose. ‘What does that say, Gordon?’

‘I know what it says, Debs,’ he says gently, ‘but we have to take the baby to the police.’

‘And what will they do with it? Put it in an orphanage that’s what. Or,’ she adds balefully, ‘a prison cell. Nobody wants this baby, Gordon, and somebody has asked us to look after it. “Please look after me”, it says so right here.’

‘And what are you going to tell people?’ Gordon asks incredulously.

‘I’ll just say it’s mine.’

‘Yours?’ Gordon asks.

‘Yes, I’ll say it was a home delivery [which I suppose is true]. Nobody will know.’ Debbie is fat enough to have had a baby without anybody knowing and you do hear about people giving birth without expecting to – standing at the cooker heating milk one minute, the next – a parent. ‘People believe anything you tell them,’ Debbie says. ‘And we’ll just say, “We’ve been so disappointed in the past that we didn’t want to talk about it too much and spoil our luck.” And look how lucky we are,’ she adds, and starts to make baby talk to the baby that’s such drivel that it drives Vinny from the room. The baby looks as though given half a chance it would be off as well. ‘People don’t care, Gordon,’ Debbie says crossly when he starts objecting again, ‘nobody cares what anybody does, not really. You can get away with murder and nobody would notice.’ Gordon flinches and stares at the baby.

I suppose, in a way, it is like murder – for every one murder that’s discovered there are probably twenty that pass unremarked. The same is probably true of babies, for every one you hear about that’s been abandoned on a doorstep there are probably twenty taken in with the milk.

‘He’s hungry, poor chap,’ Gordon says, visibly softening.

‘It’s a her, silly,’ Debbie says (in her element now), unwrapping her baby gift to show Gordon, for the baby did not come naked to the doorstep of Arden, it came carefully gift-wrapped in a shawl as white as snow and as full of cockleshells as the sea.

Everything dies, but gets transformed into something else – dust, ash, humus, food for the worms. Nothing ever truly ceases to exist, it just becomes something else, so it can’t be lost for ever. Everything that dies comes back one way or another. And maybe people just come back as new people – maybe the baby’s the reincarnation of someone else?

The molecules of one thing split apart and team up with different molecules and become something else. There’s no such thing as nothing, after all – unless it’s the great void of space – and perhaps even there are more things than are dreamt of in our philosophy. (Just because you can’t see something doesn’t mean it doesn’t exist.)

Perhaps there are molecules of time that we don’t know about yet – invisible, rarefied molecules that look nothing like ping-pong balls – and perhaps the molecules of time can rearrange themselves and send you flying off in any direction, past, future, maybe even a parallel present.

Eunice is waiting for me at the corner of the street, looking pointedly at her watch – the usual dumbshow of punctual people who want to display their moral superiority to their unpunctual friends (how much easier if the punctual people just turned up late). The clocks have recently changed, a day late in our inefficient household where we never know whether time is going forwards or backwards. ‘Spring forward, fall back,’ Eunice chants. ‘Daylight saving’ – what an amazing idea. (If only you could, but where would you keep it? With the time that’s found? Or the time that’s kept? A treasure chest, or a hole in the ground?)

‘You’re late,’ Eunice says.

‘Better than never,’ I reply irritably. Audrey’s already waiting at the bus-stop. ‘Look,’ I say to her as I spot a red squirrel helter-skeltering around one of the solid sycamores and Eunice is prompted to explain to us in great detail why this is impossible as there are no red squirrels in Glebelands. (Perhaps it’s Ratatosk who runs up and down the great ash Ysggadril?)

Eunice launches into a lecture about the differences between red and grey squirrels when Audrey absent-mindedly ventures, ‘Not just the difference between red and grey then?’

I watch a red-gold leaf drift down and catch on Audrey’s hair. It gives me a funny feeling in the pit of my stomach. I have to say something to Audrey. I have to say something about the baby, about the cockleshell shawl which Debbie handed swiftly over to our waste disposal unit (Vinny), to be burnt on a bonfire and which my memory now questions ever having seen. (‘What happened to that lovely shawl you were knitting for your niece in South Africa?’ I ask Mrs Baxter casually. ‘Oh, I finished it,’ she says, pleased at the memory, ‘and sent it off in the post.’ So there you go.)

‘Here’s the bus,’ Eunice announces as if we can’t see for ourselves the red double-decker steaming up Sycamore Street towards our bus-stop, its final outpost before it turns around and heads back into town.

And then I watch it disappear before my eyes.

‘Hang on a minute,’ I say, turning to Audrey in amazement to see if she’s witnessed this extraordinary vanishing act but, lo and behold, she’s gone too. And Eunice. And the bus-stop and the pavements, houses, trees, aerials, rooftops … the past has come crashing through into the present again without a by-your-leave.

I’m standing in the middle of an impenetrable thicket of Scots pine, birch and aspen, of English elm and wych elm, common hazel, oak and holly, stranded in the middle of a great green ocean. It might not be the past, of course – instead of time-travelling I might simply have travelled – been picked up by some giant, invisible hand and deposited down again in the middle of a great wildwood. But it feels like the past, it feels as if the clocks have gone right back to the beginning of time, the time when there was still magic locked in the land. On the other hand, I can’t have gone back much more than twelve million years, give or take a second or two, if Miss Thompsett’s history of photosynthesis is correct. (Most of the trees we know today were in existence by twelve million years ago.)

I pick up a leaf skeleton. It is autumn in the past too. The mouldering mushroom smell of decay is in my nostrils. A dark blanket of green ivy covers the ground. It is incredibly quiet, the only sound is birdsong. Even the sweet birds singing hidden in the trees only contribute to the peace in their great forest cathedral. Perhaps I’m not at the beginning of time, but at the end, when all the people have gone and the forest has reclaimed the earth.

I like it here, it’s more restful than the present, wherever that is. I shall gather nuts and berries and make myself a nest in the hollow of a tree and become as nimble as a squirrel in my great sylvan home. Does this forest have an end, does it have distinct boundaries where the trees stop, or does it go on for ever, curling like a leafy shawl around the earth, making an infinity of the great globe?

But then, sadly, I am ripped out of my new Eden by the number 21 bus smashing through the wildwood in a great cracking and splintering of branches, sending leaves flying up in the air. The bus rolls towards me and stops. The ancient wood has vanished. I am back at the bus-stop.

‘Izzie?’ Audrey says, stepping on to the platform of the bus. ‘Come on.’ I climb on board and listen to the conductor ringing the bell and the engine revving noisily and proffer my fare with a sigh. How phlegmatic I am in the face of unravelling time.

I look at Audrey sitting next to me, reading over her French grammar, and say nothing. We all have our own secrets to keep, I suppose.

Why am I dropping into random pockets of time and then popping back out again? Am I really doing it or am I imagining I’m doing it? Is this some kind of episte-mological ordeal I’ve been set? I should never have tried to kill time. I wasted it and now it’s wasting me.

If I had more control it might be useful – I could go back and put all my money on the three o’clock winner at Sandown or patent the electric lightbulb, or any one of the usual fantasies of would-be time-travellers. Or – more thrilling – I could go back and meet my mother. (‘You could meet her now if you had her address,’ Debbie says, rather sarcastically.) I finger the leaf skeleton in my hand – it wouldn’t really stand up as evidence in court, it looks exactly like one I could have picked up a minute ago on the streets of trees.

Carmen is deep in preparation for her marriage to Bash. ‘You don’t think you should wait a bit?’ I ask doubtfully.

‘Oh come on – I’m sixteen, I’m not a child,’ Carmen says, pushing a huge gobstopper from one side of her mouth to the other. When will I find someone who thinks enough about me to take me to the Gaumont on King Street, let alone marry me? ‘Oh, it’ll happen to you one day,’ Carmen says airily. ‘It happens to everyone – you fall in love, you get married, you have kids, that’s what you do … someone will come along.’

(‘Oh, one day,’ Mrs Baxter says, equally assured, ‘your prince will come [she almost breaks into song] and you’ll fall in love and be happy.’ But what if the prince that came looked like Mr Baxter, all rusty armour and gimlet visor?)

But no-one will ever want me once they find out how mad I am. And anyway I don’t want ‘someone’, I want Malcolm Lovat.

How shall I kill Hilary? Fly agaric? Aconite slipped from a ring on my finger? Bash her skull in like a boiled egg or a beechnut? Or better still take her with me when I next fly through time and dump her in the pre-shampoo past, twelfth-century Mongolia say. That would teach her.

‘What do boys see in Hilary?’ Eunice says dismissively. ‘So OK – she’s got long blond hair and big blue eyes and a perfect figure – but what else has she got going for her?’ (Eunice is annoyed with Hilary because she’s beaten her in a chemistry test.)

‘Hmm? What else?’ Carmen explains patiently to her that that’s enough for most boys. She fishes in her handbag for a packet of ten Player’s No 6 and shakes out cigarettes on my bed. ‘Go on,’ she urges Eunice, ‘it won’t kill you.’

We suck on cigarettes. Carmen also manages to stuff in a mint, elliptical rather than round (perhaps if her mouth stopped working for more than a minute she would die). Audrey is, as usual, absent. ‘What’s wrong with Audrey?’ Carmen asks.

‘She’s got flu again.’

‘No, I mean what’s wrong with her?’ Somewhere in the depths of the house the baby cries. ‘How’s she getting on?’ Carmen asks, cocking her head in the direction of what I suppose she intends to be Debbie.

‘Well … it’s hard to explain exactly. She’s kind of loopy.’

‘That happened to my mother after she had every one of us,’ Carmen says, ‘it goes away. Women’s trouble,’ she adds with a knowing sigh. I don’t think Debbie’s loopiness is going to go away, the baby is now the only person in her immediate family whom she doesn’t think has been replaced by an accurate replica of themselves. The baby’s squalls grow louder (in some ways it reminds me of Vinny) and all of a sudden the scent of sadness passes me by like a cold draught of air and I shiver.

‘Someone walk over your grave?’ Carmen says sympathetically.

‘That’s a ridiculous saying,’ Eunice says (Eunice would be happier if words could be replaced by chemical formulas and algebraic equations). ‘You’d have to be dead in order to be in your grave, but you’re sitting here alive in the present.’

‘The living dead,’ Carmen says cheerfully, stuffing lemon bon-bons into her mouth. Maybe we’re all the living dead, reconstituted from the dust of the dead, like mud pies. The cries of the baby upsets my invisible ghost, making it waver and shimmer on the spiritual wavelength like an invisible aurora borealis. ‘What’s that funny smell?’ (Spirit of health? Or goblin damned?) Carmen asks, sniffing the air suspiciously.

‘Just my ghost.’

‘Ghosts,’ Eunice scoffs, ‘there’s no such thing, it’s a completely irrational fear. Phasmophobia.’

But I’m not afraid of my ghost. He – or she – is like an old friend, a comfortable shoe. Phasmophilia.

‘That sounds perfectly disgusting,’ Eunice says, making a face which does nothing for her.

I have to translate Ovid. In Metamorphoses you can’t move for people turning into swans, heifers, bears, newts, spiders, bats, birds, stars, partridges and water, lots of water. That’s the trouble with having god-like powers, it’s too tempting to use them. If I had meta-morphic powers I’d be employing them at every opportunity – Debbie would have been turned into an ass long ago, and Hilary would be hopping about as a frog.

And me, I am a daughter of the sun, turned by grief into something strange. For homework, I’m translating the story of Phaeton’s sisters, a story of nature green in bud and leaf. Phaeton’s sisters who mourned so much for their charred brother that they turned into trees – imagine their feelings as they found their feet were fast to the earth, turning, even as they looked, into roots. When they tore their hair they found their hands were full, not of hair, but of leaves. Their legs were trapped inside tree-trunks, their arms formed branches and they watched in horror as bark crept over their breasts and stomachs. Clymene, their poor mother, frantically trying to pull the bark off her daughters, instead snapped their fragile branches and her tree-daughters cried out to her in pain and terror, begging her not to hurt them any more.

Then slowly, slowly, the bark crept over their faces, until only their mouths remained and their mother rushed from one to another, kissing her daughters in a frenzy. Then, at last, they bid their mother one last terrible farewell before the bark closed over their lips for ever. They continued to weep even when turned into trees, their tears dropping into the river flowing at their feet and forming drops of sun-coloured amber.

(‘Rather an emotional translation, Isobel,’ is my Latin teacher’s usual verdict.) Only the lonely know how I feel.

Will I ever be happy? Probably not. Will I ever kiss Malcolm Lovat? Probably not. I know this catechism, it leads to the slough of despond and a sleepless night.

Where is Malcolm? Why isn’t he knocking at my window instead of the cold, hard rain? Where is my mother?

I fall asleep with the smell of woodsmoke in my hair and the scent of sadness coiled around me like a vine, and dream that I’m lost in an endless dark wood, alone and with no rescuer, not even Virgil come to offer me a package holiday to hell as my forfeit.