I've never been much interested in science fiction. I'm particularly bored by writers telling of the invasion of Planet Earth by belligerent aliens who swoop down on us in krypton-powered flying-saucers and zap us with ray guns. Invasions are so old hat! If you want to know where the next real threat to our earthling civilisation is coming from, you need look no further than the street where you live. Sidling up alley ways, lurking on rooftops, crouched behind shed doors, the enemy are without. They may even be within. Lying on your sofa, hogging your hearthrug, clawing your lap, miaowing for prime steak and salmon; or simply purring. Don't be fooled. Cats are the enemy, the next threat. In the words of someone whose name escapes me (but it may well have been Old Possum himself): "Cats are watching, and waiting to take over the world."

Please understand that I'm not anti-cat. I'm very pro-cat. I like pets that bury their faeces. I think that's so neat! I like dogs too. But dogs aren't a threat to civilisation. Can you imagine dogs trying to take over the world? All that anxious tail-wagging, pleading eye-contact and sloppy licking! You'd just have to tell the dog soldiers "Sit!" then "Go fetch!" and the uprising would be over in a jiffy.

Cats on the other hand, are subtle, devious and self-serving. That's why we love them. "To his dog," wrote Aldous Huxley, "every man is Napoleon; hence the constant popularity of dogs." Contrast this with Montaigne:"When I play with my cat, who knows if she is not amusing herself with me more than I am with her?" As it happens, I do. She is. She is doing just what cats do; which is suiting herself and biding her time until word comes from cat HQ that the time is ripe. When it does, and cats finally turn on humankind, Daphne du Maurier's story The Birds will look very tame indeed. But we cat people don't worry too much about about the cataclysm. We reckon that we'll be looked after all right by our new feline masters. It's only those people who kick cats, and put them in microwave ovens, and tie their tails together (please children do not try any of these things) who will be subjected to everlasting torment and a good thing too. However, just to make absolutely sure I get fair treatment, I want to put on official record the reasons why, finally, my bookshop has become catless.

Miss Black, my friend and familiar of nearly ten years, has found a new home and (I hope) a better life with a nice family in North Melbourne. For the past two years she has attempted to adapt to life as a bookshop cat. Without much success. It has not been easy for her, or me. Perhaps if we'd both been younger, less set in our ways...who knows? I have encountered numerous cats in bookshops which have seemed to me to be the Perfect Form of bookshop cat-ness. Fat, comfortable, torpid creatures draped over bookshelves, curled up on armchairs, purring and compliant, they have seemed to fit perfectly the comfortable ambience around them. They have never appeared to be stressed or aggressive or even hungry. Maybe this contented languor is the product of idyllic kittenhood. Miss Black's kittenhood may well have been idyllic, or horrific, I don't know. She was already full-grown, a year old at least, when she chose me for her companion and provider, as I visited the pound of the Cat Protection Society in Greensborough. I thought I was looking for a small tabby male kitten to take home with me, but I must have been mistaken. Sitting on a tree stump somewhat aloof from the other cats, Miss Black blinked her yellow eyes at me, chirped a small greeting and offered me an elegant black paw. I was hooked.

Since then, we've been through a fair bit. Upheavals of all sorts: divorce, dislocations, dogs, to name a few. But she's a survivor. What she couldn't take happily was relocation to an inner urban flat. She needed territory, the vet said. She was accustomed to a yard or a garden, which she patrolled and protected against all comers. Suddenly she had nothing, except a rooftop and a lane infested with twenty or more street-smart competitor cats. She sulked and got stressed. Her sleek black coat became dull and moth-eaten; she turned into a pathological washer and groomer, forever licking and worrying herself, until raw sores broke out on her back. "Feline Stress Syndrome," said the vet. We tried cat vallium and hormone treatment and fresh rabbit but all this was treating the symptoms not the cause. She would get better for a while then her troubles would start again. After two years of trying to cope, I put a notice in the window. "Wanted: a home for Miss Black." Two weeks ago she moved out. I have my fingers crossed that she's happily settled where she is.

I'm not surprised how much I miss her. Bernard does too. And many of our customers seem to be genuinely concerned by her disappearance. "Where's the cat?" they say. "We love seeing her as we go past. Your windows aren't the same without her." No, they're not. For one thing, the books on display don't get stirred around by pussy paws any more, or shouldered into disarray as Miss, ignoring her basket, makes herself comfortable in a patch of sunlight. No longer are books in the window lightly veiled with a top-dressing of black hairs which Miss Black has scratched or licked or vomited over them. Ah me, where are the furballs of yesteryear? Safe and well in North Melbourne I hope.

With Miss Black's departure from the windows, peace comes too. It's a funny thing but if you have a cat in your shop window, passers-by regularly stop and exclaim:"Hey, look there's a cat in this window." Hundreds and hundreds of people make this acute observation every month. While it's perfectly comprehensible that they should do this, it's quite a bore when you have to listen to it week in week out. And the recurring wittiness of "How much for the cat in the window?" wears a little thin by the hundredth time you've heard it. I rather relish the much less common "Ooh crikey, it's a black cat, that'll ruin my day." But not many people seem to be superstitious about black cats nowadays.

Best of all, the window-tapping has ceased. Every day someone stopping to admire Miss Black would tap on the plate glass, with a fingernail, or a coin or a key, to attract her attention. Tap-tap-tap. TAP-TAP-TAP. If asleep, she would wake with a start, blinking and twitching. On bad days, this might happen three times or more. "There you are, you're a very nice pussy cat, aren't you?" the perpetrator would say. "And you're a nitwit," I would mutter (occasionally substituting a stronger substantive). What is it that impels apparently quite normal people to indulge in this sort of cat-baiting? Is it a cry for help, a plea to be noticed? On some days, Miss Black decided she had had enough of her public; she would withdraw from the window completely. And once or twice I had enough too. "Stop tapping on the window, can't you? Just go away and leave the bloody cat alone!" I was pleased when these outbursts gave the startled tappers a taste of their own medicine. Men as well as cats have their breaking point.

Miss Black, I should add, was by no means always on the defensive. She launched regular attacks on Sultan, the Alaskan Malamut, who passed the shop at least twice a day. She disliked all dogs on principle, but for Sultan she reserved a special spiteful loathing. Whenever he ambled past with his handler, she flew at him, spitting like a firecracker, and braked hard only at the last moment to avoid contact. If glass door or window intervened, she hurled herself at it with shrieks of frustration. "You'll be glad to hear that my cat's gone," I said to Sultan's amiable owner. "I shall miss her," she said."I trained him not to eat cats, and it was good to have so many chances to reinforce the lesson." I almost think that Sultan misses his daily assaults. He deserves a medal for valor and self-control in the face of considerable provocation. She would have made a tasty snack for a big husky.

Nor were children entirely safe with her. Mostly she would tolerate them, but small people who grabbed at her or chased her or tried to pick her up got short shrift. A quick swipe of claw across knuckles usually sufficed to let them know her feelings. Once she bit a small, and rather sweet, girl on the cheek simply because she'd had enough of being fussed over for one day. After this happened I would issue warnings to children (and their parents). "The cat is not a toy. She may scratch or bite without warning. So be careful." Maybe I should have posted a notice inside the shop to this effect. It occurs to me that I could have been sued by the parents of children bitten or scratched by my cat. Law suits, claims for damages? Would my public liability insurance cover me for this? Luckily most people seem to accept that cats are unpredictable. Especially if they are black, with wild yellow eyes. The cats, I mean.

If you have read this far and you are not a cat-enthusiast, congratulations. You show an admirable largeness of spirit. But I suspect that in book-land you are heavily out-numbered. Cats and books go together; book-people are very often cat-people. If you need confirmation of this, browse through Christabel Aberconway's A Dictionary of Cat Lovers (MIchael Joseph 1949) or Suares and Schwartz's The Literary Cat"(Pushpin Press 1977), both informative and entertaining books. Consider too that the cat is emblematic of introversion and peaceful introspection (as the dog is its opposite); so it comes as no great surprise that cat-lovers like to lose themselves in the solitary (and mildly suspect) pursuits of reading and writing books. It may also be true that cat people, being reflective and articulate, make more noise in print than their numbers really warrant.

I was taken aback to read this entry under "Dogs" in an edition of Waterstone's Guide to Books (1987): "Dogs are even better catered for than cats in print; not just because they are more interesting and useful, but also because they need more looking after than the self-sufficient feline." More interesting? More useful? Better catered for? I looked at the dreary list of "How to Look After Your Rottweiler" type of books, and I thought this was a classic case of confusing quantity with quality. I like dogs all right, but by and large I'm not much impressed with dog books. As a boy I enjoyed Thy Servant a Dog by Kipling. I thought I'd follow this up with The Maltese Cat by the same author. It was a surprise. It has nothing to do with cats at all. Or Malta. It's about a polo pony in India. A useful point for secondhand booksellers!

I have dwelt on the negatives of Miss Black's reign. But set down this, too. She kept mice and rats away. She shredded cardboard cartons, but never sharpened her claws on the spines or covers of books. And when she hopped on to my knee on quiet afternoons, or sat on the desk purring quietly, or lay curled up in her basket, she was an ideal companion. On her good days, we could both relax. She liked to be admired and talked about by the many cat-lovers who come to the shop. And though she was difficult at times, she was the heart-beat of the shop. She welcomed me each morning with her little chirp of greeting, and at six o'clock sharp she reminded me that it was her tea-time, time to close up . I miss her, but I'm glad that she's settled in a better environment.

So there it is. This is my apologia. I am slowly recovering from my Feline Stress Syndrome. I hope this statement will be tendered as evidence on my behalf when, as it will, the pussy putsch finally happens.