The other day, friend Mark was telling me I ooze 'Don't come and sit next to me and definitely don't talk to me' vibes.

Tried to tell him this may be because I am visually impaired and have to frown slightly in order to focus properly; but he says it's because I actually don't want anyone to come and sit next to me or talk to me.

Which is true - apart from blond athletic man from Hassocks of course, who is more than welcome to sit next to me and talk to me until the cows come home but never actually exchanges more than the odd jokey remark (and I'm usually the brunt of the jokey bit).

However, determined to prove to Mark that I was in fact a charming, friendly person with an open and inviting demeanour, I made the mistake of smiling at a four-year-old boy and his mother, who were travelling up to London on the 8.18.

They'd made the mistake of thinking they would have no problem sitting together, but by the time they boarded the train most of the seats were taken, apart from two, one next to self and one next to the man sitting opposite self.

Being a charming and friendly person with an open and inviting demeanour, I followed up my winning smile at them with an offer to move and sit next to man opposite self, thus allowing them to sit next to each other.

But - eat your words Mark - the four-year-old had by this time taken a shine to self and said he wanted to sit next to me.

I smiled again, before giving him a warning frown which clearly said: "Don't talk to me. I've got a full day's work ahead of me and can't be doing with talking to people in whom I have no vested interest all the way to London."

But boy obviously mistook the look for a further open, friendly glance and a definite invitation to chat.

"Want to see my cow?" he threatened, rather than asked.

"That would be lovely..." I replied, scowling.

Boy then produced a stuffed black and white cow with a unique stuffed toy party piece.

"It's mad..." he informed, pressing a button on the cow's felt hoof. The cow then proceeded to moo, slowly at first, and then more quickly. "Moo (pause), moo (pause), moo (pause), moo, moo, moo...", and then, just when I thought it would stop, it began to vibrate and laugh and moo all at the same time. "Moo, ha ha ha! Moo, moo ha ha ha! Moo Moooo! Ha ha ha!", went the cow.

"Ha ha, very funny," said I, looking to the mother to exert a bit of discipline and tell him to shut the bloody cow up. She merely smiled at me, what with me being the open inviting person that I am, and told me that the cow was a gift from a relative in America.

So that was it for the rest of journey. I smiled, the mad cow mooed and vibrated until we reached Victoria when I made dash for freedom.

The trouble was that, like some irritating Spice Girls' number, the vaguely rhythmic mooing and laughing of the cow managed to lodge its vague rhythm into my brain.

So I found myself humming; "Moo, moo, ha ha ha!" under my breath at various times during the day.

The last of which was when I was on my way home and blond athletic man from Hassocks happened to be sitting next to me.

So I happened to find myself stifling the last of the vaguely audible moos that I was humming, in order to smile at him in an inviting and friendly way.

He merely opened a newspaper and stuck his nose in it - in such a way as to indicate that he was not in talking mood.

Though I, as I've already mentioned, would have been happy to talk to him until the cows . . .