Dear Edinburgh, women need more public toilets. And that doesn't make us 'funny wee things'! – Susan Morrison

You will have seen these women. You might be one of them. They scythe through crowds like heat-seeking missiles. The high-speed walk is insanely controlled. The eyes are gimlets. The expression is set to grim.

A West Highland Terrier, aka a 'funny wee thing', is not to be confused with Susan Morrison (Picture: Brad Barket/Getty Images)

Do not attempt to engage these women in conversation. It will not end well. I once saw a young scent-sniper leap out at a woman powering to the ladies room in John Lewis. Woman on a mission didn’t even slow. Eau de cologne all over the shop. Child was dang near blinded by Parfum de Costlee Summer Edition.

This woman needs to get to the toilet. Stat.

There are a lot of women out here who need those loos. I’m one of them. Two children, gravity, age and Mother Nature gave the advantage of a far more accessible wastewater disposal system to the men. So much for sisterhood.

We tend to be on the lookout for the loo. Unfamiliar surroundings must be visually mapped, like the Terminator scoping for Sarah Connor. You might see a perfectly calm exterior, but those eyes are sweeping the room until the target is acquired, distance assessed and bladder readiness ascertained. Then we can relax.

Out on the street, well, Princes Street to be precise, things have become ropier in the past few years. Reliable ports of call such as Debenhams (top floor, opposite the lifts), House of Fraser (second floor, easy to miss, but very nice) and BHS (basement) have gone.

West of John Lewis is a desert until you hit the little public loos in Princes Street Gardens (watch that one, make sure you get the right entrance. To the loo, that is, although that is generally good advice for women).

And no, it doesn’t matter if we have gone before we left the house. Mother Nature can play nasty tricks. One minute you’re driving beside the Forth on a gloriously sunny morning to Polmont Station to collect some friends, not a care in the world, and then bam! The Tinkle Bell goes off from the Bladder Department.

Polmont Station is many things, but I’d never put it up there with the great destinations of the world, like the Pyramids, the Great Wall or Notre Dame but suddenly, to me, Polmont was the Louvre, but only if there was a loo.

There is. Marching swiftly and with purpose, I followed the sign in, passing the ticket desk, just as a lovely lady in a high-vis jacket opened the office door and called out in my direction "time for a pee-pee, then, ya funny wee thing?"

Perhaps a tad over-friendly, but she could have called me Liz Truss at that moment and I wouldn’t have cared.

"Jings! How did you know?" I said.

She hadn’t seen me. She was startled, I was startled, and then the wee Westie at her side barked. That was the funny wee thing.

The dog and I both had our longed-for comfort break, only mine was indoors, in the beautifully clean loo. Thank you, Polmont station.

Dear ScotRail, please don’t give the Westie gal grief about her station dog. It was such a lovely thing to see. And secondly, please keep your train stations staffed. It makes a difference. And thirdly, to the rest of the world, we need more loos. Please.