Pay a stranger's way

This happened on Saturday 10th June. I decided to send it as a good news story to the local paper. They printed it.

I happened upon a car boot sale as I was walking to the hairdresser. I came across a teapot with a strainer built in for your tea leaves. I'd been looking for one as I've decided to use loose tea in a small effort to reduce plastic - tea bags have plastic in them and indeed a second hand teapot to reduce waste.

When I came to buy I realised I had no cash. A kind lady paid the £1 for me. As a result I said I'd buy someone a drink when I got to town; which I did. He looked somewhat bemussed until I explained. I then suggested he did an act of kindness for someone else. Did the chain reaction end there? Perhaps someone out there knows the answer.