Ronsterm, have you been to Britain? If you have when was it, or...

Ronsterm, have you been to Britain? If you have when was it, or if several times when?
Many years ago when coal smoke was belching from thousands of chimneys, and I'm talking homes here, what there was, was a fog so thick it was called smog.
Go there now and no coal smoke coming out of chimneys and voila no more smog. If you ever smelt this smog it was vile, a friend of mine had asthma, he couldn't go out, even being indoors he wasn't completely bereft of it.
Being on a coal fired boiler ship wasn't that good either because the smoke could and did when the conditions allowed it would affect passengers.
Please think more.