It was a big mistake when an employee at Bloor West and Lansdowne Ave. incorrectly mixed hydrochloric acid and sulphuric acid together. It makes a nasty mist that is somewhat caustic. As a result, residents were sent scurrying for cover with watering eyes and fits of coughing. The danger is now over, police say, but for a while people were warned to stay indoors and a TTC bus was used as a refuge for people who were caught on the street.