Yep -- Humphry Davy died inhaling oxides of nitrogen. Turned
out they weren't all as much fun as nitrous oxide.

Even the technique we learned in high school, of wafting vapors
toward the nose with the hand, is considered incredibly stupid
these days.

Martin H. Eastburn wrote:
In the late 1800 and early 1900's a lot of really good Physicists and
Chemists
died due to carelessness or lack of knowledge at the time.