_Mineral Acids._--As it is generally supposed that these powerful solvents
were not known anterior to circiter A.D. 1100, I should be glad to learn
what opinion is entertained by the learned concerning {340} the death of
the prophet Haken al Mokannah. This person is said to have disappeared in
785, or 163 of the Hejrah, by casting himself into a barrel of corrosive
fluids, which dissolved his body. Is it not the best supposition, that this
story was supposed by Khondemir and others, in more advanced ages of
science, to account for the fact of his having disappeared, and of his real
fate having never been ascertained? I have never seen this apparent
anticipation of chemical discoveries animadverted on.