The Iron Tree
Dissolve iron filings in aqua fortis, moderately concentrated, till
the acid is saturated; then add to it gradually, a solution of fixed
alkali, (commonly called oil of tartar per deliquum.) A strong
effervescence will ensue, and the iron, instead of falling to the
bottom of the vessel, will afterwards rise so as to cover the sides,
forming a multitude of ramifications heaped one upon the other, which
will sometimes pass over the edge of the vessel, and extend themselves
on the outside, with all the appearance of a plant.