The Collaborative International Dictionary of English v.0.48:

Crucible \Cru"ci*ble\ (kr[udd]"s[i^]*b'l), n. [LL. crucibulum a
   hanging lamp, an earthen pot for melting metals (cf. OF.
   croisel, creuseul, sort of lamp, crucible, F. creuset
   crucible), prob. of German origin; cf. OHG. kr[=u]sul, LG.
   kr["u]sel, hanging lamp, kroos, kruus, mug, jug, jar, D.
   kroes cup, crucible, Dan. kruus, Sw. krus, E. cruse. It was
   confused with derivatives of L. crux cross (cf. Crosslet),
   and crucibles were said to have been marked with a cross, to
   prevent the devil from marring the chemical operation. See
   Cruse, and cf. Cresset.]
   1. A vessel or melting pot, composed of some very refractory
      substance, as clay, graphite, platinum, and used for
      melting and calcining substances which require a strong
      degree of heat, as metals, ores, etc.
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   2. A hollow place at the bottom of a furnace, to receive the
      melted metal.
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   3. A test of the most decisive kind; a severe trial; as, the
      crucible of affliction.
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   Hessian crucible (Chem.), a cheap, brittle, and fragile,
      but very refractory crucible, composed of the finest fire
      clay and sand, and commonly used for a single heating; --
      named from the place of manufacture.
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The Collaborative International Dictionary of English v.0.48:

Hessian \Hes"sian\, a.
   Of or relating to Hesse, in Germany, or to the Hessians.
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   Hessian boots, or Hessians, boot of a kind worn in
      England, in the early part of the nineteenth century,
      tasseled in front. --Thackeray.

   Hessian cloth, or Hessians, a coarse hempen cloth for
      sacking.

   Hessian crucible. See under Crucible.

   Hessian fly (Zool.), a small dipterous fly or midge
      (Cecidomyia destructor). Its larv[ae] live between the
      base of the lower leaves and the stalk of wheat, and are
      very destructive to young wheat; -- so called from the
      erroneous idea that it was brought into America by the
      Hessian troops, during the Revolution.
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