Source : Webster's Revised Unabridged Dictionary (1913)

Investigable \In*ves"ti*ga*ble\, a. [L. investigabilis. See
   {Investigate}.]
   Capable or susceptible of being investigated; admitting
   research. --Hooker.

Investigable \In*ves"ti*ga*ble\, a. [L. investigabilis. See
   {In-} not, and {Vestigate}.]
   Unsearchable; inscrutable. [Obs.]

         So unsearchable the judgment and so investigable the
         ways thereof.                            --Bale.