[1] : The Collaborative International Dictionary of English v.0.48

tales \ta"les\ t=a"l=ez, n. l., pl. of talis such
   persons. law
   a pl. persons added to a jury, commonly from those in or
       about the courthouse, to make up any deficiency in the
       number of jurors regularly summoned, being like, or such
       as, the latter. --blount. --blackstone.
   b syntactically sing. the writ by which such persons are
       summoned.
       1913 webster

   tales book, a book containing the names of such as are
      admitted of the tales. --blount. --craig.

   tales de circumstantibus l., such, or the like, from
      those standing about.
      1913 webster
see also:
tales book tales de circumstantibus 

[2] : Bouvier's Law Dictionary, Revised 6th Ed (1856)

tales de circumstantibus, practice. such persons as are standing round. when 
ever the panel of the jury is exhausted the court order that the jurors 
wanted shall be selected from among the bystanders which order bears the 
name of tales d circumstantibus. bac. ab. juries, c. 
     2. the judiciary act of sept. 24, 1789, 1 story, l. u. s. 64, provides, 
sec. 29, that when from challenges, or otherwise, there shall not be a jury 
to determine any civil or criminal cause, the marshal or his deputy shall, 
by order of the court where such defect of jurors shall happen, return 
jurymen de talibus circumstantibus sufficient to complete the panel; and 
when the marshal or his deputy are disqualified as aforesaid, jurors may be 
returned by such disinterested persons as the court shall appoint. see 2 
hill, so. car. r. 381; 2 penna. r. 412; 4 yeates, 236; coxe, 283; 1 blackf. 
63; 2 harr.  j. 426; 1 pick. 43, n. 

Tales >> T Words
Tales, definition of term: Tales
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