
    (No. 6050
    Minnesota Mining and Manufacturing Company, Claimant, vs. State of Illinois, Department of Public Works and Buildings, Respondent.
    
      Opinion filed August 30, 1971.
    
    Charles W. Ott, Attorney for Claimant.
    William J. Scott, Attorney General; Saul R. Wexler, Assistant Attorney General, for Respondent.
   Perlin, C.J.  