      SUBROUTINE S12
C...ROUTINE   BRIGHT...TO VARY INT FROM 2--7
C....EACH INTENSITY IS AN INCREMENT OF 5 KPSI
      INTEGER FCN,FIRST,END
      DIMENSION NBC(10)
      COMMON/LIMITS/XMIN,XMAX,YMIN,YMAX
      COMMON/AR/BRAY(4,600),STRESS(200,4)
            COMMON/SIHI/IVECT(1800)
  200 IF(FCN.EQ.3) GO TO 400
      CALL DISPLY(3,1,IVECT,FIRST,LAST)
      DO 45 J=2,NCD
      DO 45 K=2,NCD
      IF(NBC(K).GT.NBC(K-1)) GO TO 45
      NC=NBC(K)
      NBC(K)=NBC(K-1)
      NBC(K-1)=NC
      DO 66 M=1,2
      T=BRAY(M,K)
      BRAY(M,K)=BRAY(M,K-1)
      BRAY(M,K-1)=T
   66 CONTINUE
   45 CONTINUE
      DO 38 I=1,NCD
      NC=NBC(I)
      NC=((NC+3)/5)
      IF(NC.GT.7)NC=7
      IF(NC.LT.2)NC=2
      NBC(I)=NC
   38 CONTINUE
C.... NOW INT IS SET TO STRESS  MAGNITUDES
      DO 99 N=2,7
      K=500
      DO 88 I=2,NCD
      IF(NBC(I-1).LT.NBC(I)) GO TO 77
      K=K+1
      DO  122 J=1,2
  122 BRAY(J,K)=BRAY(J,I)
   77 CONTINUE
   88 CONTINUE
      NB=500
      FIRST=1
      END=K
      INT=NBC(1)
      ITAG=N
      L1=2
      NCD=K
      NUMB=K
      CALL S3(L1,NUMB,NCD)
      CALL VECTOR(1,BRAY,NB,END,FIRST,LAST,INT,0,.FALSE.)
      CALL DISPLY(FCN,ITAG,IVECT,FIRST,LAST)
   99 CONTINUE
      PAUSE 2
      RETURN
  400 FCN=3
      DO  101 ITAG=2,7
      FIRST=1
      NB=500
      END=600
      CALL DISPLY(FCN,ITAG,IVECT,FIRST,LAST)
  101 CONTINUE
      RETURN
      END
