'FOR' I.=1 'STEP' 1 'UNTIL' 2 'DO'
SCHWARM(-120.0,120.0,-80.0,60.0,
         1.0,5.0,100,TETRA)

'COMMENT' First pass = figure 16.,
' second pass = figure 18.
 No re-init of JI between
 eruptions.

for (let erupt = 1; erupt <= 2; erupt++) {
  for (let I = 1; I <= 100; I++) {
    TETRA(J2(-120, 120), J3(-80, 60), J1(1, 5));
  }
  // erupt 1 = fig. 16 (not drawn)
  // erupt 2 = fig. 18
}

Approximate rendering. P. 171: the same input as figure 16, SCHWARM(…,TETRA) twice, without reloading the generators. The first pass is figure 16, this second is figure 18 — two apples from the same tree. TETRA remains a reconstruction (body not in the book); JS1…JS6 are the usual book seeds, not those of the plate. Sheet 90° clockwise like the scan.

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