Tanz's measured progress continued until he came to van Gogh's Self-portrait, 1889, oils, 65 x 54 cm., sometimes known as 'Vincent in the Flames'. The description in the catalogue read:' . . .Taut to the breaking point, it testifies to van Gogh's struggle to master his inward turmoil .... An expression of supreme equilibrium on the brink of the abyss.
Hartmann limited himself to the bare title and reference number, thinking that there would be no time for more. Mechanically, he started to move on to the next picture, but General Tanz lingered in front of 'Vincent in the Flames' longer than usual. He stared at the picture, or rather, he stared straight ahead and consequently--since it hung at eye level--at the picture.
Hartmann approached with due caution. Suddenly, he saw the General's right arm begin to twitch convulsively. His hand, twisted into a claw, groped its way upwards and clutched his forehead in a vicelike grip. His body, usually as erect as a ferro-concrete tower, tottered and threatened to collapse.
Hartmann rushed forward and grasped the General's left arm. Simultaneously, he felt the muscular flesh beneath his fingers grow taut as a steel cable. Tanz's arm jerked one way and then the other, throwing him off balance. Hartmann staggered back, his childlike eyes filled with astonished incomprehension.
Tanz turned to face him, looking as craggy and inaccessible as he had ever done. 'How dare you lay hands on me?' he asked softly, his eyes as cold as a snake's.
'Excuse me General, I thought ...,'Never do that again.'
Tanz spun on his heel and made for the next picture. Hartmann followed him. His mind was a whirl, but he managed to find his place in the catalogue again.