The Water-Horse Strikes Yazdegard

From D9.7, Yazdegard Is Killed by a Water-Horse. It illustrates D9.7.22–27:

D9.7.22
He took the saddle and the reins, and wentIn joy toward the steed, on taming bent.
D9.7.23
The horse stood so submissive to his will,It never moved a foot, but held quite still.
D9.7.24
The Shah put on the bridle; still it stayed,And stood at ease while he the saddle laid.
D9.7.25
He drew the girths and bound the saddle fast;No tremor through that great nahang had passed.
D9.7.26
He moved to fasten crupper at the rear;The flint-hoofed charger cried for all to hear.
D9.7.27
It lashed both hind feet hard against his head;His head and crown struck dust; the Shah lay dead.