He was an imbecile.

William Thomas Andrews was a dwarf seventeen years old, whose head measured in circumference 35 inches; from one external auditory meatus to another, 27 1/4 inches; from the chin over the cranial summit to the suboccipital protuberance, 37 1/2 inches; the distance from the chin to the pubes was 20 inches; and from the pubes to the soles of the feet, 16; he was a monorchid.

James Cardinal, who died in Guy's Hospital in 1825, and who was so celebrated for the size of his head, only measured 32 1/2 inches in head-circumference.
The largest healthy brains on record, that is, of men of prominence, are those of Cuvier, weighing 64 1/3 ounces; of Daniel Webster, weighing 63 3/4 ounces (the circumference of whose head was 23 3/4 inches); of Abercrombie, weighing 63 ounces, and of Spurzheim, weighing 55 1/16 ounces.

Byron and Cromwell had abnormally heavy brains, showing marked evidence of disease.
A curious instance in this connection is that quoted by Pigne, who gives an account of a double brain found in an infant.

Keen reports finding a fornix which, instead of being solid from side to side, consisted of two lateral halves with a triangular space between them.
When the augmentation of the volume of the cranium is caused by an abundant quantity of serous fluid the anomaly is known as hydrocephaly.
In this condition there is usually no change in the size of the brain-structure itself, but often the cranial bones are rent far asunder.