In settlements, homes clustered close to the center of a town.

True blindness may be caused by trauma to the eye, severe conjunctivitis due to  ibr (infectious bovine rhinoceros) or pink eye or other infections, leptospirosis, lead poisoning, selenium toxicity, fungal infections, vitamin a  deficiencies, rabies, vitamin b12 deficiency, neoplastic of the orbit or  conjunctiva, cataracts, congenital malformations, etc.