Eye chart smaller towards the bottom of the chart. The person removes any glasses or contact lenses, and stands or sits a standardized distance from the chart (e.g., 20 feet for the Snellen chart). The person is then asked to identify the optotypes on the chart, starting with large rows and continuing to smaller rows until the optotypes cannot be reliably identified any more. The row in which the person can reliably identify symbols defines the visual acuity. One eye is tested at a time. Practically, this is accomplished by covering the other eye with a hand, piece of paper, or a
Letters of the Living is 19. The word Wáḥid means "One". The Báb used this term as a reference to God and his Manifestations. The Letters are listed here in the order given by Nabíl in The Dawn-Breakers, and supported by Qatíl al-Karbalá'í except where indicated: Muḥammad-Ḥasan Bushrú'í was the second Letter of the Living, and the brother of Mullá Husayn. He, his sons, Muḥammad-Báqir Bushrú'í, and Mullá Ḥusayn travelled to Shiraz in search of the Qá'im; where the Báb revealed his message. He was killed during the Battle of Fort Tabarsi. Bábís consider him a martyr. Muḥammad-Báqir Bushrú'í was the third Letter of