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The current study conducted to investigate the anatomical and histological structure of the cornea in sparrow hawk accipiter nisus. By using an optical microscope and histological stains. Anatomical results showed that the cornea composed of two parts, the peripheral cornea and the central cornea, and there was variation in corneal thickness according to the anatomical region. Histologically, the cornea consists of five layers. The first layer of the central cornea consists of non- keratinized stratified squamous epithelial tissue composed of four rows of cells. Whereas, Bowman's membrane appeared clear and thicker on the dorsal side than on the ventral side. The corneal stroma consists of collagen fibers arranged in three secondary layers within the stroma. The corneal stroma also distinguished by the presence of fibroblast cells, which randomly distributed among the collagen fibers. The Descemet membrane appeared clear and equal in thickness between the dorsal and ventral sides. The endothelium tissue appears in the form simple squamous epithelia. The histological structure of the cornea root seemed similar to its formation in the central cornea. Still, it characterized by the presence of pigment cells spread in the stromal corneal root. Among the distinct results that appeared in this study is the presence of blood vessels spreading in the root of the cornea. The study concluded that the anatomical and histological structure of the cornea in this bird distinguished by some specialties that contribute to increasing the effectiveness of the function of the cornea in this bird.

The reduction of local scour downstream bridge piers got a massive concentration by several studies. In this study the D/S edge of the rectangular section semicircular bridge pier was reduced. This reduction was built to determine its influence on the local scour D/S these piers. Four models of the piers were manufactured from thermo-stone. The upstream semicircle diameter was fixed by a 10 cm, while the D/S diameter was changed to 4,6,8 and 10 cm . The experimental results provide evidence that the reduce of the D/S diameter of the pier leads to decrease the D/S scour depth and length . Moreover, in its place the sand was noticeably deposited D/S the pier. The experimental results was used to develop two liner empirical relations the first to estimate the ratio of maximum scour depth to U/S diameter of the pier ds/d1 . While the second to estimate the ratio of the length of scour to U/S diameter of the pier X/d1 , in terms of the ratio for D/S diameter of the pier to U/S diameter of the pier d2/d1 , length of the scour U/S the pier to D/S diameter Z1/d2, maximum width of scour to D/S diameter Z2/d2.