An attempt to discriminate the styles of architecture in England : from the Conquest to the Reformation ; with a sketch of the Grecian and Roman orders /by the late Thomas Rickman (1881)
Rickman, Thomas, 1776-1841, Parker, John Henry, 1806-1884, Le Keux, John Henry, 1812-1896, Cattermole, George, 1800-1868, Mackenzie, Frederick, 1787 or 8-1854, Jewitt, Thomas Orlando Sheldon, 1799-1869, Starling, William Francis, Hacker, C., 19th cent, Carter, James, 1798-1855, Wilkinson, W. S, Smith, C. B · London : Parker and Co. · leaf 61
A segmental arch has its centre lower thanthe spring, [as in fig. 2.] A horse-shoe arch has its centre above thespring, [as in fig. 3.] Pointed arches are either equilateral, de-scribed from two centres, which are thewhole breadth of the arch from each other,and form the arch about an…