Machicolations, openings between the corbels that support a projecting parapet, or in the floor of a gallery or the roof of a portal, for shooting or dropping missiles and boiling liquids upon assailants attacking the base of the walls. They were used in the defence of old bastille bridges, and silly modern engineers have copied them as dummy ornaments with which to decorate trumpery defenceless gateways and towers, 275, 323.

Orthez, Vieux Pont, mediæval war-bridge, 278-9. There are two conflicting accounts of the part played by this bridge in the battle of Orthez, February 27th, 1814. One of them says that the bridge was neutralised by agreement in order to spare it from destruction; the other account declares that the solidity of the stonework baffled the French attempts to break it down. Anyhow, the bridge was not used in the action. Hill crossed well above it, and Picton and Beresford below. Napier says: “Hill, who had remained with 12,000 combatants, cavalry and infantry, before the bridge of Orthez, received orders, when Wellington changed his plan of attack, to force the passage of the Gave, partly in the view of preventing Harispe from falling upon the flank of the sixth division, partly in the hope of a successful issue to the attempt: and so it happened. Hill, though unable to force the bridge, forded the river above at Souars, and driving back the troops posted there, seized the heights above, cut off the French from the road to Pau, and turned the town of Orthez.”

Parapets, low walls or railings serving to protect the edge of a bridge; they rest on the outer spandrils; sometimes they project beyond and need brackets or corbels, like the Pont Neuf at Paris, 321-2, and plate facing page 320. Often in the Middle Ages some parts of the parapets were crenellated, as they are above the angular piers of the Valentré at Cahors, see the colour plate facing page 264; even some modern defenceless bridges have battlemented parapets, for the imitative silliness of industrial engineers delights in foolish make-believe. Parapets cannot be studied with too much care, so there are frequent references to them throughout this monograph. Some Roman bridges were built without parapets; there is an example near Colne, 162, 164; and many of the gabled bridges in Spain repeat in a giddy manner this dangerous defect, 27.

Paris and her Bridges, 225, 321-2. Here is a fine subject for a book. There is a good reference to the Paris bridges of the year 1517-18 in the “Revue des Deux Mondes,” xlvii., Sep., 1908, p. 467. Five bridges existed then, three stone structures, and two of wood; and all of them had houses from one end to the other. Tolls were charged and they belonged to the King. Several illustrations of Paris bridges will be found in Lacroix, “Manners, Customs and Dress during the Middle Ages.” On page 321 there is one of the year 1500; see also in the same book pp. 302, 316, and 471.

Parliament of Taste, a, necessary in all large towns for the discussion of art in all matters that concern the public intimately, 324-5.

Peace, considered in her relation to the varied strife circulated by roads and bridges. She is an illusion of the mind and belongs to a routine of idle sentiment, vii, because every phase of human enterprise claims a battle-toll of killed and wounded and maimed, vii, 3, 4, 33-6; see also section ii, Chapter I, 14-52, and 333, 351, 360-1.

Perforated Towers on bridges; modern engineers have passed suspension cables through towers instead of passing them over the summits, 346, 354.

Piers of Bridges, 114, 200, 264, 316, 338, 341, 342, 353, 354. There are other references also, but the reader will be able to follow the history of piers from the natural bridge of stepping-stones through the many changes and defects mentioned in the text. To-day, with the rapid improvements in airships and aeroplanes, new armoured piers will have to be designed, strong enough to bear the great weight of a roofed superstructure of armour-plate steel, yet not thick enough to obstruct rivers. Now that bridges are as vulnerable as Zeppelin sheds, engineers have an excellent chance to serve their countries well by inventing new and powerful bridges. How to protect piers—at least as much as possible—from direct artillery fire is one very difficult problem; how to protect them from falling shells and bombs is another. When London is fitted adequately with new defensive bridges her river will be as impressive as a fleet of super-Dreadnoughts. See also “Abutment Piers.”