ALBI, Railway Bridge at, see the colour plate facing page 8. ALCÁNTARA, in Spain, and the Puente Trajan over the Tagus; a wonderful Roman bridge, 6, 16, 153, 183 _et seq._, 212, 321. ALCÁNTARA at Toledo, a famous old war-bridge, 285-7; and see the two colour prints facing pages 32 and 284. ALCANTARILLA, in Spain, its most interesting Roman war-bridge, 30, 182, and 367-8. ALDEGUELA, JOSÉ MARTIN, a great Spanish bridge-builder of the 18th century, 280 _footnote_. ALDERSHOT, its vulnerable bridges on a single-line railway that runs toward Southampton, 336 _footnote_. ALEXANDER THE GREAT, his possible influence on bridge-building in India, 272. ALEXANDRINE AQUEDUCT, the decoration of its wall surfaces with coloured tufa arranged in geometrical patterns, 190. ALGERIA, Pont Sidi Rached at Constantine, built between 1908 and 1912, 53. ALI VERDI KHAN, the Bridge of, at Isfahan in Persia, over the Zendeh Rud, 212, 268-70. ALLBUTT, SIR CLIFFORD, on the immaturity of modern science, 7. ALLEN’S “History of the County of York,” 243 _footnote_. ALONSO OF SPAIN, in 1258, repaired the Alcántara at Toledo, 287. ALTAMIRA CAVERN, near Santander, its prehistoric art relics, 62. AMBROISE, PONT, over the Vidourle, a Roman bridge, now a ruin, 82, 177. AMERICA, SOUTH, primitive bridges there, as described by Don Antonio de Ulloa, 135, 146-7. AMERICA, UNITED STATES OF, their timber bridges, 142-3; their defenceless modern bridges, 352-4. AMMANATI, BARTOLOMEO, Florentine architect of the 16th century, his great bridge over the Arno, 222, 316-17. AMSTERDAM, the Hoogesluis at, a strumpet of a bridge, 323. ANGERS, a suspension bridge at, how it gave way when soldiers were passing across it, 144 _footnote_. ANCHORAGE OF CHAIN BRIDGES, at Auhsien in China, 346-7. ANCUS MARCIUS, and the Pons Sublicius, 64, 140. ANGELL, NORMAN, a firm believer in the illusion called peace, 351. ANGELO, PONTE SANT’, at Rome, anciently the Pons Ælius, 194, 324. ANIO VETUS, Roman Aqueduct, its great height, 190. ANTIQUARIES, their aloofness from public interests, 9, 11; very often they mistake facts for truths, 9-11; their pedantry and its results, 11; their attitude to the Clapper Bridges over Dartmoor rivers, 100, 102, 103. ANTIQUARY, an old, his bad advice to young pontists, 8-10. ANTONIO DA PONTE, in 1588, began to erect the Rialto, 212. ANTS, their intelligence, 110; they bore tunnels under water and make bridges over running streams, 122; the fertility of their minute cerebral ganglia contrasted with the dullness of the average human brain, 239-40. APATHY, BRITISH, in matters of national defence, 15, 16, 33 _footnote_, 336 _footnote_, 350, 351, 355, 359, 360. APOLLODORUS OF DAMASCUS, great Roman bridge-builder, 129-30, 131, 344.