Mr. Crockett did not understand the rivers of Spain, many of which after a storm leap from their dry beds into raging torrents, and give rough-and-tumble lessons to bridge-builders. From Roman times to our own, these freakish waterways have inspired noble work, that cannot well be rated at too high a level. At Mérida alone a pontist can dream over the past for several months, not only studying the remains of three Roman aqueducts, upon which storks hold their parliaments, but making friends with two Roman bridges, one of which puts the Roman genius in scale with the Guadiana. It is a huge structure, not less than 780 metres in length, with sixty-four arches of granite. Books of reference mention eighty-one arches, but this number includes the relief bays for floods tunnelled through the piers above the cutwaters. Some writers believe that the greater bridge at Mérida was built under Trajan, while others give it to Augustus, who founded Mérida as a home of rest for the veteran soldiers of his last campaign. In 686 the Visigoths restored this bridge; in 1610 it was repaired by Philip III; in 1812, during the siege of Badajoz, seventeen of the arches were wrecked in order to close the river. At the northern end we find a Roman castle, now in ruins, so we are able to study a battle-bridge dating from those times when Rome turned wars into colonies. The Roman bridges of Spain may be divided into five classes:-- 1. Those which are low and many-arched, as at Mérida and Salamanca. 2. Those which have two or three arches with shelving parapets and roads, as at Alcantarilla[70] and also near Villa del Rio;[71] 3. One or two with a single arch, as at Ronda; 4. Several in which Roman and Moorish masonry are combined, as at Córdova; and 5. There is one Roman bridge so lofty that its parapet is separated from the river-bed by a distance of more than fifty-nine metres. I refer to the famous Puente Trajan over “the melancholy Tagus” at Alcántara. This herculean masterpiece has six arches, his length is a hundred and eighty-eight metres, and the roadway is eight metres wide and quite level. A triumphal archway thirteen metres high stands in the middle, but I regard its Roman origin as doubtful, as the design is not quite in scale with the majesty of the bridge.