The Cordova to Malaga Railway, 121 miles, is extremely easy in point of construction, except for 6¼ miles at the passage of the Guitanas, where there are no less than twelve tunnels and six great bridges. In one of the tunnels a singular circumstance was discovered during construction. The miners suddenly came upon a _crevasse_ or split in the mountain which extended from its lofty and precipitous summit to a great depth beneath the part bored through. The space is traversed by a bridge, the only one in the records of tunnels that we remember to have met with.
There is one very long canal tunnel in Spain—the Canal of Urgel—between the Ebro and one of its affluents, the Segro. This canal is 90 miles long and the tunnel is of the length of 5,230 metres.
The grandest canal in Spain for water supply is the “Canal of Isabel II.” It furnishes the supply for Madrid. It is built after the system of the ancient Romans—that is, aqueducts constructed in masonry arched over. Its total length is 45 miles. It has besides, thirty-one tunnels, partly cut straight through rocks which the canal traverses, and partly side-cut tunnels (one is five-eighths of a mile long) for obtaining water. At the present time, when the question of supplying London and other important cities with water is much agitated, it may be well to mention that by means of this canal 200,000 cubic metres of water, or 600 litres (a litre is about a quart) per inhabitant are brought to Madrid daily. Of these 600 litres 100 per head is for domestic use, and 500 for irrigating the districts adjoining Madrid. The quality of the water is said to be excellent; indeed it is alleged that if the air which it contains were abstracted it might be considered as distilled water. The pressure of the water in the conduits is almost without exception sufficient to raise it to the upper stories of the highest houses in Madrid. In some quarters of the city it could rise 75 yards above them. There are two road tunnels in Spain, one on the road between Grenada and Motril, 300 metres long, and one on the Pyrennean road between Barbastro and Benasquez, the length of which is 90 metres.
Spain, for a country with a population under 16,000,000, cannot be said to be badly off for means of communication. The total length of roads in the kingdom on the 1st of January, 1867, was 4,137,640 miles of the first class, 3,265,700 of the second, and 1,908,112 of the third. About 2,800,000 are in course of construction. It is intended eventually to extend the road system of Spain to a total of about 22,500,000 miles. As already mentioned, the total length of Spanish railways on the 1st of January, 1867, was 3,182 miles.