The longest railway tunnel in Belgium is that of Braine le Compte, 641 metres (705 yards). It cost £46 a metre. There are altogether eighteen tunnels along the 15½ miles of picturesque line of railway between Liege and Verviers; they are all short, none exceeding 400 metres in length; their cost was exactly £50 a metre forward. There is only one long tunnel in Switzerland, that of Hauenstein near Olten, on the railway between Basle and Berne, its length is 2,731 yards, and, notwithstanding the numerous difficulties which attended its construction, its cost was only £80 per yard. It might be expected that in an undulating country like Switzerland there would be a great many tunnels on its railways; such, however, is not the case, the larger proportion of the railways are constructed in the comparatively level valleys, and when engineers come upon rough ground, as a rule, they prefer stiff gradients to very expensive works. This, however is not always the case; witness the passage of the Jura from Pontarlieu towards Neufchatel; here there is the combination of expensive works with a steep ascending and then a steep falling gradient. These might have been greatly alleviated, if not altogether avoided, by a tunnel of comparatively short length; the engineer, it is said, wished to erect for himself, in this work, a monument _perennius ære_. He has succeeded. The longest tunnel upon a railway in Italy, now open for traffic, is on the Giovi incline, near Genoa, 3,225 yards, or five yards over two miles. The longest of the two on the Brachia pass of the Apennines, between Pistoja and Poretta, is (as already stated) 3,300 yards; the length of the next longest, on the same pass, is 2,860 yards. A tunnel longer by a few yards than that on the Giovi incline, is in process of construction on the branch which is to connect Naples by a direct line with the Adriatic. The tunnel Maggioni, between Florence and Rome, is 1,170 metres (1,287 yards) long. The natural undulatory, in many places almost mountainous, character of Spain, has rendered necessary the construction of numerous tunnels on Spanish Railways. The following is an abridgment of much interesting information on this subject, published by the Spanish Government last summer, and translated into French a few weeks ago.