The Banks of the Bio-Bio. 99 



most of the railway cuttings were through a clayslate roclc, which 

 alternated with bands of black shale, and occasionally exhibited 

 thin seams of coal. Further on, and throughout the rest of the 

 journey to Angol, the cuttings were through banks of sand exhi- 

 biting horizontal stratification, and being apparently of fluviatile 

 origin. A run cf two hours brought us to the junction station 

 of San Roscndo, from whence the northerly line to Cliillan, 

 Talca, and Santiago, and the S.E. Hne to Angol diverge. Here 

 we breakfasted, and stretched our legs by a stroll. Immediately 

 on resuming our journey we crossed the Lara, — a tributary 01 

 the Bio Bio, — and then continued our course along the right 

 bank of the main river, until we had just passed the station o\ 

 Santa Fe. Here the line made a short semicircular sweep, and 

 crossed the Bio Bio by a low wooden bridge of about two hundred 

 yards in length. Clark, the driver, told us that during freshets the 

 water rose about fifteen feet above this bridge, completely stopping 

 the traffic. On asking him why they did not build a strong 

 high level britlge, he replied that a rude wooden structure such 

 as the present one cost little, and when swept away could be 

 readily and cheaply replaced ; but that a bridge of durable style 

 would take too long to pay the cost of its own construction. 

 This explanation may not at first sight seem very lucid, but it 

 is worthy of consideration, for the principle which it involves is, 

 I fancy, applicable to many of the affairs of Chili. 



We had now entered the great central valley of the ccuntr}-, 

 a broad plateau interposed between the coast range and the 

 Cordillera, and extending in one unbroken sheet of fertile land 

 from here to Santiago. Before us now, as far as the eye could 

 penetrate, lay a straight level track, so Mr. Clark turned the 

 steam full on, and the "Quillapan" responded to the tune of forty- 

 five miles an hour. When about a mile or two from a desolate 

 station called " Robleria," we were rapidly approaching a long 

 wooden bridge, when we saw a man appear on the track just 

 on our side of the bridge, and step leisurely from sleeper to 



