LAND-SLIDES. 267 



Brackenridge says, in speaking of the mountains about Rio : 



" They sometimes let loose upon the valleys what is even more dreadful than 

 the avalanche ; huge masses of earth, loosening from the rock by the moisture in- 

 sinuated between them in the rainy season, slip down and overwhelm everything 

 below. It is not long since an instance of this kind occurred, when more than 50 

 famiUes were buried alive." * 



Liais says that in March, 1859, a violent rainfall (14 centimeters in 

 two hours) caused a great land-slide on the Morro do Castello in Rio de 

 Janeiro f and at a great number of places on the east side of the bay. 



In 1866 several houses are said to have been overwhelmed by a land- 

 slide near Petropolis. J In 1881 I was told by a German living at Petrop- 

 olis that one of the reasons the German colonies established there had 

 never succeeded w^as that the hillsides they tried to cultivate were so 

 given to sliding. 



Caldcleugh mentions " a space of hardly less than three acres '' having 

 slipped from its original position at the old topaz mines near Ouro Preto, 

 state of Minas Geraes. § 



On the railways through the mountainous regions land-slides are nec- 

 essarily superinduced by the cuts where the binding offered by the roots 

 of plants and the support of the natural slope of the decomposed rocks 

 have been removed. The torrential rains precipitate some of these slides 

 every year, though they are now less common than formerly, owing to 

 the care exercised by engineers to prevent them. In some places the cut 

 for the roadbed so disturbed the slope above, that the line of the road has 

 actually been changed in order to evade the constant slipping of the earth 

 upon the railway track. 



In tunneling for the Central (formerly the D. Pedro II) railway on the 

 Serra do Mar — 



" Constant danger and difficulty arose from the breaking in of the rock, and in 

 one instance the whole mountain spur through, which the tunnel had been driven 

 parted from the main mass and sliding down obliterated the work, so that it was 

 necessary to begin the perforation again." || 



A good idea may be had of the great number of slides along the rail- 

 ways in a single month from an article by Dr J. A. dos Santos published 

 in Rio in 1880. On the Sao Paulo lines all trains were stopped except 

 on two roads ; on the Ituana line traffic was suspended several days ; on 

 the English line passenger traffic was suspended for three days and freight 



* Voyage to South America performed by order of the American Government in the years 1817 

 and 1818. By H. M. Brackenridge. London, 1820, vol. i, p. 104. 

 t Climats, geologie, faune du Br6sil. E. Liais. Paris, 1872, p. 13. 

 t Burton's Highlands of Brazil, vol. i, p. 73. 



§ Travels in South America. Alexander Caldcleugh. London, 1825, vol. ii, p. 229. 

 Il A Journey in Brazil. Professor and Mrs Louis Agassiz. Boston, 1868, p. 528. 



