88 NOTES OF A BOTANIST CHAP. 



stream be swollen it is quite impassable, and 

 travellers have to wait till it abates. The whole 

 number of these crossings is twelve, and after 

 leaving it a tributary stream of scarcely less size 

 has to be crossed thrice in ten minutes. 



Many attempts have been made to find a way 

 which shall avoid the gorge of the Cachi-yacu, but 

 hitherto without success. Beyond this there is a 

 long painful ascent to a spring of clear water called 

 Potrero, where the traveller begins to emerge on 

 the grassy plateaux and declivities of the Campana. 



In imitation of the tambos or houses of rest and 

 refreshment placed by the Incas along their great 

 roads, the modern Peruvians have erected sleeping- 

 places wherever the pueblos are at too great a 

 distance to be reached in one day. To these also 

 they give the name of tambos, but they are as 

 inferior to the ancient ones as are the modern roads 

 to the solid structures of the Incas. They consist 

 of a roof supported on four bare poles, without 

 walls, but when large and well-made such shelters 

 answer their purpose tolerably well. Of course 

 they have no permanent occupants, and the only 

 thing a traveller can calculate on finding when he 

 reaches a tambo is fire, which is rarely allowed to 

 become extinguished, as it is the custom for those 

 who have last occupied it to leave their fire well 

 heaped up with rotten logs. A slight channel 

 is made round the tambo to carry off rain-water, 

 and the soil taken out serves to heighten the floor- 

 ing, which, being spread with palm-leaves or with 

 fern, the traveller extends thereon his mattress or 

 his blanket, and wrapped up in his poncho and 

 another blanket, may calculate on passing the night 



