1835.] EARLY PERUVIAN WATER CONDUITS. 355 



Chilian climate any great difficulty. We must also admit 

 on this notion (and this perhaps is a greater difficulty), that 

 man has inhabited South America for an immensely long 

 period, inasmuch as any change of climate effected by the 

 elevation of the land must have been extremely gradual. 

 At Valparaiso, within the last two hundred and twenty 

 years, the rise has been somewhat less than nineteen feet : 

 at Lima a sea-beach has certainly been upheaved from 

 eighty to ninety feet, within the Indo-human period : but 

 such small elevations could have had little power in 

 deflecting the moisture-bringing atmospheric currents. Dr. 

 Lund, however, found human skeletons in the caves of 

 Brazil, the appearance of which induced him to believe that 

 the Indian race has existed during a vast lapse of time in 

 South America. 



When at Lima, I conversed on these subjects * with Mr. 

 Gill, a civil engineer, who had seen much of the interior 

 countr}'. He told me that a conjecture of a change of 

 climate had sometimes crossed his mind ; but that he 

 thought that the greater portion of land, now incapable 

 of cultivation, but covered with Indian ruins, had been 

 reduced to this state by the water-conduits, which the 

 Indians formerly constructed on so wonderful a scale, 

 having been injured by neglect and by subterranean move- 

 ments. I may here mention, that the Peruvians actually 

 carried their irrigating streams in tunnels through hills 

 of solid rock. Mr. Gill told me, he had been employed 

 professionally to examine one ; he found the passage low, 

 narrow, crooked, and not of uniform breadth, but of very 

 considerable length. Is it not most wonderful that men 

 should have attempted such operations, without the use 

 of iron or gunpowder? Mr. Gill also mentioned to me 

 a most interesting, and, as far as I am aware, quite 

 unparalleled case, of a subterranean disturbance having 

 changed the drainage of a country. Travelling from 

 Casma to Huaraz (not very far distant from Lima), he 

 found a plain covered with ruins and marks of ancient 

 I ultivation, but now quite barren. Near it was the dry 

 ( ourse of a considerable river, whence the water for 



* Temple, in his travels throuRh Upper Peru, or Bolivia, in going from Potosi 

 to Oruro, says, " I mw many Indian villages or dwclUnjfs in ruins, up even to 

 the very tops of the moimtaiiis, attesting a former population where now all is 

 desolate." lie makes similar remarks in another place ; but I cannot tell 

 whether this desolation has been caused by a want of population, or by an 

 altered condition of the land. 



