500 METEOROLOG-i: . 



to consult the old sportsmen of the country, and to refer to the 

 annals of the various parishes, to be satisfied that extensive forests 

 have been cut down in the whole of the surroundingf country : the 

 clearing, in fact, still continues ; and it is certain that the recession 

 of the waters, although much slower than il was in former times, has 

 not yet entirely ceased. 



A lake, situated in the same valley, to the east of Ubate, deserves 

 our particular attention. By means of baromt trie measurements, 

 made with extreme care, I found that this lake had precisely the 

 same level as that of Ubate. Nearly two centuries ago, it was vis- 

 ited by Piedrahita, Bishop of Panama, an author of great accuracy, 

 to whom we owe the history of the conquest of New Granada. He 

 states this lake to be ten leagues in length, by three leagues in 

 breadth ; but Dr. Roulin having had occasion, a few years ago, to 

 make a plan of the lake, he found it a league and a half in length, by 

 one league in breadth ; my own impression is, that at the time 

 Piedrahita wrote, there was but a single lake, extending all the way 

 from Ubate to Zimijaca, not two lakes as at present, a supposition 

 which would take away every thing like exaggeration from tiie state- 

 ment of Piedrahita. But the fact of the retreat of the waters of 

 these lakes is unquestioned ; the inhabitants of Zimijaca all know 

 that the village was founded close to the lake, whereas, at the pres- 

 ent time, it is nearly a league from its banks. Formerlv, there was 

 no difficulty in obtaining all the building timber that was wanted ; 

 the njountains w^hich rose from the valley on either hand were cov- 

 ered up to a certain height with the trees proper to these cold re 

 gions ; the oak of the Andes abounded; numerous myreias were 

 also in existence, from which abundance of wax was obtained : ^d^ 

 the present time these mountains are almost stripped of their trees, 

 an event mainly brought about by the eagerness to procure fuel in 

 manufacturing salt from the springs of Taosa and Knemocon. 



To these authentic facts, which I could multiply and su{>j)ort by 

 many others of a similar kind, it may be replied, that the diminution 

 of the water, incontestable as it is, might perhaps have taken j)lace 

 without the clearing away of the ft>rests. It may indeed be main- 

 tained, that the dr* ing up of the waters is owing to a totally ditfcr- 

 ent cause, altogether unknown to us ; that it must be ranked among 

 the numerous phenomena, the reality of which we perceive, but 

 without being able to render any account of their cause. 



I cannot, in the instance last quoted, as in that of the lake of Va- 

 lencia, refer to any increase of the lake connected with the suspen- 

 sion of agricidture, or the reappearance t>f the forest. I might, 

 however, adduce in favor of the oi)inion which 1 defend, the slow- 

 ness with which the decrease in the lakes of the valley of Ubat has 

 hitely gone on, and since the felling of trees in the neighborhood 

 has almost entirely ceased. Extensive plots of fertile ground are 

 now no longer left dry and available to the husbandman by the re- 

 reat of the lake ; he already begins to think of means tor obtaining 

 by artifice that which nature, assisted by the clearing of the country 

 presented him with in former times. In the year 1826 there was 9 



