67 



iKii'lliwaid Iroiii Kiiicon to Vciitu on tlit' Aliii<'ii(l;ir<'s Uiver in tlio northern 

 watershed. Aside from the "ojos do agua" along tlie edge of tlie cienegas 

 sl\irting tlie southern coast there are tAvo notable places where under- 

 gi-ound rivers find an exit. The one at Vento, as already mentioned, sup- 

 plies the entii'e city of Havana with its water, the otlier serves to make 

 the region al)out Guines a garden, its waters being used for irrigation. 

 Other snl)terranean rivers in all probal)ility have a sub-aqueous exit to 

 the south. 



The large spring at Vento is the only one on the northern slope as far 

 as I know. The origin of tlie supply Issuing from the Vento Spring has 

 not been traced. P.ut the region iioitli of tlie Alniendares River, being 

 shut out from a possible contributing source, it undoubtedly derives its 

 water from the tongue of the system of underground sti-eams thrust into 

 the northern slope. An examination of the best available map and the 

 levels of the Western and United Havana Railroads make it seem quite 

 certain that the Vento S])rings derive their water from the region imme- 

 diately south of Vento and north of Rincon and Be.jucal. This region 

 contains vai-ious sinks, without surface outlets, as well as dry sink-holes. 

 A notable sinkhole in tills region is that at Aipiada on the United Havana 

 Railroad. This Is very broad, shallow and dry during the dry season, but 

 the water rises to stand over ten feet deep on the railroad tra<-k during 

 sonie of the wet seasons. All of these pi'ol)ably drain Into the Vento 

 Spring. 



It behooves the health authorities of the city of Havana to exer- 

 cise the strictest guard over the region between \'ento on the north and 

 Rincon and Bejucal on the south. .\ny contamination of sink-holes in 

 these regions is sure, during tlie wet season at least, to contaminate tlie 

 underground streams leading to A'ento. An examination of the under- 

 ground channels in the Uost River region of Indiana has shown the main 

 undci'ground cliann(>ls to lie jirovlded with minierous smaller tributary 

 channels which in ordinary weather do not carry Avater Ijut Avhich do 

 carr.v water Into the main stream after a long rain. At such a time any 

 tilth that may have accuiiiulated In any of the sink-holes over one of the 

 tributary streams is sure to tind its way into the main stream. The same 

 is very probabl.v true of the Vento supply, although on account of the 

 nature of the region It is not possible to follow the underground channels. 

 At present some of the sink-holes 1)etween Rincon and Vento are used as 

 cesspools and receivers of scAvage. 



