Geography and Meteorology 269 



two of tnese were at the ocean terminals of the 

 Canal, Cristobal on the Atlantic, and La Boca, re- 

 cently renamed Balboa, on the Pacific. In addition 

 to these were the cities of Colon and Panama, which 

 although not in the Canal Zone politically, are yet 

 geographically so, and were placed within the san- 

 itary jurisdiction of the United States by treaty. 



Colon and Cristobal are situated on Manzanillo 

 Island, a fiat marshy piece of land the elevation of 

 which is approximately four feet above mean tide. 

 This island is largely a coral formation covered 

 with a layer of soil. There are no rivers or springs 

 on the island, and no wells. Formerly the only 

 source of water supply for Colon was rain water 

 and fortunately the precipitation in this locality 

 is very great, averaging 120 inches annually. 

 Some water was brought into Colon by rail and 

 stored for use. The towns in the Canal Zone de- 

 pended for their supply on adjacent rivers, streams, 

 and springs, which are plentiful in the Zone. Pan- 

 ama, Ancon, and Balboa (La Boca) are situated 

 at the southern extremity of the Canal. The 

 rainfall there is far less than on the Atlantic slope, 

 averaging about seventy inches per annum. The 

 stored rain water was therefore supplemented by 

 wells and aqueducts carrying surface and subsoil 

 water, with tanks for storage. 



