Sketch of the Belamilla Intermarin P. San Luis Potosi, Thursday Sep. 20. Was to leave at 6.40 for Tampico but the train is two hours late. The I. L. P. Plain is one mass of mescal and we got near the Dos Rios pass and three came in. Arriving at Alonso 17 Kil. E. of I. L. P. there is Cretaceous and lime hills. In one of these quarries is shown a fine Trias deposit. The road rises rapidly for several Kilos. to Villan and the descends. Crest over about here. From Villan to San Lazaro it is rapid def down through a narrow gorge that gradually widens into a day narrow valley. From San Lazaro to Cerritos it is slower def down a former valley and from here we strike as before back from several of those narrow valleys leading into the one we are in. This is the first def for the open mesa through the Cretaceous of burned coals. The second def of the Cretaceous is probably not more than 20 to 40 degrees. These are the cuts other direction. The Plain keeps an orderway and is flat a nearly or