122 CAKEIZO SACKETT'S WELLS. 



at the foot of such lofty, rough crested hills, rain, indeed, must be scarce, yet the evidences 

 of running water are displayed in the base of the triangular valleys leading out from the 

 rano-e, where large stones are washed out of the clay and sand and heaped together, the result 

 of existing causes. 



The temperature at Carrizo on the 3d June at noon was 100° Fahrenheit, and rose to 102" 

 later in the day. The effect of this heat was visible on the stream, which ceased flowing about 

 11 o'clock, and did not recommence until near 4 p. m., being absorbed or evaporated during 

 the interval ; two miles below it completely disappears in the sand. Five miles below camp 

 is the high terrace mesa, on gaining which may be seen the desert, as far eastward as the eye 

 can reach. To gain this the river bed was travelled down and its direction followed, for a few 

 miles, where the valley widened into a flat water bottom, the reservoir of the Carrizo ; in front, 

 was the denuded wall of the sands and clays, forming the terrace alluded to, and on the west 

 lay the volcanic rocks, which we were leaving behind, and which stretch out eastward in 

 isolated mountains, forming an unconnected chain, and by contrast to the even surface of tbe 

 desert resembling, what no doubt they were at one time, headlands and promontories of a bold 

 shore jutting out seaward. 



From the edge of the tcrace to Sackett's wells is about twelve miles. The soil along the 

 trail is made up of rounded quartz pebbles, grains of felspar, and larger pieces of the minerals 

 mixed ; a yellowish brown fine sand, with some plates of mica, and occasionally small masses 

 of purplish felspar porphyry, all rounded and well polished. Mr. Wm. P. Blake, in Lieut. 

 Williamson's Eeport, 1853, (H. Doc. 129,) no doubt gives the true explanation of the polishing 

 of these pebbles by the attrition of the loose sands, drifted by the winds. 



The unconnected chain of igneous rocks, referred to above, run out about forty-five miles 

 into the desert. One of these lies north of the trail, and one to the south, separating it from 

 the Gulf of California. One of the most remarkable of these is "Signal mountain," which 

 serves as a landmark to travellers from Fort Yuma to San Diego. These hills, judging from 

 their outline, are granitic and porphyritic, with trachyte. Although at a distance they appear like 

 a connected range, yet, when examined carefully, it may be seen that many of them drop 

 down at their extremities, and can be travelled round. Indeed, there cannot be truly said to 

 be any distinct range running eastward from the Sierra Nevada, the general chai-acter of the 

 country being a series of extended plains, separated from each other by isolated ridges or lone 

 hills, whose general direction is north 40° west, and south 40° east. 



The water supply at Sackett's wells consists of three wells sunk in an arroyo bed, which 

 itself lies four feet below the general level ; the wells are about six feet deep, and the water 

 oozes in about five feet down, flowing through a thin stratum of sand which overlies the clay bed 

 constituting the bottom of the wells. Should this last be cut through, the water sinks, and it 

 would be necessary to go several feet down to meet another clay layer. A fourth well was dug 

 at this time by a Mexican party travelling along. The water is good, not saline, and agreeable 

 to the taste ; it oozes out of the sand layer slowly but steadily, requiring six minutes to fill a 

 two-gallon pail. In one of the wells a barrel has been sunk, which should be done with all, and 

 an adobe building should be raised around them. The clay at the bottom of the wells is a 

 yellow, tenacious argil, and advantage might be made of it for brick manufacture, or using it 

 merely puddled as a material for the sides of the wells. 



From Sackett's wells to Alamo Mocho is thirty-five miles, passing by Lagoons, the trail lying 

 along a heavy sand road. The sand is fine, white, rounded quartz, like beach sand ; the clay 



