LAGOONS-—ALAMO MOCHO. 
123 
gradually disappearing the greater the distance from Sackett’s wells. In the proximity of the 
Lagoons the trail was on hard clay, and thence to Alamo Mocho it was mostly sand. This 
may he looked upon as the most sterile part of the whole desert, on many thousand acres there 
not being a blade of any vegetable growth. In several places a thin pellicle of clay, two to 
three inches deep, covers the surface, over which are scattered thin and worn specimens of 
Anodonta, and some small univalve G-asteropods. 
The southeast wind, rising in the afternoon, and blowing with considerable force, carries 
quantities of the fine sand with it, rendering it intolerably hot and scorching to the eyes; 
raising the temperature often to 115° Fah. 
The u Lagoons,” which are occasionally filled by overflows of the Colorado river, (distant 52 
miles,) were, at the period of visit, perfectly dry at Alamo Mocho, so called from the stunted 
and deformed cotton-wood tree near the springs ;* the water is in the bed of the New river, so 
called, as being the new course which the Colorado took in its overflow of 1849. The channel 
bends at this point, and is considerably below the level of its bank upon one side, where yellowish 
red stratified sand, 35 feet high, abut upon its edge. A new well has been sunk lately by the 
United States goverment, which is 22 feet deep, and yields an ample supply of water, not less 
than 500 gallons being removed in 2^ or 3 hours ; which, though it had an evident effect in 
lowering the well, yet its place was quickly supplied by a fresh influx of water. The well is 
defended by a wooden shaft and plank work to keep the sand from caving in, which is carried 
up 4| feet above the level of the surface ; a bucket and windlass would be a great boon to this 
spot, although found difficult to keep them. Two older wells are at a few yards distance along 
the same line. In one, the timbers have yielded and decayed, and the well is useless ; the other 
is in good order, but does not yield so large a supply as the new well. 
The whole level plain of the desert at Alamos slopes gently to the south, and in this direction 
also runs New river bed to meet the Colorado. The line of the bed can be traced by the cotton¬ 
woods and mesquite, which are only found growing there. On the level of the desert there is 
nothing but obione and larrea, the absence of vegetation being thus shown to be due, not to 
any infertility of the ingredients of the soil, but to the absence of sufficient moisture at the time 
when vegetable growth requires it. 
There is much more moisture in the air at this part of the desert than further west, at Carrizo. 
Hills 8 and 10 miles off were indistinct and hazy in outline, neither were the stars so distinctly 
visible; but no dew falls at night, the earth not cooling down sufficient to deposit the moisture 
from the atmosphere, consequently vegetation suffers almost as much as if the air were wholly 
deprived of it. Low clouds form in the north, near the horizon, and interchange sheet lightning 
in distant flashes.f 
The gravel pebbles of the desert are made up of volcanic and silicious material, chiefly the 
former, of which the reddish porphyry is most abundant; hyalitic quartz pebbles are common, 
with hornstone, chalcedony, phrenite, and chabasite, all rounded and polished by attrition so 
as to be perfectly smooth to the touch ; small fragments are also scattered about there. 
The trail from Alamo Mocho to Cook’s well is along the bank of the New river. The surface 
of the trail between these two waters (22 miles) is more undulating than the former portions of 
ft “ Mocho,” Sp. lopped, maimed—by many this word has been mistaken as being “mucho”—plentiful—but cotton, 
woods are not abundant here ; it is too dry a situation for them, while the disfigured tree is not many yards distant from 
the well. 
f These phenomena occurred during the prevalence of the south wind, which, blowing from the Gulf, may have produced 
a condition of atmosphere not often found in this region. 
