Sacramento daily record-union. [volume] (Sacramento [Calif.]) 1875-1891, 1884-01-19

the theory of DR.. George W. Barnes. OF
San Diego.
In 1879, the doctor concluded long and
careful observations of the hillocks, and sub
mitted his views to local society Of natu-
raj history. In the same year they were
reproduced by the american Naturalist.
Recently demand for the paper has justi.
fed its republication. 1t is now quite gen.
orally accepted by scientists as the true
theory of the cause of the hillocks, and
dissipates all the notions of sea action, In
dian building, etc.
According to DIR. Barnes. these protuber-
ances on our great plains were caused by
vegetable growth, but several agencies were
concerned. Each knoll marks the spot, he
holds, where formerly grew shrub or clus-
ter of plants, either the RhUs lourina, the
Simmondsia California;. or the Isoumer5s
arJorea. The first was the most frequent.
1t formed dense mass lying close to the
ground, with many branches setting out
from the earth level and throwing into the
ground beds of massive roots. The dis
tribution of the groups OF this plant bears
a striking resemblance to the disposition OF
the mounds on the plains. The shrubs
arrested dust moved by the winds, and the
fallen leaves added to the accumulation
that finally nearly covered the plant, and
thus the knobs grew in hight.
In exceptional cases the gopher wss an
adjunct of the wind in heaping up mate
rial. The plant sheltered the summit Of
loose earth and vegetable matter caught by
it prevented the action of the rains, the
intricate system of roots equally protected
the outlying base of the gathering knoll
from wash, while between the hillOcks the
natural erosion went on unobstructed.
Thus, he believes, the knobs grew and the
depressions increased. Finally the plants
were smothered to death by accumulations,
or they were swept by fires. Left unpro-
tected the rains and winds beat down the
summit considerably, and thus the base is
bro9dened by the wash, and all the while
the hollows are being deepened by erosion.
1t is strongly conhrmatory Of the doc
tors theory that he has frequently ex-
cayated the matted roots from the later
mounds, although no trace of Shem is found
in the older ones, So, too, his argument
finds justification by recalling the attention
TO the active agency of the wind in form
ing hillocks, as seen in the sand dunes OF
Scotland. We have noticed the like cause
and effect upon the sandy stretches of shore
along Lake Michigan, especially near its
southern extremity. It was hardly neces.
sary TO remind us that shrubbery and tim
Der everywhere impedes the drainage of
water from rainfall. The groups of shrubs
acting in this way served to diffuse the
water that would otherwise be concen-
trated into gulleys, As a minor agency
the doctor credits burrowing animals with
contributing to the hillocks by earth
thrown out from their excavations that
afterward A final suggestion he credits
to friend, shat the wind probably played
a part in exoavating between the shrubs of
which the mounds are sequence.
This theory for accounting for one Of the
marked peculiarities OF much of the plain
surface of California has been before the
scientific world so long without being over.
thrown, has met with such approvsl from
authorities OF weight, and is so in accord
with the reasonable, that it may now be
accepted as explaining the true cause for
the hillocks, concerning which there has
been so much speculation.