ISOSEISMALS: DISTRIBUTION OF APPARENT INTENSITY. 185 
tuff and seems to be free from water. A slicken-sided wall on the east shows a very 
smooth surface in spite of the soft rock. Striee near the top run N. 13° W. with a pitch 
of about 24°. The slide seems to have taken off some of the top of the ridge; that is, 
it started a few feet down the south slope of the ridge, cut its way thru a fir forest and 
dammed Maacama Creek with rocks and trees. Either two successive slides occurred 
or else the upper part of the moving mass was arrested part way down, for a bank with 
the vegetation of the top rests across the slide about one-third of the way down. (See 
plate 124a, 3B.) 
This slide was subsequently visited by Mr. G. K. Gilbert, who contributes the following 
supplementary note: 
At Maacama schoolhouse, I saw the large landslide described by Professor Holway. 
The rocks involved are in layers, with a dip of about 30° in the direction of the slide. It 
is therefore probable that the slide was partly determined by the dip, tho it seems to have 
been further determined by the erosion of the valley of Maacama Creek. The shock at 
that point was notably strong. A young man living close by told me that he was watering 
two horses at the time, and kept his feet only by holding on to a pump. Both horses were 
thrown down. The house of Mr. Stimson was thrown from the pegs on which it stood, and 
all brick chimneys in the neighborhood were broken. He and others mentioned numerous 
cracks in the bottom lands a mile to the north, and especially in the bottom lands of the 
Russian River at its neighboring large bend. 
Geyserville, Sonoma County (R. 8. Holway).— Shock reported north and south and 
northwest and southeast. Several brick buildings were badly cracked and tops of fire 
walls thrown down. The northwest wall of a butcher shop (brick) was thrown out 
against an adjoining frame building, which saved the brick building from an entire fall. 
Half or more of the chimneys were reported down. Goods were commonly thrown 
from shelving in stores. The cemetery 1.5 miles northwest in the low hills was not dis- 
turbed. The bridge across the Russian River at this point was unhurt. The town is on 
the west side of the river, on alluvial terraces. 
Cloverdale, Sonoma County (R. 8. Holway).— The upper walls of a brick building 
nearly opposite the United States Hotel were cracked so as to necessitate partial rebuild- 
ing. A 2-story brick building on First and West streets was unhurt except for cracked 
plastering. The shock was reported north and south; goods were thrown north and 
south from the east and west walls. In a 1-story brick building at Broad and West streets 
goods were thrown from the wall facing north. In the grocery opposite the United 
States Hotel goods were thrown mostly from the wall facing south. The inspector re- 
ports that he has condemned four-fifths of the chimneys, but most estimates agree 
that not over one-fourth fell. Mr. Scott reports that he went out-of-doors during 
the shock and that distinct waves in the ground could be seen moving from the west 
toward the east. The cemetery is on a knoll on the bank of Russian River, and suffered 
no damage except the fall of a vase from the top of a tall monument. ‘This fell to the 
north. 
(M. C. Baer.) On or about 9" 30" p.M., April 11, a slight shock (class III) was felt. 
The general direction seemed to be east and west and to have a trembling motion. The 
next shock came at 5" 13" a.m. on April 18, and was of about class VIII. The motion 
was at first oscillatory, but seemed to end up in a series of jerks. There did not seem 
to be any general direction. All chimneys were cracked; many windows were broken, 
and many brick chimneys and buildings were shaken down. The bricks of a chimney 
from a building about 30 feet high were thrown southward about 70 feet. Generally the 
chimneys seemed to have shifted or fallen southward, but in some cases they have tended 
to go in other directions. Many telephone wires were broken. In most cases water was 
spilt from water-tanks on all sides. It is reported that the water of several streams was 
partially thrown upon the banks. No cracks in the earth’s surface have been reported. 
