ISOSEISMALS: DISTRIBUTION OF APPARENT INTENSITY. 179 
machinery — steam-engines, etc. — was not affected in the least. A high wind-mill and 
water-tank, 0.25 mile southeast, were unaffected. I am convinced that the shock was 
comparatively slight here, owing to the solid rock formation underlying. Had it been as 
severe as at Manchester (3 miles distant), or Point Arena (4 miles distant), both tower and 
dwelling would have been thrown into ruins. 
In Point Arena all brick buildings were thrown to the ground. Main Street runs north 
and south; all stores and business buildings (wood) on the east side of the street remained 
comparatively stationary, but all windows facing west in same were smashed, even the sash 
being thrown into fragments. Interior damage was great. Buildings on the opposite 
(west) side of the street and facing east suffered no breakage of windows, but nearly all 
moved west from a few inches to 2 feet. All chimneys were thrown east. 











————— d ee ae 
WW) \N es cs 
‘ \ \ \ \ 
\ N — 
\\ \\\ 
} ‘SY i" 2 ~~ 
) We bul \ ws \ se 

ai = 

ag 2a —s 
Fic. 49.— Cracks in light-house tower, Point Arena. - 
Buildings lower down on the slope as a rule suffered more, tho several wooden buildings 
high up, with underlying rock formations, were also wrecked. Nearly all buildings thruout 
the town moved west or northwest. In many cases houses drifted away and left porches 
standing in their old location. On the creek-bottoms many small cracks or fissures appear, 
thru which fine slate-colored sand has been forced to the surface, forming cones. 
Between Point Arena and Gualala there are few dwellings and little of a definite nature 
could be ascertained by Mr. Matthes in his examination of that section. 
At Fishrock, population 75, Mr. James F. McNamee estimates the damage at $1,000. 
The town is on a terrace of the coast 150 feet above sea-level on rocky ground. 
Gualala, Mendocino County. —'The wagon bridge over the Gualala River, south of 
the town, was seriously damaged. It consists of a trussed three-span structure 500 feet 
long, with a wooden approach of similar length built on trestles 20 feet high thru the 
swampy bottom-lands on the south side. This approach collapsed completely, the 
trestles being thrown flat and carrying with them the south end of the main span. The 
latter, however, did not leave its northern abutments and appears otherwise undamaged. 
It is considered safe to travel over, altho the bridge floor is now steeply inclined to the 
south. (See plate 68c.) In the town, population 75, all chimneys broke off; plaster 
cracked in the hotel and several other buildings; a few small dwellings were thrown off 
their underpinnings. Household articles and furniture suffered severely, most of the 
crockery and glassware in the town being destroyed. 
