Kona Earthquake — MACDONALD AND WENTWORTH 
275 
period of about 14 minutes, reaching an 
amplitude from crest to trough of 3.6 inches. 
This undoubtedly is the record of a seiche 
set up in Honolulu harbor by the tsunami. 
Using the time of beginning of the disturb- 
ance at Honolulu as that of arrival of the 
tsunami, the average speed of travel of the 
tsunami from the epicenter to Honolulu was 
approximately 284 miles an hour. The time 
of beginning of the disturbance at Honolulu 
corresponds well with the calculated theo- 
retical arrival time of a tsunami caused by 
the Kona earthquake, so there can be little 
doubt the disturbance was of that origin. A 
similar disturbance is shown on the record 
of the Hilo tide gauge. The time of beginning 
of the disturbance at Hilo is less definite, but 
appears to have been about 02:38. This cor- 
responds with a much slower average speed 
of travel of the tsunami, of about 78 miles 
an hour, as the waves were refracted around 
the island in comparatively shallow water. 
Damage to Buildings 
Shortly after the earthquake the Kona po- 
lice estimated that about 200 houses in the 
area had suffered some degree of damage. 
Most houses in the area near the epicenter 
are of frame construction, set on knee-braced 
timber underpinning. Such supports proved 
capable of undergoing the shaking and dis- 
tortion caused by the earthquake without 
serious damage. Most of the damage was 
minor and quickly repaired. Some houses 
shifted from a fraction of an inch to 3 or 4 
inches on their foundations. Many were suf- 
ficiently twisted out of line to make it dif- 
ficult or impossible to close windows and 
doors. In nearly all houses dishes and other 
objects were thrown from shelves. Only the 
more seriously damaged structures are enum- 
erated here. 
At Kaimalino, 0.3 mile south of Kealia 
(Fig. 1), a shop building collapsed. This build- 
ing was placed on timber supports level with 
the highway in front but 6 feet above ground 
level in back, without adequate cross bracing. 
Fig. 4. Overthrown shop building at Kaimalino, 
from the south. 
Failure of the underpinning allowed the 
building to tilt backward and slump to the 
ground (Fig. 4). A similar situation was found 
at Keokea, 1.2 miles north of Kealia, where 
a service station building slumped downhill 
away from the highway and partly collapsed. 
In the Kahauloa area, about 1.7 miles east 
of Napoopoo village, the walls of a store 
partly collapsed as a result of distortion of 
the building caused by shifting on its founda- 
tion. The warehouse of another store was 
badly damaged. 
At Hookena Beach two old frame houses 
were destroyed. One, which had been oc- 
cupied briefly in 1889 by Robert Louis Steven- 
son, fell when its timber underpinning failed, 
and collapsed. The other also was dropped 
onto the ground by collapse of its under- 
pinning. It appears to have fallen almost 
straight downward. The building was some- 
what twisted, but not otherwise seriously 
damaged. At Kealia and at Kiilae, about 0.4 
mile south of Kealia, two other frame houses 
were badly damaged by collapse of their 
timber underpinning. All of these cases of 
collapse of frame houses appear to have been 
caused by inadequate bracing or poor mate- 
rials in the underpinning, in some instances 
probably aggravated by insecure footings. 
The cases of structural damage most dis- 
tant from the epicenter occurred at Naalehu, 
36 miles southeast of Napoopoo, where wall- 
board in a restaurant was cracked, and one 
