86 THE SAN FRANCISCO EARTHQUAKE AND FIRE. 
were stretched beyond their elastic limit. I found, on personal exam- 
ination in the field, that many of the wind struts had almost slipped 
from their seats on the columns. The bolt holes or rivet holes in- 
tended for bolts or rivets to hold the struts in place between their 
seats were not filled. Whether this was due to the fact that they had 
been sheared by the earthquake or whether they had been omitted in 
erection, I could not determine definitely. The latter will seem a 
plausible supposition to anyone familiar with the way in which the 
average erecting gang does its work. A few of the wind struts had 
absolutely slipped from their seats and fallen down; but it was not 
possible to determine from the visible evidence whether this damage 
was due to the earthquake or to the precipitation of the mass of 
masonry upon the struts as a result of the failure of the outer walls. 
Examination of the diagonal tie-rods made it apparent that some 
of them may have been stretched and bent by the mass of masonry 
falling upon them, but that others had very clearly been stretched 
beyond the elastic limit by the vibration of the tower during the 
earthquake. In inspecting the inside of the rotunda I observed con- 
siderable earthquake damage to the tower, including the stretching 
of a pair of diagonal tie-rods in the dome by the impact of the 
falling material. The terra-cotta floor at the base of the dome was 
absolutely intact, so far as could be determined. I made an effort 
to get out upon the steel work of the tower to climb it, but could 
only get as high as the gallery in the rotunda on a level with the 
upper floor of the main building. The means of access to the higher 
points had been evidently destroyed by the earthquake. The portion 
of the tower above this point, however, was carefully examined 
through a very good field glass, which enabled me to see a great many 
details practically as well as if I had been able to climb the tower 
itself. Among other things, it indicated very clearly that this terra- 
cotta floor was of a much better type than those ordinarily put into 
commercial buildings. 
Around a portion of the rotunda there was an inner wall, built of 
hollow tiles, which the earthquake had so shattered that practically 
the entire Avail would have to be taken down in order to make ade- 
quate repair. It will be noted by an examination of PI. XXXI that 
the brickwork of the building fell and broke up into large masses. 
If it had been very poor brickwork it would have broken up, for the 
most part, into individual bricks, and the fact that it did not do so 
is proof that it was not of a kind to call for serious censure of the 
architect or contractor. There was practically no fire in the*rotunda 
of the tower of the city hall. Opposite the main corridor connecting 
with the portion of the building to the north the varnish on the 
hand rail in the upper galleries was scorched, but on the main floor 
