BEHAVIOR OF INDIVIDUAL STRUCTURES. 35 
CHRONICLE BUILDINGS. 
The Chronicle buildings, corner of Market and Kearney streets, 
comprised an old ten-story structure and a new fifteen-story annex 
that was in process of construction, both shown in PL XXX, B. The 
old building consisted of steel beams and protected cast-iron columns, 
with self-supporting walls, which had a brownstone front up to the 
second story and were ornamented with terra cotta above. The 
floor Avas of hollow tile, filled with cinder concrete and covered with 
wood. The cast-iron columns were fireproofed with 3-inch hollow 
tile, and 4-inch hollow tile was used for the partitions. The terra- 
cotta partitions and fireproofing entirely collapsed. The building 
appeared to have stood the earthquake shock, and received its prin- 
cipal damage through the fire. The collapse of the western section 
of the building was probably due to the buckling of the cast-iron 
columns. 
In the annex terra-cotta hollow tile was used for the floor con- 
struction, 4-inch hollow tile for the partitions, and 3-inch hollow 
tile for fireproofing the columns and girders. The curtain walls 
were built of sandstone, with terra-cotta trimmings for the front 
walls of the first and second stories, and brick and terra cotta for 
the remainder. The building was racked considerably by the earth- 
quake, the front walls developing the characteristic X cracks (a 
number of which may be perceived by a close inspection of PL 
XXX, Z?), due to a lack of diagonal bracing of the steel skeleton. 
The tiling failed extensively, the lower webs spalling off and the 
columns buckling in the southwest corner on the upper floors above 
the roof of the old Chronicle Building. There was little combustible 
material in the building, and the trim had not started; a few of the 
wooden window frames only burned; so that the fire test was not 
great. 
CITY HALL AND HALL OF RECORDS. 
The city hall (PL XXXI) was a brick building, at City Hall 
avenue, Larkin street, and McAllister street, consisting of steel floor 
beams and corrugated-iron arches with cinder-concrete filling. It 
was wrecked by the earthquake and subsequently gutted by the fire. 
A prominent feature was a central tower, surmounted by a dome 
built over a structural steel skeleton. Grouped around the dome 
were a number of cast-iron columns of half-inch metal filled with 
brick concrete supported on brackets. Some of these columns in 
falling broke into small pieces. The brickwork was completely 
shaken from the central tower. The cement-plastered brick walls 
were laid in lime mortar of generally poor quality and without 
adequate tie to the steel work. In some places there was an absence 
