BEHAVIOR OF INDIVIDUAL STRUCTURES. 41 
merchants' exchange building. 
The recently constructed modern office building known as the 
Merchants' Exchange, on California street between Montgomery and 
Sansome streets, caught fire from the outside and its contents were 
destroyed. The edifice was 13 stories in height, with steel skeleton, 
fireproof ed with plastered wire lath and reenforced-concrete floors. 
The floors of the rooms were of Avood ; the corridors Avere floored and 
wainscoted with marble. The fireproofing of the columns consisted 
of two layers of quarter-inch wire lath with a dead air space between, 
except those which AA T ere bricked into the outside walls. The sus- 
pended ceilings and partitions Avere likeAvise of plastered Avire lath, 
and the same material formed the Avails of the " fireproof " vaults. 
The curtain walls were of brick on the sides and rear; on the front 
the first two stories were of granite, the remainder being pressed 
terra cotta with terra-cotta trimmings. The heat of the fire Avas 
sufficient to calcine a large- portion of the Avainscoting and the marble 
treads of the cast-iron stairways. Though not completely destroy- 
ing it, the fire burned the life out of the plaster, all of which Avill 
have to be reneAved. The rear AA T alls Avere cracked by the earthquake. 
The enameled brickAA T ork of the light well (PI. XL, A) also shows 
earthquake cracks, and is badly spalled by the fire. The stonework 
was slightly spalled by the heat. The metal frames betAA T een the 
AvindoAA T s opening into the court AA T ere buckled, the cinder-concrete 
fireproofing being insufficient. The terra-cotta trim in the light Avell 
was also badly spalled. 
MILLS BUILDING. 
The eleven-story Mills Building, at the northeast corner of Bush 
and Montgomery streets, had a steel skeleton with hollow-tile fire- 
proofing and holloAA T -tile partitions. The floors AA 7 ere also of 1io11oaa t 
tile topped Avith cinder concrete and covered with Avood in the offices ; 
the tiling and Avainscoting of the corridors were of marble. 
The Avails were racked by the earthquake. The hollow tile failed 
and left the steel skeleton exposed to the fire. Just Iioav seriously 
it Avas damaged is problematical; four of the basement columns 
buckled (PL XL, />), the lower webs of the floor tiles failed over 
large areas (PI. XLV, B), and the partitions and the marble treads 
of the cast-iron stairways Avere destroyed. In the light well the 
AvindoAv casings were distorted by heat because of insufficient fire- 
proofing, and the terra cotta, granite, and exterior trim of the Avail 
were badly spalled. Owing to the failure of the floor tile many 
safes fell through the seA r eral floors. The building should be rebuilt. 
