BEHAVIOR OF INDIVIDUAL STRUCTURES. 81 
tinuous over the top of the beam ; otherwise the construction is noth- 
ing but an arch, and develops the thrust to be expected of an arch. 
Moreover, as a rule, tie-rods are omitted when reenforced-concrete 
floor slabs are used, and it was naturally to be expected that reen- 
forced-concrete floor slabs of this type would collapse to some extent ; 
the wonder is that they did not collapse to a greater extent in the 
Bullock & Jones Building. The fire damage to ornamental terra 
cotta in this building w T as very conspicuous. 
CALL BUILDING. 
Of all the commercial buildings in San Francisco, by far the most 
interesting was that known as the Call (or Spreckels) Building, at 
the corner of Third and Market streets. This building is remarkable 
for the care and skill shown in the design of its steel work. It is a 
steel-frame building, all the walls, floors, partitions, etc., being car- 
ried on steel work. It has 15 main stories, in addition to the stories 
in the dome, or cupola, and rests upon a continuous foundation com- 
posed of concrete reenforced with steel beams. The building proper 
is about 75 feet square, but the foundation is about 90 by 110 feet, 
and was carried to a depth of about 25 feet below the sidewalk level. 
A fairly complete and satisfactory description of this building was 
published in the Engineering Record of April 9 and 16, 1898. 
In the first four stories above the street the bents of the steel work 
adjacent to the four corners of the building on each side were braced 
with solid portal braces. In addition, eight interior bents were 
braced with diagonal debars from top to bottom. At all junctions 
of girders and beams with columns knee braces were used. The de- 
sign of this steel w r ork is well worthy of study by anyone interested in 
such structures. It is probably, on the whole, the best-designed 
piece of such work in the United States. Another remarkable thing 
about it is that the execution was apparently as good as the design. 
In a number of places wdiere the fireproofing had come off the connec- 
tions were exposed, and the workmanship here seemed to have been 
practically as good as it could well be made. I particularly noticed 
the column bearings, and they seemed to be absolutely close and true. 
Inaccurate column bearings in building work are so often seen that 
one is almost justified in saying that they are the rule rather than 
the exception; but in the Call Building such connections as were 
exposed to view had been put together with extreme accuracy. 
The column covering in this building was of hollow tiles, about 3 
inches thick, with very thin webs. Partitions were built of the same 
material. The floor construction was of reenforced cinder concrete. 
Some furred ceilings composed of wire lathing and light furring 
strips were also used. The outer walls were furred with 2-inch 
