BEHAVIOR OF INDIVIDUAL STRUCTURES. 99 
more important rooms had a great deal of expensive and beautiful 
marble finish; there was much marble-mosaic ceiling work, and the 
finished woodwork was of extraordinary richness. On top of the 
buildings were a number of chimneys built of granite blocks with 
terra-cotta linings. 
All the materials entering into the construction and finish of this 
building were the best of their kind, and the workmanship, under 
the efficient supervision of Mr. Roberts, was as nearly perfect as it is 
possible to make it. I have never, seen work better done, and have 
rarely seen it so well done. To one who knows and appreciates good 
work it is a continual pleasure to see everywhere in the San Fran- 
cisco post-office the record of sleepless vigilance and skilled labor. 
Where the structural parts were laid bare by the damage due to the 
earthquake, the same story was told by the minutest details as well 
as the roughest parts of the work — everything was the best of its 
kind. It is therefore of great interest to study the effect of the 
earthquake on this structure, for the care with which it was built 
must have made it fully as good as its designers could have hoped. 
Moreover, I am inclined to think that it received a more severe shak- 
ing than any other building in the congested district of San Fran- 
cisco that was at all comparable with it. The city hall was badly 
racked, but, to judge from the condition of the adjacent street sur- 
faces and the surrounding ruins, the shock was much less severe than 
that to which the post-office was subjected. For instance, there was 
a partially erected steel frame (PL XLII, B) on the southwest side 
of Seventh street, near the post-office. Before the earthquake all the 
columns were plumb and in true alignment. As a result of the shock 
there was a lateral shifting of the column bases — the relative move- 
ment being almost 2 feet in some places — at the cellar-floor level. 
The basement walls of the incomplete building were also shifted 
horizontally; at the east corner, where the walls had met at a right 
angle, they had been ruptured by a vertical crack and moved laterally 
in such a way that the angle between them was reduced to about 75°, 
as nearly as 1 could estimate it without taking measurements. 
The south corner of the post-office building is shown in PI. XLIV, 
A. Mr. Roberts states that accurate measurements show that the 
building proper settled a little at this point, but not more than one- 
eighth inch relative to other parts of the structure. The general 
appearance of the building bears out this statement. The result is 
remarkably gratifying when the great extent of the near-by surface 
disturbance on Mission street is considered. The street went down 
about 4 or 5 feet at this point as a result of the earthquake (PL 
XLIII, B). The molded granite shelf surrounding the building, 
shown with small timber props under it in PL XLIV. J. was set into 
a rebate in the main wall of the building. A\ nen the sidewalk and 
