56 THE SAN FRANCISCO EARTHQUAKE AND EIRE. 
4. The use of explosives, such as dynamite, for fighting a fire 
should be greatly restricted and intrusted to experts only, or else 
abandoned. It is extremely doubtful whether the progress of a fire 
can be checked by dynamiting in advance of the fire without the 
removal or thorough wetting of the debris. Such procedure would 
have been impossible in San Francisco, as the water supply ivas 
unavailable and it was impossible to carry away the wreckage. The 
indiscriminate dynamiting did more harm than good, for the reason 
that the concussions injured the surrounding buildings, as shown, for 
example, by the extensive damage done at the post-office. Back firing 
would have been equally bad, because to apply this method success- 
fully plenty of water for controlling the fire is necessary. A fire 
stop is the best way of checking a conflagration, and a fireproof 
structure makes the best fire stop if it has well-protected openings. 
GENERAL LESSORS OF THE EARTHQUAKE AND FIRE. 
In considering the results of the destruction which was wrought by 
the earthquake and fire there appear certain salient features from 
which conclusions may be drawn. In regard to the possibility of the 
erection of an earthquake-proof structure, it is apparent and univer- 
sally admitted that it would be impossible to build on the fault line 
a structure which could withstand the effect of a slip. Furthermore, 
it is realized that in building near the fault on soft or alluvial soil 
extra precautions must be taken; for example, location of the San 
Francisco water mains in ground of this character Avas unwise, since 
it is difficult to design a waterworks system capable of resisting the 
effect of settling of the ground. The importance of proper construc- 
tion and distribution of the water mains in districts liable to earth- 
quakes is demonstrated by the fact that the greatest damage in San 
Francisco, fully 85 per cent of the total, was by fire. The action of 
the earthquake in starting the fires which grew to a great conflagra- 
tion seems insignificant compared to the breaking of the water mains, 
which left the city defenseless against the flames. 
The comparatively great destruction wrought by the earthquake 
to structures located on filled ground or alluvial soil has already been 
pointed out. The destruction in San Francisco was confined largely 
to buildings located on the alluvium of the flats or on the filled 
ground of old watercourses. That structures can be built, however, 
which will satisfactorily meet even such conditions when adequate 
foundations are provided, extending through the soft material to a 
solid base, is demonstrated by the behavior of such buildings as the 
Leland Stanford Junior Museum (PI. XIV, A) and Eoble Hall, at 
Stanford University; the Government buildings (Pis. XXVIII, A ; 
XXXVIII; XLII, B; XLIII; XLIV), and the Call and other 
buildings in San Francisco. 
