RECOMMENDATIONS IN RELATION TO CONSTRUCTION. 125 
edly saved the masonry. In such buildings as the new Chronicle 
and the Monadnock the effect of the vibration was really resisted by 
the masonry, which was much shattered. Some of it was precipitated 
into the street from the new Chronicle Building, the Rialto Building, 
and others. It is not at all certain that the steel frames of these 
buildings have not also been seriously damaged by the earthquake. 
Naked steel frames of the same type came through without serious 
damage, but they did not suffer the additional stresses due to the 
vibration of a great load of masonry, floor construction, and con- 
tents in the upper stories, as did the finished buildings. It is not 
right to run the risk of precipitating the masonry into the street on 
the heads of passers-by, as would have happened at the unbraced 
steel-frame buildings had the earthquake occurred at a later hour in 
the day. Besides, if the strength of the building is dependent on the 
masonry, which is seriously shattered by the stresses that it is 
expected to resist, the factor of safety against general collapse is 
manifestly too small. The steel-frame construction should therefore 
be thoroughly braced. In my judgment, to obtain the best results it 
should also be inclosed with walls of reenforced concrete, in which 
case it would be almost impossible to throw the walls off. The proper 
artistic treatment of this material in a place like San Francisco would 
seem to be a very important problem for the architects. The great 
utility of reenforced concrete in earthquake shocks can not be denied. 
Where steel-frame buildings are to be finished with ordinary masonry 
w r alls, however, complete bonding of all face bricks with full header 
courses should be absolutely required. No other form of bond is 
adequate. Nothing but Portland-cement mortar should be allowed in 
any part of the structure. The masonry should be tied to the steel 
frame in the very best possible way, and much more securely than is 
ordinarily the case. 
For buildings of moderate height, say up to 125 feet as an extreme 
limit, reenforced concrete alone can undoubtedly be so designed as to 
give very good results when subjected to either earthquake or fire. 
But the bracing of a reenforced-concrete building of any height to 
resist earthquake is a matter for serious study. The problem can be 
solved, but it has not been solved yet. 
Any building of considerable height, in an earthquake country, 
should have as little mass in the superstructure as possible, consistent 
with other necessary qualities. But this limiting of mass does not 
mean that the flimsy floors and partitions heretofore in use should be 
continued. In fact, to make the buildings proof against both earth- 
quake and fire it is probable that they will have to be at least as 
heavy as they have been, but changes in distribution of the mass 
could advantageously be made. 
