50 THE SAN FRANCISCO EARTHQUAKE AND FIRE. 
in the business district: (1) Bad exposures and unprotected open- 
ings; (2) poor construction ; (3) an absence of sprinklers or of any 
of the modern protective devices; and (4) excessive height in non- 
fireproof structures. It is stated that in the congested district about 
2.2 per cent were fireproof, 68.3 per cent were wooden joisted brick, 
and 29.5 per cent were frame buildings. A very bad feature lay in 
the fact that a large number of so-called " fireproofs " were sur- 
rounded by nonfireproofs. The mixture of dwellings and minor 
mercantile buildings surrounding the congested-value district also 
greatly increased the hazard. 
The board recommended the municipal ownership of the water sup- 
ply. They considered the present supply ample in amount for the 
existing requirements, but subject to a decided probability of local 
failure in emergencies, owing to faults in the distribution system. 
They deemed it very desirable to increase the capacity of the existing 
system and to install at the earliest possible date a separate fire-main 
system, and recommended that all dead ends of pipe mains be con- 
nected with the network wherever practicable. They advised that 
the system of distribution be equipped with a sufficient number of 
gate valves, so located that no single case of accident, breakage, or 
repair to the pipe system would necessitate the shutting from service 
of a length of main greater than the side of a single block (a maxi- 
mum of 500 feet) in important mercantile manufacturing districts, 
or than two sides of a single block (a maximum of 800 feet) in other 
districts. 
The building code was found to be satisfactory on the whole, but 
the board recommended that it be so amended as to limit floor areas, 
provide for the protection of exposed openings in fireproof build- 
ings, and encourage the use of modern protective devices and construc- 
tions, such as sprinkler equipments, automatic fire doors, wire glass, 
etc. They recommended that prompt measures be taken to relieve 
the hazardous conditions in narrow streets by widening the streets 
or enforcing adequate window protection, or both, and advised that 
automatic sprinkler equipments be required in all buildings which by 
reason of their size, construction, or occupancy, singly or combined, 
might act as conflagration breeders. The potential hazard was con- 
sidered very severe, in view of the exceptionally large areas and 
great heights of many buildings and of their highly combustible 
nature by reason of sheathed walls and ceilings, numerous ui '.pro- 
tected openings and light Avells, and the general absence of fire 
breaks, taken in conjunction with the presence of interposed frame 
buildings and the comparatively narrow streets. These numerous 
and mutually aggravating conflagration breeders, considered in con- 
nection with the almost total lack of sprinklers and gen&ral absence 
