Leaving the region of the hills and descending from
their crescent-shaped expanse, we find a broad extent
of low ground, sloping gently toward the bay.
On this low-lying flat was built all of San Francisco’s
business houses, all its principal hotels and a large
part of its tenements and poorer dwellings. It
was here that the earthquake was felt most severely
and that the fire started which laid waste the city.
Rarely has a city been built on such doubtful foundations.
The greater part of the low ground was a bay in 1849,
but it has since been filled in by the drifting sands
blown from the ocean side by the prevailing west winds
and by earth dumped into it. Much of this land
was “made ground.” Forty-niners still
alive say that when they first saw San Francisco the
waters of the bay came up to Montgomery Street.
The Palace Hotel was in Montgomery Street, and from
there to the ferry docks—a long walk for
any man—the water had been driven back by
a “filling-in” process.
This is the district that especially suffered, that
south of Market and east of Montgomery Streets.
Nearly all the large buildings in this section are
either built on piles driven into the sand and mud
or were raised upon wooden foundations. It is
on such ground as this that the costly Post Office
building was erected, despite the protests of nearly
the entire community, who asserted that the ground
was nothing but a filled-in bog.
In none of the earthquakes that San Francisco has
had was any serious damage except to houses in this
filled-in territory, and to houses built along the
line of some of the many streams which ran from the
hills down to the bay, and which were filled in as
the town grew—for instance, the Grand Opera
House was built over the bed of St. Anne’s Creek.
A bog, slough and marsh, known as the Pipeville Slough,
was the ground on which the City Hall was built, and
which was originally a burying ground. Sand from
the western shore had blown over and drifted into the
marsh and hardened its surface.
When the final grading scheme of the city was adopted
in 1853, and work went on, the water front of the
city was where Clay Street now is, between Montgomery
and Sansome Streets. The present level area of
San Francisco of about three thousand acres is an
average of nine feet above or below the natural surface
of the ground and the changes made necessitated the
transfer of 21,000,000 cubic yards from hills to hollows.
Houses to the number of thousands were raised or lowered,
street floors became subcellars or third stories and
the whole natural face of the ground was altered.
Through this infirm material all the pipes of the
water and sewer system of San Francisco in its business
districts and in most of the region south of Market
street were laid. When the earthquake came, the
filled-in ground shook like the jelly it is. The
only firm and rigid material in its millions of cubic
yards of surface area and depth were the iron pipes.
Naturally they broke, as they would not bend, and San
Francisco’s water system was therefore instantly
disabled, with the result that the fire became complete
master of the situation and raged uncontrolled for
three days and nights.
