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The Doyle Drive Historic Corridor

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     View North from Battery Baldwin toward U.S. Coast Guard Station

Looking north from Battery Baldwin toward the U.S. Coast Guard Life Saving Station (today the Gulf of the Farallones National Marine Sanctuary Visitor Center) and San Francisco Bay, ca. 1905–1910. Courtesy Golden Gate National Recreation Area, Park Archives (Presidio Army Museum Collection, GOGA 35245.0611)

BEGINNING AROUND THE TIME OF THE SPANISH-AMERICAN WAR of 1898, the Army constructed four coastal defense batteries along the bluff north of the San Francisco National Cemetery: Batteries Slaughter, Sherwood, Blaney, and Baldwin. They were products of the “Endicott Era” of coastal defense improvements that specified poured concrete batteries instead of brick forts or earthen batteries, and the development of larger, more powerful, and more accurate weaponry. Armaments included 8- 10- and 12-inch caliber guns often mounted on “disappearing” carriages that allowed guns to remain invisible to battleships while being loaded and serviced.

BATTERY SLAUGHTER WAS THE FIRST AND LARGEST BATTERY built on the bluff. It included two magazines and three emplacements armed with 8-inch guns mounted on disappearing carriages. Battery Sherwood, built for two 5-inch non-disappearing rapid-fire guns on pedestal mounts, was completed in 1901. Battery Baldwin was completed in the same year. Battery Blaney was completed in 1902. Eventually, Battery Baldwin was armed with two 3-inch rapid-fire guns on pillar mounts and Battery Blaney with four 3-inch guns.

Map of Fort Scott and Presidio of San Francisco, California, 1918

Map of Fort Scott and Presidio of San Francisco, California, 1918 (annotated). Courtesy Golden Gate National Recreation Area, Park Archives (D311F2).

ADVANCES IN HARBOR DEFENSE TACTICS made these batteries and guns obsolete and they were disarmed by 1920. With the construction of the Golden Gate Bridge, Battery Baldwin and portions of Battery Slaughter were either partially demolished or buried to make way for Doyle Drive.

IN 1905, NEW IMPROVEMENTS TO SAN FRANCISCO’S COASTAL DEFENSES focused on artillery targeting or “fire control.” The Coast Artillery Corps replaced direct sighting of targets with a new, more accurate, and more complex “base end” targeting system that required multiple sighting or base end stations and rapid transmission and processing of target data.

Coastal artillery plotting room, 1942.

Coastal artillery plotting room, 1942. The Coastal Artillery Corpsmen pictured here are performing the kinds of targeting calculations which earlier Corpsmen would have performed within the plotting rooms of batteries armed with larger guns (8-inch or more) such as Battery Slaughter. San Francisco History Center, San Francisco Public Library

BUILT IN 1909 BETWEEN BATTERY BALDWIN AND THE CAVALRY STABLES, Switchboard Room No. 3 was the communications hub for the batteries. Telephone cables reached from Fort Winfield Scott in the western part of the Presidio through the lower level of Switchboard Room No. 3 and continued to the Presidio’s Main Post. Branch telephone lines extended the main line north to the batteries and to Fort Winfield Scott’s Ninth Command fire control station built in 1909. A critical part of the coastal artillery system, this telecommunications technology allowed the Army to implement the new base end targeting system.


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