coast defense

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Fire Control, Radio, and Searchlight

There are five fairly unusual fire control structures (FCSs) at Fort Andrews, four of which pre-dated WW2. The fort also had its own radio station, and featured an uncommon disappearing coastal searchlight.

The first FCS [see Slides 3 and 4] was the elegant old two-story brick tower built in 1904 on the east side of the tall ridge on the northern end of the island [here called the "east side station"]. Originally the FCS held base end/spotting stations for Bttys Rice and McCook, as well as the Fort Commander's station. Later, it was designated the Battery Commander's station for Btty McCook alone (after Btty Rice did not receive any guns).

Next came the large (32' x 40') fire control building atop the 120-foot hill on the west side of the fort. Constructed in 1907, this structure [see Slides 15-17] housed twin DPF instruments and plotting rooms for the 16 mortars of Batteries Whitman and Cushing. The building was originally built at the bottom of a pit about 12 ft. deep, placing the axis of observation for the instruments only a few feet above ground level. Today, the building has been collapsed in upon itself by fallen trees and has slowly been deteriorating, choked with debris and vegitation so it can not easily be explored.

This building, which seems to have been abandoned before WW2 (the mortar batteries it supported were discontinued in December, 1942) was accompanied by a 16-foot square dormitory and a 16' x 10' latrine constructed behind it, but nothing remains of these outbuildings except some vine-covered concrete foundations about 50 ft. to its west.

Then, in 1925, two more fire control positions were built. One, a coincidence range finder (CRF) station [see Slides 1 and 2] for the 3-inch guns of Battery Bumpus, was located in a pillbox-like bunker built over the platform originally intended for Gun 1 of Btty Rice, at the other (westerly) end of the row of gun positions on the north end of the island. The other, a Depression Position Finder (DPF) station for Btty McCook [see Slides 5-7], was set up in a 6'6"-cube pillbox-like bunker that was mostly buried, about 70 feet in from the lip of the bluff northwest of Btty Rice [the distance from the lip had shrunk to about 30 feet by 2010, due to erosion]. Both of these positions were part of the WW2 fire control system at the fort. [[Slide 7 shows the gaping entry shaft to the DPF bunker hidden in the brush, a real hazard to a careless visitor.]

The final position was a base end/spotting station constructed in 1944 (surprisingly late in the war) for the 6-inch guns of Battery McCook [see Slides 10-14] and located up on the western hill about 50 ft. south of the 1907 Whitman-Cushing station mentioned above.

Unique among other Boston coast artillery installations, Ft. Andrews was provided in 1909 with its own radio transmitting station, a 16' x 22' structure with a radio room, a work room, and a generator room (although the generator seems to have been rated at only .36KW). The radio station building could not be found in the thick underbrush during a recent (2010) field visit.

The fort's searchlight emplacement (see the lower gallery at left) is located about 30 ft. behind the McCook DPF pillbox. As the photos [Slides 1 and 2] show, what is visible today is the heavily rotted rail-mounted wooden cover for the pit into which the 60-inch searchlight of 1924 [Slide 3] was designed to be lowered. The cover would be slid back along the rails, and two men would operate a hoist which would lift the light from its concrete pit. That pit was about 9 x 19' and 14' deep. [Today one must be very careful in exploring near the searchlight pit, since it would be easy to fall down its access shaft or fall through its rotted cover.

The 60-inch light installed in 1924 included a GE N-6 projector, which replaced a 36-inch GE EC-36 unit that had been installed in 1914. The smaller light had apparently been mounted in a surface shelter close to (or at) the location of the 1924 pit. An N-10 unit replaced the N-6 light in 1942. These successive lights were each controlled by remote cable from the 3-story east side fire control station, and drew their power from one of the two 25KW generators at Btty Cushing, about 1200 ft. distant.

The 60-inch searchlight is said to have had an effective range of 5 or 6 miles, which would make it possible for the Ft. Andrews light to cover the entire mouth of the harbor between Hull and Ft. Dawes (Deer Island), reaching westward all the way to Boston (over a few islands) and northeasterly well out past the Brewsters.

Fire Control and Radio

  • Bty Bumpus BC And CRF-2
    This unusual fire control station was built atop the platform for Gun 1 of the never-used Bty Rice. The photo looks almost due west, so the pillbox is oriented towards the north. It is described as having had a 9-foot coincidence range finder (CRF) inside, and since the station itself is only 13 feet square, it must have been a tight fit. (PG 2010)
  • Interior Of Bumpus BC And CRF
    Photo looks westerly across the interior of the 13-foot square pillbox. The mounting pad for the CRF is seen at lower right. The remains of four or more communications circuits run down the western wall, just out of view here. (PG 2010)
  • East Side Station-Rear
    Photo looks northeasterly at this 2-story fire control station. It had brick walls with a concrete roof and armored steel doors. Upstairs was an observation room with two spotting scopes and a DPF, plus a plotting room. Downstairs were three smaller rooms. An old-style concrete pillar for the DPF ran up through the building to the second floor. The interior has been secured against vandalism. (PG 2010)
  • East Side Station-Front
    The building, which commands a panorama of Boston's outer harbor, is oriented about 20 deg east of north. When the bluff was completely bare of vegetation, however, it would have stuck out like a sore thumb, able to be targeted from quite a distance. (PG 2010)
  • McCook DPF
    Photo looks southerly at the front of the partially buried bunker. There are two steel shutters over the observation slit; the right one is open, the left closed. This photo was taken in early April, or the thorny vines would likely have made the bunker invisible. The searchlight pit is about 30 ft. SW of this bunker, out of this photo to the right rear. (PG 2010)
  • McCook DPF Detail
    This image more clearly shows the shutters on the observation slit. A geodetic marker (MY4556) is reportedly set "in the roof" of the pillbox, but an hour of digging could not find it. The roof is concave and packed with more than 10" of rocks and dirt. (PG 2010)
  • McCook DPF Access Hatch
    This photo looks back northerly towards the channel. Ft Warren would be visible if the bluff were not overgrown (see Slides 8 and 9 for views). The hatch is in the left rear of the bunker and has iron ladder rungs running down its side. Top of bunker is completely covered with soil and undergrowth, and shaft is clearly a danger to anyone not watching their step. (PG 2010)
  • Ft Warren From McCook DPF
    This photo, looking north from the lip of the bluff (beyond present day undergrowth) shows the view of Ft. Warren (on George's Island) that would have greeted observers in the McCook DPF pillbox during WW2. Water in the foreground is the channel to Quincy Bay, the Fore River Shipyard, and the southern approaches to Boston, past what is now the causeway to Long Island. (PG 2010)
  • Fts Strong And Dawes From McCook DPF
    This view looks slightly more to the NNW than Slide 8 and shows Ft. Strong to the left and Ft. Dawes (now the huge MWRA sewage treatment plant) to the right. A ship entering the channel to either side of Ft. Strong would have come under concentrated fire from 3-inch and 90 mm guns of these forts and several others, including the 6-inch and 3-inch guns of Ft. Andrews. (PG 2010)
  • B 1-4 S 1-4 Looking W
    Photo looks west at the east corner of the bunker. The door is located in the NW face. (PG 2010)
  • 1944 FC Bunker-Windows
    Some of the original wooden and glass windows on the observation slit of the bunker, which look like they were installed only a few years ago. Finding a feature like this that has not been vandalized over the past 70 years is a rare occurance, likely abetted by the out-of-the-way location of the bunker. Heavy undergrowth makes it invisible until you're almost upon it, and it would be hard to find without a GPS fix on the geodetic mark within it. (PG 2010)
  • View Frm 1944 FC Bunker
    Seventy years of uncontrolled forest growth have somewhat reduced the usefulness of the bunker as a fire control point. This photo looks northeast toward Outer Brewster Island, which was likely visible in 1944. (PG 2010)
  • 1944 Bunker-Light And Wires
    Time (and the completion of field work on the harbor defenses) will tell, but this glass globe for the light over the center of the bunker might be the last of its kind in the Boston harbor defenses. Dangling communications wires were likely attached to headset jacks on a mounting board next to the light.
  • MY0020-RM3 Under Instrument Base-N
    This arrangement is likely unique. The bunker (and more precisely the center of its octagonal instrument base) was built on top of a geodetic mark (Reference Mark #3 for nearby station ANDREWS--MY0020), and an access hatch was left so that the crawlspace with the mark could be reached. (PG 2010)
  • 1907 FC Bldg, Destroyed
    Photo looks east across the 15-foot-deep excavation which held the 1907 fire control building. This structure, about 50 ft. north of the 1944 bunker, has been caved-in by fallen trees. The concrete pillar which used to support one of two Depression Range Finders (DPFs) is at center right, beneath the tree branch. The building used to have a built-up gallery on its east side, from which observers could use the instruments, but this has now been collapsed onto the lower level, which held plotting rooms for the two mortar batteries. The more northerly end of the building, out of the image to the left, has a second DPF pillar, and is even more seriously battered and heavily overgrown. (PG 2010)
  • 1907 FC Bldg Window
    This window, visible at the right of the photo in Slide 15, still contains some panes of 1/4"-thick glass with wire mesh embedded in them, probably meant to protect against showering glass splinters in the event of bombardment. (PG 2010)
  • 1907 Bldg--Construction Detail
    No other example of these wood-and-stucco buildings is known to exist within the Boston harbor defenses, since they have generally all been demolished over the past 95 years. This photo looks toward the SE corner of the building along a wall that has been pushed out from the inside. Both the inner and outer coat of rough plaster or stucco are visible, along with the steel mesh that held them. Photo is taken from the opening for a window that has been knocked out. (PG 2010)