Historic California Posts, Camps, Stations and Airfields
Fort Barry: Battery Mendell
 One of Battery Mendell's 12-inch rifles, circa 1938. Photograph courtesy of the San Francisco Public Library
Battery Mendell was the first of the batteries built at Fort Barry. Construction was started in July 1901 and was completed in 1902.
On 22 November 1902, War Department General Order 120 named the battery after Colonel George H. Mendell, Corps of Engineers. After his graduation from the United States Military Academy in 1852, Colonel Mendell began a long career in planning and designing military structures. During the late 19th century he had supervised a majority of the post-Civil War and early Endicott-type fortifications that protected San Francisco Bay. In 1902 Colonel Mendell died in San Francisco.
In 1905, two M1895A4 12-inch breech loading rifles (numbers 4 and 6) made by the Bethlehem Steel Company arrived on site. They were mounted on disappearing carriages (Model 1897, numbers 30 and 31) fabricated by the Midvale Steel Company. These guns fired a 1,100 pound projectile over eight miles.
These guns remained emplaced until 1943, when the threat of imminent invasion was over and more modern Battery Elmer J. Wallace was reactivated following that battery being casemated. The guns were removed and scrapped that same year.
For decades, the battery fell into disrepair and was a target for vandals. But today, thanks to the National Park Service, portions of the battery are being repaired and restored.
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 One of Battery Medell's two 12-inch rifles firing, 30 April 1941. Photograph courtesy of the San Francisco Public Library

How does a Disappearing Gun Disappear?
When a lever is pulled, a lead counterweight drops and the aimed barrel rises to the firing position. After the gun is fired, its recoil drops the gun below the parapet. This feature made the gun invisible to enemy ships and protected the crew during loading. But, while it was an effective weapon against ships, it had no protection from what its designer could not have foreseen, the airplane. Batteries designed after World War I were casemated, providing their crews a large degree of overhead protection. Below are some rare color photographs showing the battery's gun in action.
Technical Data
by Chuck Wofford
Battery Mendell was named in GO 120 dated November 22 1902, in honor of Col George H. Mendell, Corps of Engineers who had more to do with the defenses of San Francisco that any other engineer officer. He died in San Francisco in 1902. This was the first battery to be construction at Point Bonita.
This Endicott era battery had two B.L.R. 12-inch guns, model 1895, nos 4b, and 6 mounted in this battery. Gun # 4B was received July 10 1903 and gun # 6 was received Aug. 8 1904. There were 56.manufactured by the Bethlehem Steel Company.

These guns were mounted on disappearing carriages, model 1897, nos 30 and 31, with retracting motor, there were 35 built, Original Emplaced-35 Time of Emplacement: 1899-1904. They were mounted with 14 bolts inner, 14 inner, 12 outer, Circle Diameter: 14� 2" inner, 18' 4": outer, Parapet Height: 13' 11.5", Center to Parapet: 13' 5". There were 5 steps. Carriage # 31 was received July 14 1902, Carriage # 30 was received July 30 1902. They were manufactured by Midvale Steel Company.
The following is the information on the Model 1895 # 4b and 6
The following information is on Carriages Model 1897
Ammunition Service
The means, which must be provided for moving ammunition, depend of course upon the weight and bulk, a shell for this battery weighted 10000 lbs and a powder charges weighted 80 lbs. There was a trolley rails fastened to the ceilings over the center of gravity of the shells in each row, after 1908 this was changed, and the larger shells were stacked in two rows down the middle of the shell room, there fore there was a passageway between the walls and between the rows and then over the receiving tables of the hoists.

The form of a trolley used in a battery was a simple I beam attached to the ceiling by bolts thought an upper flange, this form consisted of a pair of wheels running on the lower flange on either side of the beam and held together by a U-shaped yoke hanging down under the beam, each trolley carried a half ton Yale-Weston triplex block. As to vertical movement of the shell, a new form of telescoping shell tongs an appliance for seizing hold of the shell, they used a tongs, which looked like a pair if ice tongs, except there were three rather they two, two on one side and one on the other, and was located to close between the two other tongs, then opened wide and placed as near the center of gravity as possible, then they are closed and ready to be moved, the Yale-Towne block and the Ordnance shell tongs are the standards used.
As far as Powder Service, the powder was shipped to the battery in metal cases and stored in racks, that they were shipped in, in most cases, there ends projecting into the passageway. When a cartridge was desired the solder strip was to be pulled of without moving the cartridge case from the rack, this loosens the top of the case and the cartridge is then pulled out, leaving the case still fastened in it proper place. All the powder is carried in a handbarrow, by four men, and is taken to the gun for loading.
The ammunition supply for this battery was stored in the shell room which there were 4, 2 were 12 X 45 X 8 and there were two this size and two were 11 X 22, the larger of the two were on the first floor behind the two guns of the battery, the other two were to the right of the powder room on the right side of the guns at the front of the battery, held over 240 shells each for gun. The size of the Powder Rooms 28'-6" X 22'-6" and one 25'-6" X 22'-6" and there were two of them both to the front of the battery to the Right of the guns, and next to the small Shell Room and held 264, for each gun. The battle allowance for this battery was 200 rounds of fire, the 200 projectiles we A.P. 870 LB MK xv1 bsco Navy modified under special work order 15 dated August 16 1935 (modification consisted of cutting groves in the rear of the rotating band and was completed January 1936) Larger amounts could be put in the shell and powder room by stacking higher and closer together. (In May 16 1913. it was stated that the shell room for emplacement # 2 could store 160 projectiles could be stored in the shot and shell room, but 120 more could be stored in the galleries, and in the service magazine 220 rounds could be stored, In a letter dated Aug. 1 1940, there was stored in the projectile 200 each A.P. 870 lb., and 200 charges in the powder room, and in emplacement #2, the same amount were stored).
The Sights for #2 emplacement was a new telescopic, 3-inch, Model 1904, which were received November 18 1907; Serial # 395. For emplacement # 1 was the same as above except it was serial # 394. Sights were cross wired added to clear clover leaf recticule, in January 1934.
This battery had two T.R. back Hoists in a room that was 9' X 24', on the East side of the battery and a smaller on the West side that was 9' X 21', with a passage way front and back of the hoist, there Serial Number were 40 and 50, made by G.E. Company with 7 1/2 H.P. motor and used 110 Volts with 800 R.P.M. and used a R. 96-A control and was transferred Sep 30 1915. In the journal dated April 22 1914 (93819) the D.E.O. was informed that it is proposed to manufacture two new Taylor-Raymond projectile hoists adapted to handle the new long pointed projectiles in place of the two Hodges installed in this battery.
On May 29 1900, plans and estimates having been requested for a site for this battery, examinations were began and a site was selected. The money allotted on July 25, 1900 was $1,000.00, the next was October 31, 1900 which was $114,710.00 and the last was on April 20, 1901 $ for $6.000.00.

The one problem was, the distance between the wharf and the site over several miles over a mountainous road with an elevation of 640 feet at the highest point, and the cost of bringing supplies over this road, so it was deemed best to make a hydrographic survey of a sheltered cove to determine whether a wharf could be built. The side was selected, the depth of the outer being 26 feet. To connect the wharf approach with good ground above by a road was too expensive, hence a tramway, designed to carry loads up to 6 tons was built.
Construction of this battery began in July 22 1900 with the grading and clearing of the site, so that the excavation could start. A week later the main excavation of over 24,830 cubic yards of dirt and sand was taken from the battery site. Where batteries sites in this harbor are on elevated positions, they are generally located on ridges where foundation material is usually rock and shales tending to rock. An exception to this rule was found at this 12" disappearing gun battery at the point where most of the work has been concentrated. The site is elevated but the surface dipped back from the face of the cliff, below the rock was about parallel with the surface, but 40 feet and more below. The soil overlying the rock was for the most part light yellow clay, while some portion of it were sandy clay. When excavated and placed in a spoil bank it settled 20 per cent, and it has since given a good deal of trouble where deposited as backfill on the right flank the battery.
A foundation bed of that character could not be depended upon to carry the loading designed for the work, the greatest being a concentrated load of about 30 tons per square foot. The entire area therefore was excavated to the grade of the bottom of the gun platforms, or about 3 feet 6 inches below the service room floors, and refilled with Portland cement concrete. No iron or steel work was added to lessen the quality of the concrete, for the reason there were no old rails on hand or could any be obtained on the market cheaply at the time. This proved to be a precaution for not only was concreting prosecuted all through the winter months with perfect safety, but no appreciable settlement has since detected anywhere in the emplacement. as the excavation was started and progressed also, at this time the work on the forms was started. On the timber used in making the forms, in all cases dressed lumber will be used. As the forms are finished, the inserting of the reinforcement which was weighted before adding, in this battery there was used 102,149 lbs, plus the Maneuvering Ring, there were five in each emplacement in this large battery.
The concrete used in this battery was over 9010 cubic yards of concrete and over 2,349 cubic yards of finished cement. All outside walls of the magazines and the parapets are made of concrete mixed 1:3:8. Bolder stones have been embedded in these to the height of the ceiling. The concrete was deposited in layers 6" thick, the beds of which slope to the front on an incline of about 1 in 10. It was similarly deposited in the roofs, where concrete was made slightly richer in time material and in cement: no boulder stone was placed in either roof and bearing walls (walls supporting beams) The steel work to carry the masonry of the roofs, instead if using I Beams the new twisted steel was used being much cheaper. The service rooms and shot galleries under the loading platforms are separated from the gun block by 6" tile. the 2 inch tile placed in the ceiling pitches from all sides into the wall. The use of a waterproofing course of tile, laid horizontally in the loading platform, has proven a good measure. There has been no sign of moisture in any of the rooms during the past two winters, excepting at one point where the platform, in joining the traverse, was not properly constructed. The fault has since been corrected. . and was completed in, 1902 (except as to minor details, work incident to setting base rings, delivering and mounting ordnance, the mounting of the gun # 4b on carriage #30 in Empt #1 was completed August 1904 and the mounting of gun # 6 on carriage # 31 in Empt #2 was completed October 1904, battery was wired for electric but the plant was not installed, also the traversing, elevating, depressing or retracting motors not installed).
This battery was 274' across the front and 80' deep and 137' between the guns of this two story battery, it also had a Latrine which was 8' X 14' and one 8' X 9' and Engine Room that was in two parts with a wall about 32' long one side was 10'-6" X 29 and the other 10'-6 X 29', with an alcove for storage in the front of the one side, I would think that the Engines were in one side and the Generators were in the other, there was also a Radiator Room behind these rooms with sliding door and it was 8' X 15'-6", there was also 2 Oil Rooms, one that was 28'-6" X 22'-6" one the East side of the battery , the other was a little smaller, and was 10' X 13'-9" on the West side of the battery, a Plotting Room which was 11'-6" X 14", a Store Room which was 10'-6" X 41' and a Guard Room , that was 11'-6" X 19'-6", it also had a smaller Oil Room on the West side of the battery, that was 10' X 13'-9", and the B.C. Station was 7' X 7', The elevation of this battery was 236 feet and the distance between the guns was 133 feet.
To move the guns and carriages up to the battery, they used 51/4 manila rope through blocks, and with four horses each of the sets of two capstans taking the gun a placing it on a cradle. The slope was about 221/2 and the weight 130,000 (Gun and Cradle), and the slope was 470 feet, and required 12 hours to take up to the battery.
This battery was transferred on June 8, 1905 at cost of $128,016.00.
There were three units for the power of this battery, which were the following: G.E. 12-43/560 made by the General Electric Company: these engines are of the four cycle, four cylinder, single acting vertical type. They are directly connected to a generator, Type M.P.C. Class 6, -25 kw., -560 R.P.M., and are each capable of operating its generator at full load indefinitely, and at a 25% overload for two hours, furnishing in each case 2.5 kw, additional for operating radiator fans.
Battery Mendell was originally equipped with three of the above type generating sets, but the set listed below was removed and installed at Tennessee Point as one of the power plants for Searchlights #1 and 2 on March 8th 1919, the engine # for it was 5444 and the Generator # was 183200,All three were installed in November 11 1910, the other two left in the battery Engine # was 5454 and 23, and the Motor Generator # was 177331 & 183202, they were located on the left flank of Battery Mendell in rooms beneath the loading platform of emplacement #2, and the existing vertical protection against hostile fire consists of approximately 3 feet of concrete: the minimum horizontal protection against attack from the sea consists of 15 feet of concrete and 40 feet of earth.
This battery required 16.4 kw for the lights in the battery, and 23.2 kw for the motors for the gun carriages, and the hoist motors. The two hoist motors are each 71/2 HP, the size originally supplied with the 12" Taylor-Raymond hoist. Since the latter were installed, however alternate carriers have been removed from the chain of each hoist, thus reducing the possible load on the motors by perhaps 40%. The amount of current to operate the hoist continuously under a full load would be 31/2 k.w. per hoist, and that should be ample. The retracting motors are chiefly for peace time service since during hostilities the guns would ordinarily be thrown out of the battery by there recoil.
The for data transmission was by telephone and speaking tube, it's ventilation was natural draft three 8" dia flues from each magazine terminating in the emplacement walls, and was connected to both water and sewer, with a siphon latrine. Trunion elevation in battery was 235.7, Datum M.L.L.W. Traverse in Azimuth, Emplacement #1 Left-320 Right-132 Emplacement #2 Left-322- Right-100. Power for the fortifications was furnished to Battery Memdell and all the fire control stations on Point Bonita, (4), type B Switchboard and a mining casemate, and in June 16 1932 a power line was tapped into the Fort Barry Radio Station, under construction that date.
Fire Control
The Plotting Room for this battery was originally in another part of the battery or outside the battery, but in March 1 1915, it was changed inside in the rear of the battery, between emplacement #1 and #2, and had the following equipment. 1 Pratt Range Board #28, 1 Deflection Board, F.A. Model 1905; # 323, 1 Wind Component Indicator, Model 1906; # 89, 1 Plotting Board, 110-degrees, Model 1915; #89, 1 Cover, canvass, 1 Screwdriver, 1 Target for Plotting Board, this list was brought to date on March 27 1935, there was also 9 Wall Telephones, C.A.T., EE-27, 2 Telephones, Plotter, s Wall, C.A.T., EE-25, 9 Headset Telephones, C.A.T., EE-70, and 1 Handset, Telephone, EE-69, this equipment was also brought up to date July 31 1940. There was updated in March 11 1941, Drift and Range-time Scales, Model 1905, Range Correction Charts (Pratt Range Board), Range-Range Relation Scales for: # 1070 and # 870, Prediction Scale (110o Plotting Board, Model 1915). The B.C. for this battery was located between the guns at the Crows Nest, N2471.54--W.5258.07, and was constructed March 1909, Height of Axis above MLLW: 235.8 feet, Field of View: Left 350 deg. Right 133 deg, Height of top of pedestal above MLW-?, the equipment in this B.C. was 1 Wall Telephone, C.A.T., EE-27, 2 Telephones, B.C., C.A.T., BE-6, 5 Headsets, telephones, C.A.T., EE-70, 1 Box telephone, EE-78, (This was brought up to date July 31 1940). The B Station was constructed in 1917, Limiting azimuths of field of view, R-172o - L 341o, Height above MLW of axis of instrument was 73.8 feet, Height above MLW of top of Pedestal was?, and was equipment with 1 Warner-Swasey D.P.F., Type A-40.60, 3 Wall Telephones, C.A.T., EE-27, 3 Headset, Telephone, C.A.T., EE-27, 3 Headset Telephones, C.A.T., EE-70, 1 Handset, Telephone, EE-69, 1 Headset Switch. B1S1 was a double wooden station at an elevation of 74 feet on Point Bonita and B2S2 was at Fort Miley at an elevation of 354 feet, this was to be rebuilt by the Golden Gate Bridge Company on the same site as a double dug-in station at an elevation 354 feet. B3S3 was to be constructed at Frank Valley at an elevation of 480 feet and was to be a double dug in station for covering the northern waters B4S4 was at Point Bonita at an elevation of 227 feet, it was a temporary wooden structure that was to be rebuilt as a double-dug in type on the same site, so as to provide station of a relatively high site and low site arrangement at Fort Barry (B1S1) either would serve in case of damage to the other. The two baselines would be B1S1 or B4S4 with B2S2, approximately 5,200 yards; B1S1 or B4S4 with B3S3. 7,000 yards. There was also one S Station, which was constructed 1920, Limiting azimuth of field of view, R 148o-L 290o, Height above MLW of axis of instrument was 73.8 feet, and had 1 Warner-Swasey D.P.F., Type A 11, # 169.
Its guns were salvaged in August 1943, the guns and carriages were sold as junk, the dismantling letter service of supply, file # SPX662 was issued April 22 1943, this being the last disappearing carriage battery to be removed from service, This battery is not in the best condition, (Erosion and Vandalism) but is still open to the public.


 Photographs provided courtesy of Brian B. Chin

Layout of Battery Mendell





. Drawing courtesy of Mark Bernow, Coast Defense Study Group

Battery Mendell, circa 1910
Images courtesy of Mr. Bob Ebbeskotte

Battery Mendell Today


An aerial view of Battery Mendell, April 2000. Photo by Kite Aerial Photography


A view of Battery Mendell from the more modern Battery Wallace, October 2000


Gun emplacements, October 2000 


 A rear view of Battery Mendell. Note the scaffolding and other evidence of the National Parks Service's restoration efforts. October 2000
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