Fort Hancock's Battery Potter, constructed from 1890-1894, was the first disappearing gun battery in the U. S. Originally called Lift-gun Battery #1, it was the first and only disappearing gun battery powered by a steam hydraulic lift system. There is a YouTube video that shows how this worked here: http://youtu.be/PYxqTGxXybA In operation from 1893-1906, it was obsolete by the time it was built because the fastest firing of the gun took over two minutes. Fort Hancock in Sandy Hook, New Jersey.
Sakai Toyo 5x7 large format metal field camera with 4x5 film back.
150mm Caltar-S II F 5.6 lens in Copal BT shutter.
Arista EDU Ultra 200 (re-branded Fomapan) B&W Negative Film, shot at ISO 160.
1/8th second at F32.
Semi-stand development in Rodinal/Adox Adonal 1:100 dilution for 15 minutes in Mod54 daylight tank.
Negative scanned with Epson V600. Cropped to desired size in post.