The Island’s “temporary” gun batteries continued to be considered part of the Bay’s military defenses during the 1870’s and 80’s, despite being seldom used and poorly maintained.  Exposure to the elements eroded the batteries’ earthwork emplacements, rotted wood and rusted iron carriages and fittings.  In 1869 the battery at Point Blunt was already described as “partially dismantled.”  By 1887 the condition of the Island’s defenses was so bad that one report concluded that only the batteries at Points Knox and Stewart still had cannon mounted and that although these could still be fired “...once as they are now pointed.  The result must be conceived to be the final dissolution of all that remains...”  Between 1898 and 1901 the Army finally upgraded the Island’s defenses when four steel breech-loading guns were mounted in the new concrete batteries of Drew, Wallace and Ledyard.  Additionally, in 1898 two 1860’s Rodman Columbiads, ‘modernized’ by having been converted to rifles, were positioned at Point Knox, only to be removed in 1900.  By 1909 the Army had decided that Angel Island’s armament was unnecessary and deactivated all the batteries, the guns of which were removed within a decade.

      Today the Park demonstrates cannon firing with a replica of a much smaller gun that was also used in the mid-late 1800’s- the 12 Pdr. Mountain Howitzer.   Although large seacoast cannon such as Columbiads and smaller field pieces like the Mountain Howitzer worked on the same basic muzzle-loading principles, the intended roles of these two types of ordnance were very different.  The large cannon originally mounted on Angel Island were designed to be fixed in one location and used primarily to hurl heavy projectiles at attacking ships.  The 12 pdr. Mountain Howitzer was a highly mobile piece which was intended to be taken with the Army in rough terrain (especially mountains) and used against formations of enemy troops. 

      Although relatively tiny, the replica bronze Model 1835 12 pdr. Mountain Howitzer fired at Camp Reynolds today is an example of a very useful type of cannon that saw much active service in its career.   Designed to provide battlefield fire support for infantry and cavalry units, the farthest the Mountain Howitzer could throw its 8.9-pound shell was 0.57 miles.  The Mountain Howitzer was most commonly used to fire special antipersonnel rounds called spherical case and canister.  The spherical case consisted of a hollow iron sphere like the shell but instead of simply being filled with gunpowder it also contained a number of metal balls which would increase the round’s lethal effect upon detonation.  The Mountain Howitzer’s 11-pound spherical case contained 82 lead .69 caliber musket balls packed in sulfur and had a range of up to 0.46 miles.  At extreme close ranges (250 yards or less) the Mountain Howitzer could instead fire an 11.2-pound canister round which consisted of 148 .69 caliber musket balls packed in sawdust in a sheet-metal can.  On firing the can would disintegrate and the lead balls would spread out in a wide arc of destruction.  The standard Mountain Howitzer ammunition chest held eight rounds: two shells, five spherical case and one canister.

       Besides its ammunition, the lightweight and portable design of the Mountain Howitzer increased its versatility.  The gun was designed so that it could be broken down; the tube (220 lbs.) packed on one mule, the carriage (287 lbs.) on a second and three more mules each carrying two ammunition chests (approx. 100 lbs. each).  This gave the Army an artillery piece that could be carried into areas that did not have good roads, which was especially important during the campaigns against the Native Americans in the 1800’s.  A trained Mountain Howitzer crew of seven was expected to be able to unpack, assemble, load, aim and fire the gun in under a minute and be able to sustain a rate of fire of two shots per minute after that.