221. Helicopter Creator: Watertown Arsenal (Mass.) Format: Photographs Collection: Watertown Arsenal Photographs Date: [ca. 1908–1962] Institution: National Archives at Boston
222. Helicopter Creator: Watertown Arsenal (Mass.) Format: Photographs Collection: Watertown Arsenal Photographs Date: [ca. 1908–1962] Institution: National Archives at Boston
223. Howell 10" disappearing carriage Creator: Watertown Arsenal (Mass.) Format: Photographs Collection: Watertown Arsenal Photographs Date: January 1913 Institution: National Archives at Boston
224. Howell disappearing carriage Creator: Watertown Arsenal (Mass.) Format: Photographs Collection: Watertown Arsenal Photographs Date: January 1913 Institution: National Archives at Boston
225. Improved bonding of copper rotating bands to titanium artillery shells Creator: U.S. Army Materials and Mechanics Research Center. Public Affairs Office Format: Photographs Collection: Watertown Arsenal Photographs Date: [ca. 1980–1984] Institution: National Archives at Boston
226. Krupp 12 pr. balloon gun on transportable platform Creator: Watertown Arsenal (Mass.) Format: Photographs Collection: Watertown Arsenal Photographs Date: November 1914 Institution: National Archives at Boston
227. Loading platform extension 305 MM sliding RR mount Creator: Watertown Arsenal (Mass.) Format: Photographs Collection: Watertown Arsenal Photographs Date: [ca. 1908–1926] Institution: National Archives at Boston
228. Loading platform for 305 MM railway mount Creator: Watertown Arsenal (Mass.) Format: Photographs Collection: Watertown Arsenal Photographs Date: [ca. 1908–1926] Institution: National Archives at Boston
229. Loading platform for 305 MM railway mount Creator: Watertown Arsenal (Mass.) Format: Photographs Collection: Watertown Arsenal Photographs Date: [ca. 1908–1926] Institution: National Archives at Boston
230. Loading platform for 305 MM railway mount Creator: Watertown Arsenal (Mass.) Format: Photographs Collection: Watertown Arsenal Photographs Date: [ca. 1908–1926] Institution: National Archives at Boston
231. Loading platform for 305 MM railway mount Creator: Watertown Arsenal (Mass.) Format: Photographs Collection: Watertown Arsenal Photographs Date: [ca. 1908–1926] Institution: National Archives at Boston
232. Loading platform for 305 MM railway mount Creator: Watertown Arsenal (Mass.) Format: Photographs Collection: Watertown Arsenal Photographs Date: [ca. 1908–1926] Institution: National Archives at Boston
233. Lodge-Shipley engine lathe Creator: Watertown Arsenal (Mass.) Format: Photographs Collection: Watertown Arsenal Photographs Date: September 25, 1922 Institution: National Archives at Boston
234. Man with ordnance Creator: U.S. Army Materials and Mechanics Research Center. Public Affairs Office Format: Photographs Collection: Watertown Arsenal Photographs Date: [ca. 1980–1984] Institution: National Archives at Boston
235. Man with ordnance Creator: U.S. Army Materials and Mechanics Research Center. Public Affairs Office; Watertown Arsenal (Mass.) Format: Photographs Collection: Watertown Arsenal Photographs Date: [ca. 1967–1984] Institution: National Archives at Boston
236. Man with ordnance and onlookers Creator: U.S. Army Materials and Mechanics Research Center. Public Affairs Office Format: Photographs Collection: Watertown Arsenal Photographs Date: [ca. 1980–1984] Institution: National Archives at Boston
237. Men and gun Creator: Watertown Arsenal (Mass.) Format: Photographs Collection: Watertown Arsenal Photographs Date: [ca. 1908–1926] Institution: National Archives at Boston
238. Men and military officer with gun Creator: Watertown Arsenal (Mass.) Format: Photographs Collection: Watertown Arsenal Photographs Date: [ca. 1942–1959] Institution: National Archives at Boston
239. Men and military officers inspecting ordnance Creator: Watertown Arsenal (Mass.) Format: Photographs Collection: Watertown Arsenal Photographs Date: [ca. 1942–1959] Institution: National Archives at Boston
240. Men and women viewing sight of mock guns Creator: Watertown Arsenal (Mass.) Format: Photographs Collection: Watertown Arsenal Photographs Date: [ca. 1942–1959] Institution: National Archives at Boston