21. 15 PDR BC M1903 Creator: Watertown Arsenal (Mass.) Format: Photographs Collection: Watertown Arsenal Photographs Date: February 1916 Institution: National Archives at Boston
22. 15 PDR BC M1903 Creator: Watertown Arsenal (Mass.) Format: Photographs Collection: Watertown Arsenal Photographs Date: February 1916 Institution: National Archives at Boston
23. 15 Pounder on BC M1908 Creator: Watertown Arsenal (Mass.) Format: Photographs Collection: Watertown Arsenal Photographs Date: April 4, 1914 Institution: National Archives at Boston
24. 16" Bar. carr. model 1919 Creator: Watertown Arsenal (Mass.) Format: Photographs Collection: Watertown Arsenal Photographs Date: [ca. 1908–1926] Institution: National Archives at Boston
25. 16" Barbette carriage Creator: Watertown Arsenal (Mass.) Format: Photographs Collection: Watertown Arsenal Photographs Date: [ca. 1920] Institution: National Archives at Boston
26. 16" Barbette carriage Creator: Watertown Arsenal (Mass.) Format: Photographs Collection: Watertown Arsenal Photographs Date: [ca. 1920] Institution: National Archives at Boston
27. 16" Barbette carriage Creator: Watertown Arsenal (Mass.) Format: Photographs Collection: Watertown Arsenal Photographs Date: [ca. 1920] Institution: National Archives at Boston
28. 16" Barbette carriage Creator: Watertown Arsenal (Mass.) Format: Photographs Collection: Watertown Arsenal Photographs Date: [ca. 1920] Institution: National Archives at Boston
29. 16" Barbette carriage Creator: Watertown Arsenal (Mass.) Format: Photographs Collection: Watertown Arsenal Photographs Date: [ca. 1920] Institution: National Archives at Boston
30. 16" Barbette carriage Creator: Watertown Arsenal (Mass.) Format: Photographs Collection: Watertown Arsenal Photographs Date: July 26, 1920 Institution: National Archives at Boston
31. 16" Barbette carriage Creator: Watertown Arsenal (Mass.) Format: Photographs Collection: Watertown Arsenal Photographs Date: [ca. 1920] Institution: National Archives at Boston
32. 16" Barbette carriage Creator: Watertown Arsenal (Mass.) Format: Photographs Collection: Watertown Arsenal Photographs Date: [ca. 1920] Institution: National Archives at Boston
33. 16" Barbette carriage Creator: Watertown Arsenal (Mass.) Format: Photographs Collection: Watertown Arsenal Photographs Date: [ca. 1920] Institution: National Archives at Boston
34. 16" Barbette carriage Creator: Watertown Arsenal (Mass.) Format: Photographs Collection: Watertown Arsenal Photographs Date: [ca. 1920] Institution: National Archives at Boston
35. 16" Barbette carriage Creator: Watertown Arsenal (Mass.) Format: Photographs Collection: Watertown Arsenal Photographs Date: [ca. 1920] Institution: National Archives at Boston
36. 16" Barbette carriage Creator: Watertown Arsenal (Mass.) Format: Photographs Collection: Watertown Arsenal Photographs Date: [ca. 1920] Institution: National Archives at Boston
37. 16" Barbette carriage Creator: Watertown Arsenal (Mass.) Format: Photographs Collection: Watertown Arsenal Photographs Date: [ca. 1920] Institution: National Archives at Boston
38. 16" Barbette carriage Creator: Watertown Arsenal (Mass.) Format: Photographs Collection: Watertown Arsenal Photographs Date: [ca. 1920] Institution: National Archives at Boston
39. 16" Barbette carriage, boring recoil band Creator: Watertown Arsenal (Mass.) Format: Photographs Collection: Watertown Arsenal Photographs Date: April 29, 1921 Institution: National Archives at Boston
40. 16" Barbette carriage, boring, turning, facing distance ring Creator: Watertown Arsenal (Mass.) Format: Photographs Collection: Watertown Arsenal Photographs Date: May 5, 1921 Institution: National Archives at Boston