Organised at bangor as 18th infantry and mustered in august 21, 1862. Left state for washington, d.C., august 24. Designation changed to 1st heavy artillery january 6, 1863. Company “l” organized january, 1864, and company “m” february, 1864. Attached to defenses of washington august, 1862, till february, 1863. 2nd brigade, haskins’ division, 22nd army corps. Defenses north of the potomac to may, 1864. 2nd brigade, 4th division, 2nd army corps, army of the potomac, to may 24, 1864. 1st brigade, 3rd division, 2nd army corps, to july, 1864. 2nd brigade, 3rd division, 2nd army corps, to june, 1865. 3rd brigade, hardin’s division, 22nd corps, to september, 1865.Battles: duty in the defenses of washington, building and garrisoning batteries and forts. Eight companies at fort alexandria, company “e” at batteries vermont and mattox, company “k” at batteries cameron and parrott, august 26, 1862, to may 15, 1864. Moved to belle plains, virginia., may 15, 1864, as a part of tyler’s heavy artillery division. Rapidan campaign may 18 to june 15. Harris’ farm, fredericksburg road, may 19. On line of north anna may 20-23. North anna may 23-26. On line of the pamunkey river may 26-28. Totopotomoy may 23-31. Cold harbor june 1-5. Barker’s mills june 5-12. Before petersburg june 16-19. Hare’s house, assault on petersburg, june 18. (sustained greatest loss of any one regiment in any one action of the war. 635 killed and wounded out of 900 engaged.) siege of petersburg june 16, 1864, to april 2, 1865. Weldon railroad june 22-23, 1864. Picket duty at deserted house till july 23. Demonstration on north side of james river july 27-29. Deep bottom july 27-28. Duty at hare’s house till august 12. Demonstration on north side of james river august 13-20. Strawberry plains august 14-18. Near fort sedgwick till september 30. Poplar springs church september 30-october 2. Yellow house october 1. Squirrel level road october 2. At fort sedgwick october 6-24. Boydton plank road, hatcher’s run, october 27-28. Warren’s hicksford raid december 7-12. Hatcher’s run february 5-7, 1865. Armstrong house march 25. Appomattox campaign march 28-april 9. South side railroad march 29. Boydton road and white oak ridge march 29-31. Fall of petersburg april 2. Jettersvtlle april 5. Amelia springs and sailor’s creek april 6. Farmville april 7. Appomattox c. H. April 9. Surrender of lee and his army. Moved to washington, d.C., may 9-16. Grand review may 23. Garrison forts in the defenses of washington from fort washington to fort mahone june 27 to september 11. Mustered out september 11 and ordered to bangor, me. Discharged september 20, 1865. Of all regiments in the union armies, this regiment sustained greatest loss in battle. A total 683 casualties made up from 23 officers and 400 enlisted men killed and mortally wounded; 260 dieing of disease. The flags of this unit follow the prescribed pattern for artillery regiments throughout the war. The national flag conforms to the known pattern with regimental designation appearing in stencil upon the flag. The regimental flag has a yellow field with gold painted cannon in the centre and, regimental designations appearing in gold upon a red scroll. Flags associated with this regiment remain in the, maine archives in augusta, maine.