| Date | Event |
|---|
| 1839, Mar. 21 | Born, Blackstone, Mass. |
| 1861, Nov. 22 | Enlisted, Boston, Mass., in Co. A, Topographical Engineers |
| 1862, Jan. 13 | Transferred to Co. B, U. S. Engineer Battalion |
| 1862, July 1 | Transferred to Co. D, U. S. Engineer Battalion |
| 1862, Dec. 17 | Advanced to rank of corporal |
| 1864, Nov. 21 | Discharged, Camp Woodbury, Va. |
| 1865, Jan. 4 | Civilian assistant engineer, headquarters, Army of the Potomac |
| 1869, Sept. 28 | Married Mary Frances McNeill in Washington, D.C. |
| 1872, May | Daughter Amy Greer Thompson born |
| 1872, June | Topographer, Office of Explorations West of the 100th Meridian |
| 1880, May 1 | Topographer, U. S. Geological Survey; by 1885, geographer for the U. S. Geological Survey |
| 1881 | Joined Grand Army of the Republic |
| 1883 | Joined Society of the Army of the Potomac |
| 1890 | Organized the District of Columbia Engineer Corps |
| 1909, June 8 | Died, Washington, D.C. |
