Amiel Weeks Whipple, Union army officer and surveyor, the son of David and Abigail (Pepper) Whipple, was born on October 21, 1817, in Greenwich, Massachusetts. He spent part of his youth in Concord, where his father ran an inn. In 1836 Whipple attended Amherst College for a year before his appointment to the United States Military Academy at West Point. He graduated fifth in his class in 1841 and was commissioned in the First Artillery. He was transferred to the Topographical Engineers shortly afterward. During the next three years he was engaged in hydrographic surveys of the Patapsco River in Maryland, the approaches to New Orleans, and the harbor at Portsmouth, New Hampshire. At Portsmouth he met Eleanor Mary Sherburne, whom he married on September 12, 1843. They had four children, one of whom died in infancy. From 1844 to 1849 Whipple handled the instrumental work for a survey of the northeast boundary of the United States. As an assistant with the United States Boundary Commission, he helped survey the new boundary with Mexico west from El Paso and along the Gila River to the Pacific. Whipple worked closely with commissioner John R. Bartlett, whom he accompanied across Texas from Indianola through San Antonio to El Paso in the fall of 1850. Along the way he made several astronomic and magnetic observations, and he erected an observatory at San Elizario in December and another at Rancho Fronteras, eight miles from El Paso, the following February. He acted as the project's chief surveyor for a time before Col. William H. Emory's appointment to that position. Whipple was promoted to first lieutenant on April 24, 1851, and completed his boundary survey report by spring 1853.
Since he had experienced firsthand the frequent dangers and privations of the desert Southwest, Whipple was chosen by the War Department to direct the survey of a possible transcontinental railroad route along the thirty-fifth parallel from Fort Smith, Arkansas, to Los Angeles (see WHIPPLE EXPEDITION). With him were eleven civilian scientists, including J. M. Bigelow, surgeon and botanist; Jules Marcou, Swiss geologist and mining engineer; and Heinrich Balduin Möllhausen, German artist and student of Alexander von Humboldt. Whipple and his command left Fort Smith on July 14, 1853, worked their way up the Canadian River, and on September 6 camped at the Antelope Hills in what is now Shackelford County. In the Panhandle Whipple followed trails marked by Josiah Gregg in 1840, James W. Abert in 1845, and Randolph B. Marcy and James H. Simpson in 1849. The expedition was briefly guided by Comancheros and Pueblo Indians from New Mexico who happened to be in the area. Whipple had frequent contacts with roving bands of Comanches and Kiowas, with whom he exchanged presents and whose behavior was unpredictable. At one point he peacefully but unsuccessfully sought to ransom some Mexican captives. On September 11 he passed by the ruins of Bent's Fort Adobe, or Adobe Walls in what is now Hutchinson County. Near the site of present-day Sanford, the expedition left the Canadian and ventured over Marcy's route across the Llano Estacado to Anton Chico, New Mexico, before pushing on to Arizona and California. At Los Angeles the expedition disbanded, and Whipple and several others sailed back to New York City. In his report Whipple confirmed the feasibility of the thirty-fifth parallel route for a railroad. Bigelow, Marcou, and the other scientists had collected specimens and geological data. Möllhausen's paintings and reports sparked interest throughout Europe and led to lengthy correspondence between Whipple and Humboldt. Except for the Civil War and Reconstruction politics, the Canadian valley might have been included in the first transcontinental railroad. Whipple was the last of the antebellum pathmarkers to venture across the Panhandle, though he incorrectly identified some of the creeks Simpson had labeled, thus misleading many later historians who used his itinerary.
When the Civil War broke out Whipple drew the Union Army's first maps of the northern Virginia theater of war and was appointed chief topographical engineer on the staff of Gen. Irvin McDowell. He participated in the first battle of Bull Run (Manassas) on July 21, 1861, and became friends with President Lincoln. In September 1862 Whipple was assigned to the Third Army Corps, and on December 13–15 participated in the battle of Fredericksburg, Virginia. At the battle of Chancellorsville, which started on May 2, 1863, the Third Corps, commanded by Gen. Daniel E. Sickles, advanced into an exposed position between Robert E. Lee's and Stonewall Jackson's Confederate forces. Whipple was shot in the stomach by a Confederate sniper while supervising construction of some earthworks near a battery on May 4. He was taken back to Washington, where he died on May 7, 1863. Just before Whipple's death President Lincoln signed his promotion to major general of volunteers. Whipple was posthumously awarded more brevets for his wartime services, and both of his sons received presidential appointments to the military academy of their choice. Fort Whipple, now part of the Fort Myer reservation near Alexandria, Virginia, is named in his honor.