Lowe was always active and adaptable. His balloons were brought into action from horse-drawn carts, from railroad wagons, and even from the decks of boats. At one stage he operated a tethered observation balloon from a coal barge, the Rotary, sailing up and down the Potomac River. He afterward claimed it was the first “aircraft carrier” —although his rival John LaMountain had done the same thing on the James River. He was prepared to inflate his balloons from coal-gas mains, hydrogen field generators, or cobbled-together barrels of sulfuric acid and metal shell casings. On one emergency occasion, he even used another balloon, “transfusing” the gas from his small Constitution via a makeshift valve (“contrived from a convenient kettle”) into the larger Intrepid.
Lowe himself had no doubts as to the impact of his Balloon Corps in the early months of the Peninsula Campaign. As he put it graphically: “A hawk hovering above a chicken yard could not have caused more commotion than did my balloons when they appeared before Yorktown.” Rebel sources seemed to agree: “At Yorktown, when almost daily ascensions were made, our camp, batteries, field works and all defenses were plain to the vision of the occupants of the balloons. … The balloon ascensions excited us more than all the outpost attacks. … ”
Military observation with binoculars was a delicate art. A tethered balloon was rarely stable—at 500 feet in any kind of wind, Lowe found the balloon “very unsteady, so much so that it was difficult to fix my sight on any particular object.” At a thousand feet he could see 12 miles and a whole battlefield, yet always “indistinctly” because of the dust, smoke, and heat haze produced by masses of troops on the move. Even more, the heavy silver-gray smoke produced by field guns in action might temporarily block out the ground altogether.
Lowe communicated his observations by various means. Ideally, he used a telegraph key operated from his balloon basket, transmitting messages down a 5,000-foot telegraph cable directly to McClellan’s headquarters. But bad conditions often made this impossible—the equipment could be too heavy to take aloft, or the cable could break. In that case Lowe would make notes and drop them in canisters to a telegraph operator on the ground. He did the same with rapidly drawn sketch maps of the enemy positions, which were then delivered to McClellan by runner. On other occasions he used signal flags, colored flares or simply hand-gestures. If all else failed, he would have himself winched down so he could deliver his observations in person, sometimes galloping to the headquarters on his favorite gray mare, a procedure he apparently enjoyed.
Lowe had promised to supply McClellan with strategic aerial photographs, which he said could be examined by giant magnifying glasses once delivered to the ground. He claimed optimistically that a 3-inch-square glass negative would provide the equivalent of a “20 foot panoramic image” of a battlefield. He took aloft several professional photographers—“[Matthew] Brady the celebrated War photographer was also much interested in the work of the Corps, and spent much time with us.” Yet no such aerial photographs have survived. While there are thousands of Civil War photographs taken on the ground, there is not a single known photograph of a Civil War battlefield taken from a balloon. Probably cameras, glass negatives and chemical developing equipment proved too cumbersome for the tiny observation baskets. Or perhaps the whole process was simply too slow to be of any practical use. Timing was vital, because what Lowe had discovered was the highly mobile nature of battlefield observation. This transformed the traditional idea of the tranquil, all-seeing “angel’s-eye view” from a balloon. In warfare, the panoptic vision no longer provided the classic, unfolding “map” of the world beneath. Instead it revealed a constantly moving game-pattern, a shifting topography of hints and clues, secrets and disguises, threats and opportunities. An entire tactical situation could change within a matter of hours, or even minutes.
Visual clues had to be carefully sought out: smoke from campfires, rising road dust, sun glinting on armory, newly dug patches of raw earth, the straight lines of fresh infantry trenches, the faint dimpled shadows of breastworks, the regular white circles of bell tents, the deep curving tracks left by heavy guns. Lowe writes on one occasion of taking a general “to an altitude that enabled us to look into the windows of the city of Richmond.” The battle landscape had to be read constantly, interpreted shrewdly, and summarized with the utmost speed.
One of Lowe’s most brilliant observational coups was the discovery of the Confederates’ secret evacuation of Yorktown, under the cover of darkness, on the night of May 4–5, 1862. This gave the Union Army one of its most crucial tactical advantages in the whole Peninsula Campaign. At the time it was thought that Yorktown was being resupplied, and stiffening its defenses against the Union’s long siege. Lowe’s account is vivid, and turns on a single, precisely observed detail. First of all he sets the scene: “The entire great fortress was ablaze with bonfires, and the greatest activity prevailed, which was not visible except from the balloon. At first the General [Samuel P. Heintzelman] was puzzled on seeing more wagons entering the forts than were going out.”
This was apparently clear evidence of resupplying. Lowe, however, observed and interpreted more carefully: “But when I called his attention to the fact that the ingoing wagons were light and moved rapidly (the wheels being visible as they passed each campfire), while the outgoing wagons were heavily loaded and moved slowly, there was no longer any doubt as to the object of the Confederates. They were withdrawing.”
According to Lowe, his observations of this secret evacuation carried instant conviction to the highest command level: “General Heintzelman then accompanied me to General McClellan’s headquarters for a consultation, while I with the orderlies, aroused other quietly sleeping corps commanders in time to put our whole army in motion in the very early hours of the morning, so that we were enabled to overtake the Confederate Army at Williamsburg.” The result was one of the few decisive victories of the Union Army of the Potomac, which was otherwise becoming characterized by its lack of decision and initiative. By the end of May, McClellan was within 5 miles of Richmond.
Excerpted from Falling Upwards: How We Took to the Air by Richard Holmes, out now from Pantheon.