<p>Allen got another chance when Brigadier General Irvin McDowell's troops moved out in the first Manassas campaign in July 1861. Both balloons were inflated with coal gas at a plant in Alexandria, Virginia, the morning of 14 July. One burst; it was old and in poor condition. The second was man-handled along the road toward Falls Church, but a gusty and strengthening wind drove balloon and handling crew off the road and toward a canal. A telegraph pole impaled the balloon; it collapsed in a final sigh of gas, and ended Allen's early hopes of service to the Union cause.
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<p>The Topographic Engineers' office had enough faith to keep trying. On 26 June they telegraphed the experienced balloonist John Wise for an estimate of the cost and delivery date of a new balloon of 20,000-cu ft (566-m<su>3</su>) capacity, made of the best Indian silk and with linen cordage. Wise replied that it would take two weeks and cost $850.
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<p>Wise was appointed a balloonist in the Federal service on 1 July 1861. He was 53 years old, with more than a quarter-century of ballooning experience behind him. The balloon was finished on 16 July and moved to Washington. Ordered to Centerville, Virginia, and duty with General McDowell's headquarters, Wise and the inflated balloon started out in the early light of 21 July. He met Major Albert J. Myer, Signal Officer of the Army, and commander of the unit that would take the balloon to battle. Myer was impatient; he could hear the guns of battle ahead and, seeking faster transport, ordered that the balloon be moored to a wagon and towed by a team of horses. The hitch was made, and the horses were urged into a trot. Near Fairfax Courthouse, the inevitable happened. The balloon was snared by the thick foliage of the trees lining the road. Over Wise's objections, Myer ordered the wagon ahead. The balloon tore and collapsed, and the first Battle of Bull Run was fought without aerial reconnaissance.
