On the following afternoon Banks entered New Iberia. Here the ways parted, the right-hand road by Saint Martinville following for many miles the windings of the Teche, while the left-hand road leads almost directly to Opelousas, by way of Vermilionville, now called Lafayette.
Beyond Indian Bend the lowlands, in many places below and nowhere much above the level of the adjacent waters, may be said to end and the plains to begin; and soon after leaving New Iberia and Saint Martinville the troops found themselves on the broad prairies of Western Louisiana, where the rich grasses that flourish in the light soil sustain almost in a wild state vast herds of small yet fat beeves and of small yet strong horses; where in favored spots the cotton plant is cultivated to advantage; where the ground, gently undulating, gradually rises as one travels northward; where the streams become small rivers that drain the land upon their borders, instead of merely bayous taking the back waters of the Mississippi and the Red. Near the right bank of the Teche runs even a narrow ribbon of bluffs that may be said to form the western margin of the great swamps of the Atchafalaya. Along the streams live-oaks, magnolias, pecans, and other trees grow luxuriantly; but, for the most part, the prairies are open to the horizon, and at this time, though the gin-houses were full of cotton, the fields were mainly given over to the raising of corn for the armies and the people of the Confederacy.
From New Iberia Banks ordered Grover to send a detachment to destroy the famous Avery salt-works, on Petit Anse Island, distant about twelve miles toward the southwest. On the 17th of April, Grover accordingly dispatched Kimball on this errand, with his 12th Maine, the 41st Massachusetts, one company of the 24th Connecticut, and Snow's section of Nims's battery. The extremely rich natural deposit of rock salt was, at that time, in the hands of the Confederate government, being, indeed, the main source of supply of this indispensable article for the whole Confederacy, especially for the region between the Mississippi and the Atlantic. The works required for its extraction are, however, very simple, for the deposit lies close to the surface, and has only to be quarried in blocks of convenient size. These, always as clear and beautiful as crystal, have only to be crushed or broken to be ready to use for common purposes, and when pulverized, however rudely, yield the finest table salt. Kimball burned all the buildings, destroyed the engines and implements, with six hundred barrels of salt, and marched back to New Iberia, and, on the 19th, rejoined Grover on the Vermilion. The Confederates having drawn off the detachment and the guns previously posted to guard the works, Kimball met with no opposition.
On the 17th of April, Grover, with the main body of his division, reinforced by Gooding's brigade, temporarily commanded by Colonel John W. Kimball, of the 53d Massachusetts, continued the pursuit toward Vermilion, while Banks, with Weitzel and Emory, marched to Saint Martinville, on the Teche.
Early in the afternoon Grover caught sight of Green's rear-guard of Taylor's retreating forces, then about two miles distant, and in the act of crossing the Vermilion. Before Grover could overtake them, the bridges were in flames. Dwight's skirmishers deployed on the right and left of the road, and, with the help of the guns of Closson and Nims, drove off the enemy, posted to hinder or prevent the work of reconstruction. In this affair Dwight lost one killed and five wounded. The next day, the 18th of April, was spent by Grover in rebuilding the main bridge.
Then began to be felt the need of such a force of mounted troops as on these plains formed the main strength of Taylor's little army, and the source of its safety; for Banks's cavalry, taken as a whole, with some splendid exceptions, was at this time greatly inferior, not only in numbers but in fitness for the work at hand, to the rough riders led by the restless and indomitable Green. A few more horsemen, under leaders like Barrett, Williamson, and Perkins, would have saved the bridge and insured the dispersion or the destruction of Taylor's force.
Weitzel, who, as far as Saint Martinville, had led the advance of the main column, followed by Emory with Paine and Ingraham, there took the road to the left and halted on the evening of the 17th of April at Côte Geleé, four miles in the rear of Grover. The next morning Weitzel moved up to Grover's support, while Banks, with Emory, rested at Côte Geleé to await the rebuilding of the bridge.
From St. Martinville, Emory sent the 173d New York, under Major Gallway, with Norris's section of Duryea's battery, to follow the Teche road to Breaux Bridge and endeavor to capture the bayou steamboats, five in number, that were still left to the Confederates. Five miles below the village of that name, Gallway met a small Confederate picket, and pushing it aside, soon afterward found the bridge over the bayou in flames. On the morning of the 18th he learned that four of the boats had been burned by the Confederates, and about the same time his farther advance was stopped by orders from Banks, despatched as soon as it was known that Grover had been brought to a stand. A courier from headquarters having lost his way in the night of the 18th, on the following morning Gallway found himself in the air without any apparent object. He accordingly marched along the banks of the Teche and the Bayou Fusilier, and taking the road to Opelousas, there rejoined Paine on the 1st.
On the 19th of April the army crossed the Vermilion and the Carencro, and marched unopposed sixteen miles over the prairie to Grand Coteau. Gooding's brigade rejoined Emory during the day.
On the 20th the march was continued about eight miles to Opelousas.
Just outside the town the Corps went into bivouac, after throwing
forward all the cavalry, the 13th Connecticut, and a section of
Rodgers's battery, to Washington, on the Courtableau.