Chapter 7: To Mexico City With Scott

By 1847 American strategy had shifted from northern Mexico in favor of landing an army at Vera Cruz and from there marching on to Mexico City. The conquest of the American Southwest had gone according to plan. American forces had secured the boundary of Texas, and General Taylor's army had successfully penetrated and occupied northern Mexico. Still the Mexican government, despite considerable internal turmoil, would not come to terms with the United States. In Washington Maj. Gen. Winfield Scott's earlier proposal and persistence for the landing at Vera Cruz finally received approval from President Polk. Scott, although the Commanding General of the U.S. Army, had decided that he himself would take to the field to command the expeditionary force.

To carry out these plans Scott worked out a joint operation with the U.S. Navy. The Navy had carried out blockade operations along Mexico's two coasts and occupied several key port towns. Now it came time for the Navy to provide the necessary mobility by transporting an army to the battlefield. Having done that the sea service would then concentrate on operating the transportation and logistical links to the United States.1

General Scott, nicknamed "Old Fuss and Feathers" for his insistence on military spit-and-polish, set about carrying out his meticulous plans for the first major amphibious operation in American history. He requested the construction of special surfboats for the landing and then left Washington for Mexico to meet with Taylor and assemble his army at a staging area on the sandy coral harbor of Lobos Island, some sixty-five miles to the southeast of Tampico. There forces deploying from the United States and most of Zachary Taylor's regulars were to gather for the forthcoming invasion.2

Scott assembled a very capable staff of topographical engineers. In all, twelve topogs served in various capacities under Old Fuss and Feathers during the campaign and in the postwar occupation period. They included Major William Turnbull, his chief topog; Captains George W. Hughes, Joseph E. Johnston, and John McClellan; 1st Lts. William H. Emory (now a brevet major), Charles N. Hagner, and Eliakim P. Scammon; and 2d Lts. George W. Derby, Edmund L. F. Hardcastle, George G. Meade (a brevet first lieutenant), Martin L. Smith, and George Thom. Hughes and Emory served as leaders of a volunteer regiment, an indication of their unusual versatility; Johnston switched over to the command of an elite infantry regiment; and Scammon would serve as one of General Scott's aides-de-camp.

Not all the topogs served throughout Scott's campaign and occupation period. Meade, Scammon, and Derby returned to the United States early, Hughes returned later, and other topogs arrived well after the march inland commenced. By the time Scott reached the outskirts of Mexico City only Turnbull, McClellan, Thom, and Hardcastle remained on his staff. Smith and Hagner arrived in the war zone later.

Major Turnbull already had a distinguished service career before reporting as Scott's chief topographer. He received his West Point commission as an artillery officer but ended up detailed to the Topographical Bureau and later joined the Corps. In 1831 and 1832 he surveyed railroad lines in Mississippi, and from 1832 to 1843 he designed and supervised the construction of an aqueduct spanning the Potomac River in Washington. The Aqueduct Bridge at Georgetown, built to carry canal traffic over the river to join another canal, had the distinction of being among the earliest important engineering accomplishments in the United States. Over the next two years Turnbull supervised the repair of the Potomac River bridge, and in 1844 moved on to supervise harbor improvements on Lake Ontario. On 7 December 1846, he received his orders to report to General Scott at Point Isabel.3

Captain Joseph E. Johnston, who like Robert E. Lee later became a Confederate general in the Civil War, received his commission from the Military Academy as an artillery officer. He resigned in 1837 to take up a private civil engineering practice and worked for the Topographical Bureau in Florida surveying depot and fortification sites, where he was attacked by Indians and received the first of his numerous wounds in combat. Johnston joined the Topographical Engineers in 1838 as a first lieutenant, and initially worked as a member of the United States and Texas Boundary Survey. His following assignments included Lake Erie harbor improvement work, a tour at the bureau, another tour in Florida (1841-1843), the Northern Boundary Survey (1843-1844), and the Coast Survey (1844-1846).4

Another former artillery officer Lieutenant Eliakim P. Scammon also transferred to the Topographical Engineers in 1838, one year after receiving his commission at West Point. He served his first year on active duty as an assistant professor of mathematics at the Military Academy before moving on to Florida as an assistant topographer. Scammon returned to the Topographical Bureau in 1840 for one year, then returned to West Point as an assistant professor of history, geography, and ethics. In 1846 he took over duties as the supervising engineer on the survey of New Bedford harbor, serving in that capacity until joining Scott's army.5

A recent Academy graduate, Lieutenant George W. Derby, immediately transferred from the Ordnance Corps to the Topographical Engineers. The top three or four graduates usually went into the Corps of Engineers, the next two to the Topographical Engineers, with the Ordnance Corps receiving the third ranking group of new officers. The mission of the Topographical Engineers especially appealed to Derby, which may have accounted for his high class standing, seventh in a class of fifty-nine. His high standing belied his nature, and he did not move on to high rank like many of his contemporaries. Instead, he would be remembered in later years for his boisterous "western" style of humor. Derby already had earned a

reputation at the Military Academy as a notorious practical joker, and it did not take long for him to become the topog's humorist. Before arriving in Mexico, he worked on the New Bedford harbor survey.6

Lieutenant Edmund L. E Hardcastle received his commission directly into the Topographical Engineers. A classmate of Derby's, Hardcastle ranked fifth in the class of 1846. He served for a short time with the Coast Survey before receiving his orders for Mexico. Hardcastle joined up with the irrepressible Derby for the long trip to their new assignment. The route they took, like Meade earlier, illustrates how several officers traveled to the war zone. They proceeded along the Ohio River by river boat, stopping long enough at Louisville to purchase a pair of fine Kentucky bluegrass horses, and continued down the Ohio and Mississippi to New Orleans. From there they went by steamer to Scott's temporary headquarters at Brazos Island. According to Derby, the two horses eventually ended up as food for the vultures in Mexico.7

By late December 1846 Scott had arrived in Mexico and detached most of Taylor's army. Almost all Taylor's regulars and an equal number of volunteers, about 8,000 in all, received instructions to assemble at Tampico and at the mouth of the Brazos River in Texas. From there they proceeded to the rendezvous at Lobos Island, the jumping off point for the amphibious operation at Vera Cruz. By February Captain John McClellan and Lieutenant George G. Meade, both veterans of Taylor's army, reported to Tampico to serve on General Patterson's staff. They reached Lobos Island the following month in time to board the ships heading toward Vera Cruz. Derby, who joined the general's staff at Brazos Island, recorded his impressions of camp life. After meeting General Scott he remarked, "The Major General is quite affable and frequently invites his staff to a dinner or a glass of wine, which they accept with astonishing readiness." Despite the severe living conditions and the changeable weather, Derby retained a positive outlook: "With a clear conscience, a strong man, a sharp saber, three pistols and a good horse I am good for a long leave of life even among the yellow bellies."8.

By early March 1847 Scott had gathered his army of nearly 14,000 men for the invasion. He organized his expeditionary force into two divisions of regulars commanded by Brig. Gens. William J. Worth and David E. Twiggs, and a volunteer division under Maj. Gen. Robert Patterson. Scott then resolved his transport difficulties as best he could. Concluding that his army and supplies were as complete as they ever would be, Scott boarded his army for the voyage to Vera Cruz.9

On the 6th, at a point southeast of Vera Cruz and near the island of Anton Lizardo, Scott's transport flotilla rendezvoused with Commodore David Conner's naval squadron. Scott, Conner, and their staffs boarded the Patricio, a captured Mexican steamer pressed into American service, to reconnoiter the landing area. The reconnaissance proceeded quietly until the party approached the coast to take a closer look at the town and its defenses. According to Meade the vessel came to within 1.25 miles of the city's castle when the Mexicans suddenly opened fire. Fortunately for the Americans the defenders missed the ship. Meade, on board at the time, surmised that only the Mexicans' poor aiming precluded a near disaster for the American leadership. "This operation," he later wrote, "I consider very foolish; for, having on board all the general officers of the army, one shot, hitting the vessel and disabling it, would have left us a floating target to the enemy, and might have been the means of breaking up the expedition." Such a shot would indeed have left the U.S. forces lying off shore virtually leaderless. Aboard the Patriczo were Scott's three division commanders (Twiggs, Worth, and Patterson), one of his brigade commanders (Gideon J. Pillow), the U.S. Army's Chief of Engineers and Scott's chief engineer (Colonel Joseph G. Totten), two of Totten's engineer staff (Robert E. Lee and Pierre G. T. Beauregard), and three topogs (Turnbull, Johnston, and Meade).10

Three days later the army, under the protection of the U.S. Navy's Home Squadron, came ashore in surfboats. The defenders

did not oppose the landings which took place three miles to the southeast of Vera Cruz. Within a week siege lines encircled the strongly fortified city. In order to keep his casualties to a minimum, Scott decided to resort to a heavy bombardment rather than a direct assault, thereby persuading the Mexican garrison to surrender. He asked the Navy to bring ashore their heavier guns manned by sailors. The combined artillery of ship and shore batteries then proceeded to bombard the city from sea and land. Old Fuss and Feathers also called upon the services of his two engineering staffs to reconnoiter the Mexican defenses, supervise the construction of the siege lines, and site artillery locations.11

Colonel Totten made sure his corps dominated the engineering support during the campaign to Mexico City. With outstanding young officers in the Corps of Engineers such as Lee, Beauregard, and George B. McClellan, the Chief of Engineers' goal of ensuring a brilliant accomplishment by his corps in the campaign became even more attainable. His recommendations carried significant weight, for not only was he a full colonel, thereby outranking Turnbull, but also chief of the Corps of Engineers. Neither did he overlook the former subordinate role of the Topographical Engineers. Totten did call for topographic help, but he made certain that the role of his own engineers predominated the scene.12

considerable amount of praise in the general's official dispatches. Old Fuss and Feathers, however, did not overlook his topogs, and they obtained due recognition throughout the campaign.13

Totten's corps also employed the only engineer troop organization during the Mexican War. Company A, Corps of Engineers, organized at West Point and composed of sappers, miners, and pontoniers (the forerunner of the Corps' combat engineers), deployed to northern Mexico in October 1846. The following month the unit, equipped with a unique rubber floating bridge, received orders to join Scott's army. During the siege of Vera Cruz the company's officers and enlisted men reconnoitered positions, laid out and supervised the construction of gun emplacements and trenches, and cut off the water supply to the city. Lieutenant George B. McClellan, one of the company's officers, would rise to flag rank during the Civil War and command a Union army. Company A engineers marched with Scott's army to Mexico City and participated in the series of battles leading to the capital. By contrast, the Corps of Topographical Engineers remained an officer-only corps without units of any kind.14

Meanwhile, the young and eager junior topogs also began their own record of commendable service at Vera Cruz. By the 28th Major Turnbull reported that Captains Hughes and Johnston had joined Worth's command manning the right flank of the siege lines; Captain McClellan and Lieutenant Meade had moved to the center with Patterson; and Turnbull himself had joined Twiggs on the left. Lieutenants Hardcastle and Derby, who had arrived on the 17th, began a survey of the besieging line of investment. During their work both lieutenants volunteered for duty with the artillery, for which they received due recognition. Colonel James Bankhead, the chief of artillery during the siege, reported: "I should not omit to mention two young officers of the corps of topographical engi-

neers, Lieutenants Derby arid Hardcastle, volunteered to serve in the trenches, and did serve well and gallantly for 24 hours."15

Official reports, however, sometimes tended to overplay actual deeds. When an artillery officer approached Bankhead to add his name to the report, another artillery officer reacted strongly and wrote,

I would cut my tongue out before I would allow it to commit so great an act of indelicacy. Colonel Bankhead will not, I hope, do it. He has already been induced to insert the names of two Topographical Engineers who were at one of the Batteries, mentioned because they volunteered, not because they did as much or more than others. The fact is, that at the Batteries there was but little room for individual distinction.16

Regardless of inflated battle reports, members of both engineering corps played important and dangerous roles during the siege, thereby contributing immeasurably to the fortified city's surrender. Using the time-honored procedures outlined 150 years earlier by Marshal Sebastian Le Prestre de Vauban, the French master of siege warfare, the engineers located positions and supervised the construction of the system of trench lines and fortified field artillery positions. The siege lines moved ever closer to the walls of the city and its defensive fire. In doing so the trench lines cut off and brought the enemy positions under close fire. In the end Scott's application of siegecraft and firepower brought swift victory and few casualties to the Americans, and by 27 March the defenders capitulated.17

of his many incredible feats in this campaign. One eyewitness recorded the entry of the two engineers into the city:

They were then distinguished young officers, intimate friends to each other, and their martial appearance as they rode, superbly mounted, to meet the Mexican officers, gave a general feeling of satisfaction to our army, that such representatives of the "North Americas" had been chosen for such an occasion.18

Although official reports cited the Topographical Engineers for meritorious service in the siege of Vera Cruz, there appeared to be more topogs present than believed necessary. Lieutenant Meade became a candidate for early release from the war zone. One consideration included his length of service, and Scott also believed that the young topog did not legitimately belong to his command. After conferring with Major Turnbull in late March, Old Fuss and Feathers ordered Meade's return to Washington.19

By April Meade reached New Orleans where he continued his outpouring of letters to his wife. In one letter he outlined the reasons for his return: "Major Turnbull said that I was unexpectedly with him, that I did not belong to his detail, and consequently he had officers enough without me." He added, "Again, I found myself at Vera Cruz a perfect cipher, the major, three captains, and one lieutenant I had over my head depriving me of any opportunity I might otherwise have of distinction."20

Meade felt that he departed the war zone with honorable service, but he still faced other concerns. Family finances particularly bothered him. This he noted, "has been a source of mortification to me greater than I can describe." Meade did seek advice from senior officers whether he should stay in Mexico, and they advised him to leave. Not sure whether leaving Mexico now meant he could be reunited with his family, the topog concluded:

The above were reasons influencing me; but I had nevertheless to struggle against my own personal inclination, which, I frankly confess, was to

remain, and against the fear that, when I report to Colonel Abert, he may either send me right back to General Taylor, or else send me to some out-of-the-way place, where my separation will be almost as complete from you, without all the advantages of being with an army in the field.21

Meade did not return to Mexico, and he did go on to conclude a successful military career. Upon his return to Philadelphia, the citizenry received him cordially and presented the topog with a beautiful and costly sword for his service in Mexico. He then served under Major Bache who had charge of constructing the Brandywine lighthouse in Delaware Bay. Meade went on to compile surveys of the Florida reefs for the Topographical Bureau. In 1849 he received orders to report to Florida to survey fortification sites during renewed hostilities with the Seminole Indians. He returned the same year to continue his work under Major Bache. In 1851 he again reported to Florida to supervise lighthouse construction in the keys. A captain by 1856, Meade moved on the following year to take over the Great Lakes survey, which he directed with extreme efficiency until 1861. Soon after the first guns sounded in the Civil War he received an appointment as brigadier general of volunteers. Within a few years he found himself in command of Union forces at Gettysburg. His observations of field operations during the Mexican War, his appraisal of generals such as Taylor, and his preparation of battlefield maps undoubtedly undergirded the decisions he would make during one of the nation's most fateful battles.22

After capturing Vera Cruz and establishing the port city as his base of supply, Scott quickly moved inland toward Mexico City. He also grew concerned over the impending approach of the dreaded yellow fever season. Especially prevalent along the lowlands of the coast, the disease could do more harm to his army than the enemy.

This spurred Old Fuss and Feathers to reach the more healthful higher altitude as soon as possible, thereby ensuring better prospects for the health of his men. Jalapa, a city in the highlands some seventy-four miles inland along the National Highway, became the next objective. Santa Anna, however, had raised another army and on 5 April reached the city first.23

Santa Anna decided to make a stand at Cerro Gordo, a rocky defile twenty-four miles to the east. Convinced that the Americans, with their artillery and wagon train, could only advance along the National Highway, the Mexican leader began to dig in his force of 12,000 men. They sited their cannons on the summits of a mountain called El Telegrafo and along the neighboring hills. Advised by his own engineers, the wily Santa Anna made most of the excellent natural defense positions afforded by the rocky terrain overlooking the road.24

By this time Scott had begun to move his army into the Sierra Madre Mountains. Twiggs led the march to Jalapa, and by 11 April his division encamped near the Plan del Rio, not far from Cerro Gordo. The following morning an advance party of his dragoons drew fire and the two armies prepared to do battle. Old Fuss and Feathers pitched his camp on the 14th and immediately ordered a careful reconnaissance of the Mexican positions. He soon realized that a frontal assault would be suicidal, and directed his engineers under Captain Robert E. Lee to check out the Mexican left flank.25

Lee did find a way to outflank the defenders, and Scott executed the first of several flanking movements in his march to Mexico City to decisively defeat his foe. After going out on several dangerous reconnaissance patrols, Lee found a way to traverse the rough terrain to the right of El Telegrafo. This enabled the Americans to bypass the main defensive positions and strike the Mexican rear. Troops improved the path, other soldiers manhandled artillery pieces up and down slopes, and an assault force seized an adjacent summit. On the morning of the 18th the Americans took El Telegrafo after a sharp fight. Just as the defenders there began to fall back to Cerro Gordo, the flanking force struck. The Mexi-

cans were completely routed, losing 1,000 killed or wounded and 3,000 prisoners. Scott lost only 64 killed and 353 wounded. An impressive quantity of guns and small arms fell into American hands- to say nothing of Santa Anna's spare wooden leg. The fleeing Mexican army virtually ceased to exist.26

Lee received due recognition after the battle, and several topogs also received credit for gallantry. Now serving with the regiment of voltigeurs (an elite mobile cavalry like force consisting of dragoons, infantry, and artillery), Joseph E. Johnston began his combat duties with distinction. The voltigeurs wore a distinctive grey instead of the customary blue uniform, received training as expert skirmishers, and operated forward of the main force. Considered an honor regardless of the dangers, service with the voltigeurs became popular, and many soldiers volunteered to join. Johnston usually placed himself out in front during the attack, and his audacity in combat made him a magnet for bullets. The wounds he received at Cerro Gordo were the first of many to follow in the Mexican War campaign. A friend later recalled the topog's eagerness to gain information about the Mexican defenses:

We had been halted in the timber, just out of sight of the enemy, some twenty minutes, when we heard the rattle of musketry, and a few minutes later the order came "fall back to the right and left of the road" to let the bearers of Captain Johnston pass by. He had received two severe wounds while making a daring Reconnaissance, and was borne back to Plan Del Rio.27

Although Johnston now served with the voltigeurs, he continued to accomplish topographical duties on a voluntary basis. On this occasion he brought back important information revealing Mexican capability to sweep the road with artillery fire. Already holding the rank of lieutenant colonel of the Voltigeur Regiment, Johnston first gained a brevet promotion to major and then to colonel for gallant and meritorious conduct and for wounds received in his reconnaissance.28

While Lee and other engineers reconnoitered the Mexican left flank on the 15th, Lieutenant Derby accomplished the same mission along the right flank. Accompanied by a single escort, the topog pushed through the chaparral and cactus for 4.5 miles until reaching a good vantage point to observe the enemy positions. He calculated the number of troops and artillery and mapped the locations of the Mexican forces and the terrain. The following morning Inspector General Ethan Allen Hitchcock wrote, "Just returned to my tent from a long conference at the General's hut. Reconnoitering parties all present. Lee, Derby, and others have made the boldest examinations and have given a great deal of information. Enemy very strong on main road." Thus, along with Lee, Derby provided Scott with valuable information.29

The following day Derby received orders from Major Turnbull to accompany Twiggs' division to outflank the Mexican defenders. Lee oversaw the initial construction of a path for Twiggs' column and then guided the flanking forces while Derby stayed with the pioneers. "Suddenly," Derby later recalled, "we were surprised by a rapid fire from the first hill, which from a slight sprinkle became a perfect hail storm." Colonel William S. Harney's brigade then attacked up the hill (Atalaya), and Derby joined in the assault. Derby continued his account:

About half way up, my horse was shot and fell under me with a ball through his hind leg and I had to tie him up to a tree and foot it up the rest of the way which was far preferable as the hill was so steep it was impossible to ride. We drove the Mexicans from the 1st to the 2nd hill, racing after them and yelling like wild Indians, which last scared them as much as the firing .... I shot one fellow with a pistol who was about firing. He fell and begged for his life. I told him to lay still and nobody would touch him and went on. But when I came back after the fight to help him I found somebody had killed him. He was some sort of an officer and I took his sword and I got it [sic] somewhere now . . . . We occupied this hill that night and lay on our blankets. The Mexicans firing grape shot and canister over us occasionally but with very little effect.30

Derby also participated in the attack up El Telegrafo on the 18th. While the indefatigable Lee guided Scott's flanking forces farther around Santa Anna's defenses, Harney's brigade shouted a

great hurrah and charged down the Atalaya, across the hollow, and then up El Telegrafo. Derby accompanied the charge and later described the assault:

Down we went through the whistling balls and crashing grape, men dropping here and there, the wounded groaning, but nobody scared, and with a tremendous yell we gained the ravine and commenced the ascent of Sierra Guardia [Cerro Gordo]. A fire, close, heavy and continued, from 1800 muskets was opened on us, but the ascent was so extremely precipitous that it afforded us protection, for most of the balls passed over our heads. The whistling was terrific, the air seemed alive with balls, but we went on cheering and returning the fire now and then, when we stopped for an instant to rest. At last we came to the highest crest within ten rods of their first breastwork. We gave one fire, then Colonel Harney shouted .... Away we went. The Mexicans saw us coming. Nothing could withstand such a charge, they gave one fire and ran. We followed, clambered up over the breastwork, chased them from the tower, over the hill, turned their own pieces on them, and the Sierra Guardia was ours. Up went the American flag and down came the Mexican.31

Derby also gave an account of his wound and a somewhat humorous and probably apocryphal encounter with Old Fuss and Feathers. The topog had been directing fire on the retreating Mexicans when suddenly a bullet struck him in the left hip. General Scott, later riding by the battlefield, saw the wounded topog and supposedly exclaimed, "My God Darby, you're wounded!" Derby then replied using a similar English pronunciation, "Yes, General Scatt." The general bristled, "My name is Scott, not Scatt!" The wounded lieutenant retorted, "And my name is Derby, not Darby." Derby, however, wrote of the general's visits to him in the hospital, when Scott expressed his sympathy and his pride in the young topographical engineer. The official dispatches mentioned the topog's deeds at Cerro Gordo, and he subsequently received a promotion to brevet first lieutenant.32

The partitions of the rooms were of reeds, wattled together, so that conversations could be heard from one room to the other. John Phoenix

Derby was an incessant talker and uttered a stream of coarse wit, to the great disgust of Joe Johnston, who endured it in silence, till one day he heard Derby order his servant to capture a kid out of a flock of goats passing on down, when he broke out, "If you dare to do that, I'll have you court martialed and cashiered or shot."33

After Cerro Gordo, Major Turnbull dutifully reported the details of the battle and the latest activities of his shrunken staff to Colonel Abert. By then Meade had departed, Johnston had joined the voltigeurs, Derby had returned home wounded, and Hughes and Scammon (Scammon served as Scott's aide until May) had returned to the States because of illness. Suddenly the large and apparently overstrength topog staff had dwindled down to Turnbull, John McClellan, and Hardcastle. Appraised of this situation, Colonel Abert issued instructions for Lieutenants Hagner, Martin L. Smith, and Thom to report to Scott's command.34

The wounded Derby returned to the United States, and the rest of his life turned out to be a mixture of humor and tragedy. He served for awhile at the Topographical Bureau. Some truth exists of the tale that Colonel Abert transferred him later to a California mapping and exploration project in order to remove the lieutenant from the proximity of his daughter. The wounded war hero who dressed in an unusually bright uniform, handsome, young, and robust, undoubtedly appealed to Abert's young, marriageable daughter.35

The transfer to California turned out to be a pivotal point in Derby's life. There he launched a literary career under the name John Phoenix. He satirized the Army, American culture, and even the Pacific railroad surveys, all while remaining a dedicated Topographical Engineer. Between 1848 and 1854 he served in Minnesota, Texas, and twice in California. In 1850 to 1851 he conducted a notable reconnaissance on the lower Colorado River. In 1855 he moved up to Oregon and Washington to build roads; a year later he worked with the Coast Survey; and, between 1857 to 1859 he con-

structed lighthouses in the Southeast. After fourteen years' service he reached his highest rank as a captain. Because of the effects of sunstroke and failing eyesight, he was placed on sick leave. He died on 15 May 1861, having made material contributions to the work of the Topographical Engineers.36

Lieutenant George Thom reported to Mexico that summer, but he like Scammon ended up as an aide de camp. Commissioned directly at West Point into the Topographical Engineers in 1839, Thom started out as an assistant on the surveys on the northern boundary. The following year he worked on the Delaware harbor improvements project for a short period before returning to the boundary survey. There he received orders to report to Scott in Mexico. After his arrival Thom served his tour as Brig. Gen. Franklin Pierce's aide and saw some action in skirmishes between 1 July and 6 August 1847. By late October he became ill and returned to the United States where he continued to serve as a topog and later in the Corps of Engineers. He concluded his military career as a colonel after forty-four years of uninterrupted service.37

After Cerro Gordo the way now appeared open to Mexico City, some 170 miles to the west. Worth's division took the lead, and without any difficulty his troops took Perote on 22 April and Puebla in mid-May. By then Scott had decided to release some 3,700 men- the bulk of his volunteer force- before their enlistments came to an end. (Only a handful agreed to reenlist for the duration of the war.) Always thinking of the welfare of his men, Old Fuss and Feathers wanted to minimize the danger that they might catch yellow fever as they moved back through Vera Cruz. He also realized that his twelve-month enlistees caused disciplinary problems and might mistreat the Mexican population. Guerrilla

activity had increased along his supply route, and he wanted to maintain good relations with the civilian population. By now he depended almost totally on the local populace to supply his army.38

Scott then moved on with the bulk of his force to join Worth at Puebla. Arriving in late May, he pulled in the garrisons from Jalapa and Perote. At the risk of cutting off his connection with the coast along his supply route, Scott instead chose to reinforce his small command. He decided that his command must take its chances and, in the midst of a hostile nation, live off the land. The departure of the volunteers, however, in early June left him with only a little more than 7,000 men. Figuring the army still too small to move on to Mexico City, Old Fuss and Feathers elected to await reinforcements and developments in peace negotiations before resuming the march.39

During their three-month stay in Puebla, Scott's engineers collected and studied all the available maps of the approaches to Mexico City. Turnbull and Lee gathered information from natives and travelers and then penciled their findings on a map. Later, when they verified the entries, Turnbull and Lee inked over their penciled marks. Scott examined their map almost daily.40

By 7 August 1847 Scott, his force now slightly under 11,000 healthy and sick soldiers, renewed the march to Mexico City. Twiggs' division led the way, with divisions commanded by Worth, Quitman, and Pillow following at one day intervals. Leaving only a small garrison behind at Puebla to protect his sick, Scott's columns moved farther inland.41

These defenses took advantage of several natural obstacles around Mexico City, particularly the swamps on either side of the roads and causeways leading into the city.42

By the 11th Twiggs' division reached Ayolta, some fifteen miles from Mexico City, and Scott himself arrived later that day to plan his next move. While Twiggs' troops encamped and the other divisions moved up into supporting positions, the engineers helped by the topogs reconnoitered the approaches toward the city. Besides the indefatigable Lee, other Corps of Engineers officers included Captain James L. Mason; 1st Lts. Beauregard, Zealous B. Tower, and Isaac I. Stevens; and 2d Lts. George B. McClellan, Gustavus W. Smith, and John G. Foster. Turnbull and Hardcastle accompanied their colleagues as necessary and prepared maps.43

These reconnaissance patrols provided considerable invaluable information which helped Scott to formulate a plan to outmaneuver Santa Anna's strong defenses. On the 12th Lee, Mason, and Stevens reported the presence of strongly fortified positions to the northwest at the El Penon heights overlooking the National Highway. This information, coupled with other reconnaissance reports, persuaded Scott to find another route and to outflank the Mexican stronghold. On the 13th Lieutenants Beauregard and McClellan made a reconnaissance to Mexicalcingo, just a few miles to the south of Mexico City. There they met Lee and Tower, who moved along separate routes farther south. Lee and Beauregard then relayed information that a rough road farther south around Lake Chalco could carry the artillery and wagon train toward San Augustin. By following this route an American force could outflank the Mexican positions at both El Penon and Mexicalcingo. A later reconnaissance by Colonel James Duncan, Worth's artillery chief, confirmed Scott's decision to move in that direction.44

On 15 August Scott issued orders to move south around the lake, thereby striking the capital directly from the south. Worth's

force set out while Twiggs, remaining at Ayolta, began operations to conduct a secondary attack to deceive the enemy. Worth occupied San Augustin on the 18th, only nine miles directly south of Mexico City. Three miles to the north near the hacienda of San Antonio, an engineer reconnaissance party, which included Turnbull and Hardcastle and their escort, drew a hail of Mexican fire. A direct assault toward strongly defended San Antonio appeared to be ruled out. Here too the terrain appeared to create an almost impossible barrier for even a flanking movement. A bog to the right and the Pedregal, an extensive lava field interwoven with deep cuts, fissures, and ridges, presented a unique natural barrier to the Americans' left.45

While Old Fuss and Feathers considered his next move, Santa Anna shifted the bulk of his forces between Contreras and Churubusco. Scott considered attacking west of San Antonio via the San Angel road, but on the 18th Lee and Beauregard brought back information suggesting the feasibility for a route through the Pedregal. While the engineers searched the western portion of the lava bed for a crossing, their escort clashed with Mexican pickets. This implied the existence of a path. The American scouting party also found a road that dwindled into a mule path and then disappeared amidst a jagged sea of lava. From this point, however, Lee could see the San Angel road only a mile and a half to the west. With this news Scott decided to open a road across the Pedregal. Such a passage would make possible the deployment of an artillery train to an enfilading position overlooking the San Antonio defenses. Lee then proceeded to supervise a 500-man work party drawn from Pillow's division to carve a passage through the lava.46

On the 19th the Mexicans detected the American road-building operation, and a clash lead to the bitter two-day Battle of Contreras (which really took place at Padierna). Without Scott's knowl-

edge or approval his subordinate commanders launched an attack which drew more Mexican forces into the battle. Fortunately for the Americans, Santa Anna's commander on the scene ignored an opportunity to crush a large part of Scott's force between two appreciably larger forces. Evening brought a heavy, cold rain. Again, thanks to Lieutenant Tower, the engineers found a way around the Mexicans' rear. That evening Lee, moving through the rugged lava fields and guided only by intermittent lightning flashes, carried word back to Scott of a new plan to encircle the enemy. Although exhausted, Lee guided additional troops to the battle in the early hours of the following day, thus allowing the flanking forces to rout the defenders. Ulysses S. Grant, then a lieutenant in the infantry, recalled, "This affair, like that of Cerro Gordo, was an engagement in which the officers of the Engineer Corps won special distinction. In fact, in both cases, tasks which seemed difficult at first sight were made easier for the troops that had to execute them than they would have been on a ordinary field."47

As the Mexican troops fell back in disorder, Scott directed an immediate thrust from his positions at Padierna and San Augustin toward Churubusco. Lee, moving with the advance element of Twiggs' division, guided an attacking force north of the town to Portales. To the south Mason, helped by Hardcastle, guided a brigade of Worth's division through the eastern fringe of the Pedregal around the defenses of San Antonio. Another Engineer, Stevens, relayed information from the west, and Scott ordered Twiggs' to attack the partially fortified San Mateo Convent Church just to the west of Churubusco. For a while inspired Mexican forces stopped the American advance at the convent. Just south of town at a fortified bridge the defenders also halted Worth's division coming up from the south. Repeated attacks by Worth's soldiers took the bridge in hand-to-hand fighting, and the convent's defenders surrendered under heavy bombardment. By the afternoon of the 20th both of Scott's forces met on the road north of town. The battle turned into a pursuit as the dispirited Mexican

soldiers fled northward to Mexico City. That evening Santa Anna sent word to Scott to discuss armistice terms.48

Scott could have continued the pursuit into the city, but he decided to pause, much to the consternation of his officers and men. Old Fuss and Feathers preferred to rest and regain control of his troops, hoping that the Mexicans might take the opportunity to accept surrender terms. In only two days his army had fought two hard battles. Several defensive works remained outside the city, and he believed taking the capital too formidable a task for a quick and easy success. American casualties in the two battles were also a point of concern- nearly 1,000 men killed or wounded out of a force of 8,500. Although he had conducted a brilliant campaign, the American commander remained well aware of his small army's vulnerability in the midst of the enemy's country.49

Under these circumstances Scott decided to accept the Mexican leader's armistice proposal on 24 August. Although Santa Anna lost almost a third of his force, roughly 10,000 men, in the two recent actions (more men than Scott had in his army), he could still call upon a willing pool of manpower. The respite restored Santa Anna's confidence, and he prepared to resume fighting. "During the armistice," Beauregard wrote, "no reconnaissance was permitted by the Commander-in-Chief, although it was a notorious fact that the enemy was violating it day and night." Seeing that the Mexicans were rapidly strengthening their remaining defenses and that negotiations were not accomplishing anything, Scott called off the armistice on 6 September. Two days later the Americans resumed the attack.50

By the 7th Scott's engineers resumed reconnaissance operations. The general's attention now turned toward El Molino del Rey, a mass of heavy stone buildings housing a mill and a foundry just to

the west of the fortress of Chapultepec. About 500 meters farther west Mexican engineers constructed bastioned earthworks around another massive building, the Casa de Mata. Captain Mason helped by Hardcastle hastily reconnoitered the Mexican defenses. Scott, who also heard that cannon were being made at the foundry, ordered Worth's division to conduct a night raid on the suspected factory. Worth, however, elected to hold off the attack until morning, and the raid turned into one of the bloodiest battles of the war. Fighting raged from dawn to dusk. Persistent assaults seized the buildings and the nearby Casa de Mata only after the attacking American troops suffered some of the heaviest casualties of the war. During the battle Turnbull and Hardcastle and their engineer counterparts continued their scouting duties and carried dispatches.51

Scott turned to his next objective, the rocky and fortified hill of Chapultepec towering over two main causeways leading into the city. By now Scott's command had dwindled to about 8,000 men opposing some 15,000 less experienced troops under Santa Anna. During the short pause, the engineers continued to go about their assigned tasks. They reconnoitered enemy defenses, supervised the construction of artillery positions, and advised Old Fuss and Feathers. On the 12th a heavy artillery bombardment began to rain down throughout the day on the steep hill and its old castle and the buildings of the Mexican Military Academy.52

The barrage resumed at dawn the following day, and the assault by Scott's four divisions got under way. While Twiggs' division conducted a diversionary attack on the city's southern causeways, the other three divisions participated in the main attack from the west. At 0800 the bombardment momentarily ceased. The regulars of Pillow's division with some help from Worth stormed up the slope from the west, while Quitman's division of volunteers and a small force of U.S. Marines advanced up a causeway south of the

hill. Despite some mistakes, including a lack of scaling ladders, the Americans seized the castle after a brief and bitter struggle.53

Without pausing the Americans moved on into the city. Quitman's troops, sensing total victory, immediately pursued the retreating enemy along the paved causeway to the Belem Gate. At the same time Worth's men moved northeast to the San Cosme Gate. The causeways canalized the advancing soldiers, and the Mexican defenders poured down fire on the densely packed columns. Most of the American losses that day- 130 killed, 703 wounded, and 29 missing- took place along the causeways. The attackers, however, did not hesitate, and by nightfall both gates were in American hands.54

Before and during the battle the engineers continued to reconnoiter the southern and southwestern approaches to Mexico City. At a conference on the 11th Beauregard advised Scott that the attack on the capital should be from the west and that Chapultepec Hill should be seized before entering the city. To divert the Mexicans' attention, he also recommended a secondary attack south of Mexico City. This plan differed from recommendations submitted by other members of the general's staff. They advocated the main attack from the south. Earlier, however, Scott had considered a move similar to that recommended by Beauregard, and the general adopted that course of action.55

Recovered from his wounds at Cerro Gordo, former topog Lt. Col. Joseph E. Johnston led his voltigeurs in the assault on Chapultepec. As one of Pillow's three attacking columns, the elite infantry unit advanced along the southern walls of Molino del Rey to help seize the base of Chapultepec before the Mexicans could set off their land mines. They then pushed on up the slope to the base of the massive retaining wall of the fortress, where they had to wait for the ladders. When the ladders arrived, the voltigeurs scaled the walls and were among the first Americans to raise their regimental colors over Chapultepec. This time Johnston received several light wounds.56

Beauregard accompanied Johnston in the assault and later attested to the topog's personal bravery. Noting that, "there are, if

any, few better or braver officers," Beauregard also recalled an exchange of words he had with Johnston during the assault on the Mexican fortification:

I turned round and cried out to him as loud as I could, until I had drawn his attention (for the firing of the infantry and artillery, the hissing of the balls, etc. was perfectly deafening) and knowing the effect which such a demonstration under those would create in our favor, I said to him, holding at the time a loaded rifle in my hand, which I was about to fire, "Colonel, what will you bet on this shot?" He quickly replied, "A picayune, payable in the City of Mexico." (or he may have said: "Drinks in the City of Mexico," I cannot now recollect which), I then took deliberate aim, fired and cried to him, "you have lost, you will have to pay it."57

Scott's army cautiously entered the city the following morning. Exhausted and anticipating a bloody battle in the streets, the troops, much to their relief, discovered that Santa Anna had evacuated the city. Except for some intense guerrilla activity, and a 28-day siege of the Puebla garrison in September and October, the war had substantially ended. In the meantime, the United States pressed for peace negotiations, and the Mexicans tried to form a new government.

From Vera Cruz to Mexico City, General Scott and his senior commanders frequently cited the meritorious and gallant services of their two engineering corps. Publicity focused on the larger Corps of Engineers because of the exceptional and heroic acts its officers accomplished, especially the "gallant and indefatigable Lee." Only in such exceptional cases, however, were any details of specific accomplishments provided. General Patterson simply commended Captain McClellan and Lieutenant Meade for their services at Vera Cruz. General Scott mentioned Johnston and Derby for their gallant conduct at Cerro Gordo, but provided no other details. Scott's report referred to the contributions of Turnbull, McClellan, and Hardcastle after Contreras and Churubusco, and Worth underscored Hardcastle's "zeal, intelligence, and gallantry, in his particular department, as also in combat." Twiggs mentioned McClellan in his report. After Molino del Rey, Worth again

commended Hardcastle. Scott concluded his report on the seizure of Mexico City by noting the meritorious services of Turnbull and Hardcastle, and Twiggs again mentioned McClellan. General Pillow in his report cited Johnston and his voltigeurs for their part in taking Chapultepec.58

During this campaign, the Topographical Engineers also received several brevet promotions. Turnbull became brevet lieutenant colonel and later received a promotion to brevet colonel for gallant and meritorious service at Contreras , Churubusco, and Chapultepec. Johnston ended his tour in Mexico as a brevet colonel, and McClellan departed as a brevet lieutenant colonel. Hardcastle received brevet promotions to first lieutenant and captain after the campaigns around Mexico City. A latecomer, 2d Lt. Martin L. Smith received a brevet promotion to first lieutenant for meritorious service after the occupation of Mexico City.59

Meanwhile, Hughes and Emory had returned to Mexico as members of a volunteer infantry regiment. After serving with General Wool's army during the march into northern Mexico, Hughes returned to Washington in the spring of 1847. By late June President Polk promoted him to a lieutenant colonel of volunteers with orders to assume command of a volunteer regiment with troops recruited from Maryland and the District of Columbia. On 23 July Hughes directed the advance element under Major John R. Kenly to proceed to Vera Cruz.60

been put in command of a large task force. Besides the five companies of his regiment, he also took charge of two companies of infantry from other regiments, two squadrons of Louisiana mounted troops, and an artillery battery.61

It did not take long for Hughes to see action. Not far from Jalapa the volunteers ran into guerrilla forces, and by the 9th the column routed the Mexicans from a strongly fortified position blocking the highway. Kenly later wrote, "great praise is due for the admirable manner in which he [Hughes] had succeeded in the attack and capture of the National Bridge, which during the whole war had been a thorn in our flanks, and had never before been held by an American army."62

For the next two months Hughes' regiment accomplished its security mission along its assigned section of the road. Despite Scott's capture of the capital, Mexican irregulars continued to harass American traffic along the National Highway. The former topog arranged a meeting with guerrilla leaders and nearly came to an agreement, but he received orders to move inland to reinforce Scott. This left the commander of the relieving unit to conclude negotiations. On 5 November Hughes proceeded west and temporarily encamped his regiment near Jalapa, but on the 22d he received orders to move his regiment back to Jalapa and to garrison the town. There he received an appointment as military governor of the province.63

Hughes accomplished his duties as military governor with tact and diplomacy, maintaining cordial relations with the Mexicans. When necessary, however, he kept order by employing stern measures. As usual most of the problems resulted from improper behavior on the part of American soldiers. To placate the local populace, Hughes issued a proclamation of general amnesty on 30 November. In general, the Americans and Mexicans mixed freely in Jalapa, and the military governor developed cordial relations with the leading clergymen in the community, especially the Franciscans. His friendship with the priests, however, resulted in some

resentment on the part of Mexican officials in the capital. Later these officials banished the head of the order from Mexico City.64

Hughes also had an interesting involvement with Santa Anna. In early 1848 Santa Anna received permission from the United States to depart the country. His aides then asked Hughes to provide an escort for Santa Anna's party to visit one of his estates in order to make final preparations for his departure. Hughes handled this sensitive affair with his usual tact. In a letter requesting General Twiggs' permission, Hughes concluded, "I think you will regard the matter as I do; that it is as fraught with the highest importance to our government in the present State of affairs as he is the great obstacle to the arrangement of a Peace." Hughes emphasized the importance of Santa Anna's safety and eagerly assumed responsibility to meet this request in order to get the ex-dictator out of Mexico.65

When Santa Anna reached Perote in late March Hughes entertained him and escorted the former Mexican leader and his entourage to the hacienda. Some tension occurred along the road when the Mexicans and their American escort had to pass through a regiment of Texas Rangers. The escort, however, surrounded Santa Anna and his party and pushed through the bitter Texans without incident. Santa Anna reciprocated Hughes' kindness by inviting the topog and several of his officers to visit the hacienda, where a rather pleasant gathering took place. A few days later Santa Anna safely departed the country.66

While Hughes was visiting Mexico City in April, Lt. Col. William H. Emory reported for duty with the regiment. After preparing his report and map of Kearny's expedition to California, the topog received an appointment to Hughes' volunteer regiment as second-in-command. Emory applied his usual thorough approach to this

new and different job. Major Kenly aptly summarized the topog's contributions to the regiment:

This gallant and accomplished officer gave to the regiment the benefit of his skill and experience by zealous efforts in its drill and instruction. He was successful in adding increased efficiency to the command and in winning the confidence and esteem of us all. From first to last, my relations with him, as they had been with Colonel Hughes, were intimate and friendly. He remained with the regiment until its final discharge at Pittsburgh, Pennsylvania.67

In submitting the Topographical Bureau's annual report to the Secretary of War, Colonel Abert praised Hughes' performance as a commander and military governor. The colonel wrote, "His march from Vera Cruz to Jalapa is spoken of as one of great merit and severe trial, in which he on several occasions encountered and beat the enemy." The chief topog concluded, "his highly judicious, energetic, prompt, and well judged measures, [were] mainly instrumental in keeping that extensive district quiet as well as the whole road from thence to Vera Cruz." On 16 June, following the ratification of the peace treaty between the two countries, the regiment departed Jalapa and marched to Vera Cruz. There the unit embarked on the 22d for the return voyage to the United States.68

During the march inland, the Topographical Engineers deferred any detailed reconnaissance patrols and mapping of the adjoining countryside because of operational concerns. The topogs also submitted more straightforward reports in comparison to the adventurous and interesting literary styles of Fremont, Emory, Abert, and to some degree even Hughes. Major Turnbull's reports were limited in scope, generally confining his remarks to the progress of the advancing army and the status of his officers.69

1848, when American forces withdrew, Turnbull's small staff mapped the region around Mexico City, reconnoitered the key roads, and prepared battle maps to accompany reports of the campaign. In October 1847 Turnbull reported to Colonel Abert that Lieutenants Hardcastle and Smith had set off to reconnoiter the area around Mexico City before preparing a map of the region. Lieutenant Charles N. Hagner traced the road between Mexico City and Taluca. He also forwarded copies of captured maps that included information on Acapulco, Vera Cruz, and various roads. McClellan helped to prepare the campaign maps of the battles around Mexico City before departing the command in December 1847. Turnbull returned to the United States in March 1848, and Lieutenants Hardcastle and Martin L. Smith remained to complete surveys for their map of the Mexico City region.70

One of the topogs' primary tasks required the preparation of detailed maps to accompany campaign and battle reports for submission to the War Department. In turn, the War Department prepared the maps and reports for publication in the Congressional Series. Turnbull and McClellan prepared the map of the Battle of Cerro Gordo, and Hardcastle did the same for reports submitted by General Worth. In August and September 1847 Turnbull, McClellan, and Hardcastle prepared the detailed maps depicting the battles for Mexico City. Considered the definitive depiction of terrain and unit dispositions, the maps later proved to be a valuable reference for historians researching the war.71

Hardcastle and Smith also prepared an excellent map of the Valley of Mexico. They accomplished their survey by triangulation and hand compasses, and the cartography accurately depicted the region as it appeared in 1848. The two lieutenants also recognized that they had the advantage of following in the earlier footsteps of Alexander von Humboldt, the noted German naturalist and explorer. Hardcastle and Smith noted a slight difference in mapping the lakes outside of Mexico City but believed that these lakes had changed over the years. Hardcastle also measured the distance between Mexico City and Vera Cruz by attaching an odometer to a

wagon wheel. He found minor differences between his plottings and those of von Humbolt. After Turnbull prepared campaign maps to accompany battle reports, the two topogs incorporated his survey of the area south of the city into their map of the region. Congress later published the report and map. Unfortunately, the narrative report did not provide the interesting features commonly included in reports by Fremont, Emory, and Abert. Instead, it dealt primarily with details of military campaigns and included some geographic descriptions.72

Antiexpansionists in the Senate, however, viewed the map's publication solely from a negative political point of view. Much of the work accomplished by the Topographical Engineers in mapping regions of Mexico became suspect. Some members of Congress grew suspicious that securing such geographic information could be part of an administration plot to annex all Mexico.73

The topogs serving in Scott's army continued to lead productive military and civilian careers. Upon returning to the United States, Hughes reverted from brevet lieutenant colonel back to a captain in the Topographical Engineers. He worked on a railroad survey across the Isthmus of Panama and planned to write a complete report of the operations of his volunteer regiment, but he resigned in 1851. As a civilian he entered the railroad business and later served in the House of Representatives as a delegate from Maryland. He also devoted himself to agricultural pursuits on his estate in Maryland, where he died in 1871.74

Commission in the Southwest. In 1855 Emory transferred to the cavalry and rose to the rank of major general of volunteers in the Union Army during the Civil War. He retired in 1876 with a regular rank of brigadier general and died in 1877.75

Johnston, of course, became a prominent Confederate general during the Civil War. Like the other Mexican War veteran officers he reverted to his regular rank of captain. He resumed work as a topog in Texas and later worked on projects to improve western rivers. He transferred to the Cavalry in 1855 and rose to lieutenant colonel. At the outbreak of the Civil War, Johnston, by then a brigadier general, offered his services to Virginia and the Confederacy. He commanded troops at Bull Run in 1861, and later served in the Peninsula Campaign. Upon recovering from wounds suffered at Seven Pines, the former topog took charge of Confederate forces farther west and participated in the Vicksburg and Atlanta campaigns. Although Johnston never directly lost a battle in the war, his earlier tendency to take risks in battle ended after Seven Pines. After the war he went into business, and in 1878 served one term in Congress. He died in Washington in 1891.76

Turnbull remained with the topogs for almost the remainder of his life. He returned from the wax to take over construction of the Customs House in New Orleans. In 1850 he assumed supervision of lighthouse construction, and two years later prepared engineer studies for bridging the Susquehanna River. The following year he completed studies to build a canal across the Falls of the Ohio River. Between 1853 to 1856 he supervised harbor improvements on the Great Lakes followed by similar work at Cape Fear, North Carolina. He died in 1857.77

John McClellan also spent his remaining years working for the Corps. He reverted to captain after the war, and between 1849 to 1851 served on the United States-Mexican boundary survey. In 1853 he began working on a project to improve the Tennessee River; however, he suddenly died the following year.78

Hardcastle stayed on in the Topographical Engineers for a few years before switching to a business and political career. After the

war he helped Emory on the United States-Mexican boundary survey until 1852. For the next four years he served on the Lighthouse Board, resigning his commission in 1856. By 1868 he became president of the Maryland and Delaware Railroad Company and also served in the Maryland House of Delegates between 1870 and 1878. He lived until 1899.79

Martin L. Smith stayed in the Army, and like Johnston served in the Confederate Army during the Civil War. After leaving the valley of Mexico City he surveyed roads in Texas and worked on the boundary survey. Between 1853 to 1854 Smith surveyed a ship canal across Florida. In 1857 he continued his topographical engineer work with the Coast Survey. At the outbreak of the Civil War he resigned his commission and rose to the rank of major general in the Confederate Army. He died in 1866.80

Throughout his campaign from Vera Cruz to Mexico City, General Scott increasingly relied on the services of his two engineering staffs. Their joint duties involved directing assault forces to key objectives and accomplishing dangerous reconnaissance missions. Under such circumstances, separating the actions of the two engineer corps in Scott's command became difficult. From the standpoint of publicity, the larger Corps of Engineers staff under Colonel Totten appeared to get credit for most of the engineering accomplishments. In any case, Old Fuss and Feathers effectively used both engineering corps to help him develop his strategy and tactics. In preparing for his march to Mexico City, Scott ordered his engineers to make a thorough reconnaissance of the enemy's positions and the surrounding terrain. The Commanding General began to rely so heavily upon his engineers that he hardly selected a route or issued an attack order without some form of reconnaissance. His engineers became experts at pointing out artillery batteries and vulnerable points in the enemy's lines. In one battle after another Scott executed brilliant flanking movements over terrain that the Mexicans had considered impossible for such maneuvers.81

Working with the armies in the field and their indefatigable engineer colleagues, the topogs proved their mettle. Matthew F. Steele in his classic work, American Campaigns, noted that the only attack made without an engineer reconnaissance "was Worth's impetuous assault of the bridge-head at Churubusco. Truly did the Military Academy repay its cost to the Nation with the work of these young graduates in this single campaign."82