In 1839 the cadets at the Military Academy discarded the bell-crowned caps they had worn since 1821 and wore a cylindrical black shako similar to that worn by the Regular artillery and infantry. The artillery gilt eagle and crossed cannon replaced the diamond-shaped plate on the front. In 1842-1843 the crossed cannon were replaced by the engineer castle as more in keeping with the original mission of the Academy and the general orientation of its curriculum.

Shortly after the beginning of hostilities with Mexico in 1846, the Congress authorized the enlistment of a company of "engineer soldiers" that was designated the Company of Sappers, Miners, and Pontoniers. These were the first enlisted men authorized the Corps of Engineers since the period of the War of 1812. The headgear for these men was prescribed as "Schako—same pattern as that of the artillery, bearing a yellow eagle over a castle like that worn by the Cadets."[76]

Struck in thin to medium brass, this plate is the familiar turreted castle of the Corps of Engineers so well known today. It was worn below the eagle.

¶ To complete the branches of the Regular Establishment during the Mexican War period, the Regiment of Voltigeurs and Foot Riflemen must be mentioned, although they were apparently without any distinctive branch insignia.

The regiment was constituted on February 11, 1847, and its uniform[77] was prescribed 9 days later in the War Department's General Order No. 7. However, the regiment was issued infantry woolen jackets and trousers and never received what little gray issue clothing was sent to them in Mexico almost a year later. Uniform trimmings were to be as for the infantry, with the substitution of the letter "v" where appropriate. So far as presently known, this substitution affected only the button pattern—an appropriate letter "v" on the shield centered on the eagle's breast.

The 1851 uniform regulations radically changed almost every item of the Army's dress. Most of the distinctive devices were also altered, although more in size and composition than general design. Some devices were completely eliminated. While officers retained insignia of their arm or branch on their hats, enlisted personnel, with the exception of those of engineers and ordnance, had only the letter of their company, their particular arm being designated by the color of collars, cuffs, bands on hats, pompons, epaulets, chevrons, and the like. A newly designed sword or waist-belt plate was prescribed for all personnel. All items of uniform and insignia authorized in 1851 were included in an illustrated edition of the Regulations for the Uniform and Dress of the Army of the United States, June 1851, published by William H. Horstmann and Sons, well-known uniform and insignia dealers in Philadelphia.[78]

POMPON EAGLE, 1851

USNM 604853 (S-K 998). Figure 43.