he was on duty with the Signal Corps for almost ten years and served as executive officer, until he was posted to field duty in 1876. Due to his old wounds rendering him unfit for strenuous work, he was retired at his own request in 1879. Bureau of American Ethnology During Mallery's tenure with the Signal Corps, he was briefly stationed at Fort Rice in Dakota Territory, where the indigenous system of communication by signs and gestures attracted his attention. He began to make note of them, which led to a parallel investigation of the pictographs on rocks, skins, and bark, of which he made a large number of transcriptions. He foresaw that these customs would ultimately be lost and forgotten as the Indians were brought more and more under the control of the authorities. Before Mallery began his researches it was generally supposed that the pictographs, some of which were believed to be of pre-Columbian origin, were simply pictures and devoid of meaning. He was gradually convinced that gesture-speech and the cognate pictographs formed a complete system, involving mythology and history and having an important relation to the spoken language. In 1877, as a result of this work, he was ordered to report to Major John Wesley Powell, who was doing a survey of the Rocky Mountain region. Later, when Mallery retired from the Army, Powell arranged for his appointment as an ethnologist with the Bureau of American Ethnology, which had been established that year. The first result was the publication, in 1880, of a pamphlet of 72 pages, with 33 figures, entitled "Introduction to the Study of Sign-language among the North American Indians as Illustrating the Gesture-speech of Mankind". This was intended as a manual for students so, and in the same year, there followed a quarto volume of 329 pages, "A Collection of Gesture Signs and Signals of the North American Indians, with Some Comparisons." The latter work was distributed to collaborators only. In 1881 Mallery's second important contribution was published in the First Annual Report of the Bureau, namely, "Sign-language among North American Indians Compared with that Among other People and Deaf-mutes." This treatise comprised 290 pages and was illustrated with 13 plates, a map, and 285 figures. While intended by its author as a preliminary report only, it is now considered to be the first authoritative exposition upon an almost entirely new subject in the