[2][3] In 1855, he joined an exploring expedition under Lieutenant Williamson, sent out by the War Department to examine the country between San Francisco and the Columbia River.

He served as naturalist on an expedition in 1859 under Captain John N. Macomb, which explored southwestern Colorado and adjacent parts of Utah, Arizona, and New Mexico, finding the remains of the dinosaur Dystrophaeus.

[6] On 14 June 1861, he was elected a member of the United States Sanitary Commission due to his medical knowledge and experience in the army.

Dr. Newberry organized the whole of the comprehensive machinery of the commission in the large section that was committed to his care, and by his practical suggestions and enthusiasm stimulated the formation of the tributary societies.

During his connection with this institution, he created a museum of over 100,000 specimens, principally collected by himself, which served to illustrate his lectures in paleontology and economic geology.

At that time, it contained the best representations of the mineral resources of the United States to be found anywhere, as well as many unique and remarkable fossils.

Dr. Newberry's separate papers contributed to various periodicals included upward of 200 titles, chiefly in the fields of geology and paleontology, but also in zoology and botany.

Newberry named more than 50 species of Paleozoic age fossil vertebrates[1] and plants, some of which have been subsequently synonymized or renamed because of homonymy.