cropped from Bicyclists on Minerva Terrace; photo by F. Jay Haynes - used by permission of Montana Historical Society-unauthorized use prohibited
Musician William W. Brown, Co. B (148 lbs.)
The following from On the Trail of the Buffalo Soldier II (Frank Schubert):
Brown, William W .; 25th Inf. Musician, B/25th Infantry, rode in 25th Infantry Bicycle Corps, Ft. Missoula, MT. Summer 1896. SOURCE: Sorenson, List of Soldiers...
Alice A. Brown, age 49, 1126 E. 53rd Street, Los Angeles, widow of William W. Brown, veteran of Spanish-American War, who served in A Company and Band/24th Infantry and 25th Infantry, is pensioned, File C 1243461; married to first husband, William H. Oliver, Band/9th Cavalry...
SOURCE: VA File C 1392575. George W. Proleau
In the Minerva Terrace picture, William Brown's trouser legs clearly have two solid strips, the insignia of a musician http://www.ushist.com/uniforms_indian-wars_us.htm
I've searched register of enlistments and am striking out. There are a lot of William Browns.