Also testifying was H. Ruby of Kansas.
Could this be the brother of George T. Ruby???

Interview April 22, 1880 and says:
b. New York (so was George)
Residence: Oswego, KS (southern)
Migrated from Central America to TX
Lived in Texas for 10 yrs
Lived in different places from Galveston to McLennan Co., TX - George lived in Galveston
Attended "Colored Man's Conference" in Houston (last July) as a delegate from his TX county
Then, migrated to KS
...

This could very well be 'Horatio Ruby', George's brother.