Pappy sailed on the USS Niagara in 1920

Looking at US Census data for 1920, I believe my great-uncle "Pappy" Markell (the nickname used by some of my cousins) served on the USS Niagara, anchored in Mexico during the Census period of Feb. 1920. The Niagara was a yacht purchased by the Navy from Howard Gould of NYC. 

Following WWI, the Niagara stayed in the Gulf of Mexico and Caribbean waters during early 1920s . . . when Pappy was on board. More about the USS Niagara here. Pappy was on back on shore for good, it seems, by 1921 when he married his wife, known in the family as Sweetie. (updated 2022 with image and new link).