Here are a few more tidbits I picked up doing a ggogle search:
LYONS RURAL CEMETERY
Located in the village and town of Lyons, Wayne County, N.Y.
OFFINGER Martin, Co B N.Y. Mounted Rifles Vol., Sep. 9, 1831-May 21, 1918
1st NY Mounted Rifles
· Nickname -
· Recruitment area:
o Company B - NYC
· Dates of Service:
o Mustered in - summer, 1862
o Mustered out - Sept. 6, 1865, received designation, 4th Provisional Regiment, NY Vol. Cavalry
UNION VETERANS BURIED IN GREENWOOD CEMETERY--Dallas, Tx.
Sgt. Francis FEILING, - Co B, lst N.Y. Mounted Rifles
New York Civil War Soldiers Buried at the National Cemetery in Fortress Monroe, Virginia
Wells, J. R., Private, 1st NY Mounted Rifles, Co. B, died Mar. 18, 1862
Reading the first entry (I believe transcribed from your uncle's tombstone) it says Co. B NY Mounted Rifles. It doesn't say first or second mounted rifles. Are you sure it is the first? There is also a lot out there on the second as well as other companies of the first.
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