With all due respect, Zelia, I agree with Monterey. In 1907 the State of Mississippi began a biennial enumeration of Confederate soldiers and widows. For that year, in Leake County, J.N. Williamson stated that he enlisted in North Carolina. He lists his unit as Co. B(sic), 10th NC (in this enumeration there was no designation as to infantry, artillery, or cavalry.) As Monterey has pointed out, in Co. D, 10th NC Heavy Artillery, we find Newton, a musician, and James D, a private. Both of these men enlisted in Nash County, NC. On the 1860 census of Nash County, NC, in the household of Blufort and Mourning Williamson, we find James D, age 15, and John M(sic), age 12. On the 1870 census of Nash County, we find the household listed as Bluford and Mourning Williamson, and it includes Newton Williamson, age 24, a harness maker. Based on this information, I believe that the family tree (see link below) including these men is correct, and that James Dorsey, and John Newton Williamson were not the sons of John Milton and Selenah Tye Williamson, and that they did not travel to Mississippi to enlist, but came some time after the war.

http://trees.ancestry.com/tree/6069844/person/560860354