The broadside publisher is correctly "De Marsan."

Oxford traces "chamber-lye" to the mid-sixteenth century and defines it as "Urine, esp. as used domestically or agriculturally, typically for a purpose such as washing, the preparation of crops, or the care of horses."

According to E. Merton Coulter's "The Confederate States of America, 1861-1865" (University of Texas, 1950):

"In 1862...the Niter and Mining Bureau was set up to intensify the production of niter as well as coal, copper, lead, iron, and other minerals. The Bureau now resorted to a method of production, familiar to Europeans, which involved the development of niter beds, or 'nitriaries' as they came to be called. Pits two feet deep were dug and filled with carcasses, stable manure, and decaying vegetable matter, and as decomposition progressed, putrid water and organic liquids collected from the towns and neighborhood were sprinkled over the beds. Eighteen months later, after occasional mixing operations, this soil was put in hoppers and water drained through it. The niter was recovered from this drainage. Stray dogs afforded many of the carcasses used, which led a wit to remark, ‘Soldiers using this powder are said to make a peculiar dogged resistance.'”

About Jon Haralson (1830-1912):

https://en.wikipedia.org/wiki/Jonathan_Haralson

The poems scan poorly to "John Anderson." "Maryland, My Maryland" is a more obvious melody, though the lyrics go better as a recitation.