Joshua was definitely in West Virginia in 1860. You can find him at Paint Creek, Kanawha County.
I thought ordance sergeant insignia had a star above the chevrons. That is what I thought the stars were for.
I know either Lorena got the Major's name wrong or that her handwriting was illegible. Dorothea did the best she could at transcribing, but she was quite elderly when she made the attempt. Lorena was only twelve when she wrote the letter. (I was thinking maybe Major was the first name and not the rank, but I could not find it.)
I know Lorena probably got some of her facts wrong. But she does place her father as a soldier in the area with the Confederates and thus far he shows up on no rosters at all. If you look through the cards for Joseph William Brown, you will see there are two ages given. One is 24 and one is 40 in 1865. My Joshua was 40 in 1865. As he never used his first name and ALWAYS went by JW, it is easy to see why people would think the JW was Joseph William. On ALL the documents that are actual documents and not just cards someone made out as they were trying to reconstruct records for the 8th, the ordnance sergeant is JW Brown, never Joseph William.
I did make jpgs of the cards in Joseph's file and could send them and you would see why I believe Joshua is the JW. For one thing, he is in the Cincinnati area in 1867 as a daughter was born in that area. I don't see a Joseph William there. His family was in Mercer County so if he survived the war, and descendants of his mother Lucy Abbot claim he did not: the family had several boys in the war and all but one died.
Thank you so much for searching for him. I do not think he will show up on any roster though as I truly believe he was overlooked because he NEVER used his full name, only JW. If I could go back in time, I would be tempted to slap him silly for doing that!