Blitz

Hi all, I was hoping to get some help identifying a McClellan saddle I just aquired. I can't figure out how to post photos, but it is stamped in two locations. The pommel is stamped under the rigging with what looks to be C.C.A, then under that, WMc. The cantle is stamped on the same side with: 19 ?D TR 1st Army I have no idea what any of that means, but I'd love to know more! Thank you, Jaclyn