In my typical fashion when I have a project due, I'm currently immersed in researching something else, particularly the Mississippi Valley Sanitary Fair of 1865. I've unearthed all kinds of fascinating tidbits, but I've also accidently turned up some amazing hints about machine sewn quilts during the 1860s.
There's always been a bit of a debate about how charity quilts were assembled--hand quilted or tied. Almost all I've seen have been hand quilted. The quilts made to raffle off for soldier's aid were often very, very fancy.
Go to this page on the Ladies' Union Aid Society.
Scroll own to see the photo of the interior of the Boston branch of the US Sanitary Commission (the St. Louis fair was run by the Western Sanitary Commission, btw).
Two more photos down is a closeup of a quilt to be sent to the troops. Compared to the scale of the chair, the quilt blocks must have been quite large, say 8-10". In addition, it's pretty obvious that the quilting is done by machine.
That probably means something to only a handful of people, but let me just say--it's pretty cool information.