I was sitting on the other side of the glass drinking my morning tea when he hit with a loud 'thunk'.  I got up and went outside, taking my phone/camera with me to check on him, and take a couple of photos.  He lay there, upside down, never moving or blinking, but he was breathing rapidly, so I knew he was not dead - yet.  I took photos and went back inside to watch - leaving him to recuperate, or die, expecting the latter, but not wanting to stress him further by my presence.

The Western Scrub Jays, which had scattered, along with all the other birds, when the Merlin came in, now came back to check out this 'killer' bird who now looked dead himself - but they stayed in the nearby trees watching.  Not wanting to get too close.   The Merlin's breath slowed, and suddenly, with just a twitch, he popped up.  Now he was sitting on the flagstones, looking directly at me.  His feathers were somewhat disarrayed, but other than that he looked fine.  He closed his eyes and napped off-and-on for a few minutes, and then took off like a flash into a nearby juniper tree.

I haven't seen him since that morning, but I suspect I'll see him again checking out my feeders, and scattering the little birds.  Looking for breakfast.