On #3 of this human interest slide show there is a guy mowing the lawn with an odd looking lawn mower. It doesn’t look like it even has any wheels. And what’s that metal hopper looking doohickey in the front? Is that used to catch clippings? How is it emptied?
It’s a cylinder mower - it has a rotating set of knives at the front that cut the grass and propel the clippings into the hopper - the machine moves on the fat rollers that you see underneath, plus a smaller set at the front which are adjustable so as to set the length of the cut.
This the traditional style of lawnmower that gives a classic striped effect to the lawn.
Thank you for the reply. 
Does the hopper come off or something? How is it emptied?
It is if I recall, rested on two lugs, and lifted straight off ( eg: not turned upside down at any point ) and emptied over a compost heap.
The first lawn mower was invented in 1830, in Stroud, by a cricket enthusiast. Damned nuisances they are too.
Mangetout and Claverhouse (which sounds like a quality brand of cylinder lawnmower) are exactly right. I was brought up on this kind of lawnmower and used to consider rotaries uncouth - although cylinders are less practical unless your lawn has been well levelled.
They’re not so bad when they’re motorised but as push mowers they used to be a pig to operate. That said, I’ve never even seen a push-operated rotary mower (as in, only muscle power turning the blade).
Hee, we just bought a push reel mover. Small amt of level grass to maintain. Not hard to push as long as the grass/weeds aren’t too high.
The striped effect is normally obtained by attaching a roller to the back of the mower like this one.
For sure, but cylinder mowers usually have a roller built in as an operating part of the mechanism, though there are such things as cylinder mowers without, or used to be. As I remember, Tom gets a going-over with one at the end of an episode of Tom and Jerry after trying to literally mow down a duckling, accidentally mowing its mother, and the bull duck showing up sporting anchor tattoos and Popeye muscles. 
Just so we’re all clear, it is a powered version of an old fashion push mower like this, correct? We had one of these when I was a kid. Even back then I thought they were kept around just for our parents to annoy us with a “Back in my day…” story. Never saw a powered version before. Can’t remember the last time I even saw a manual one*!*
Looks like a greens mower, used to maintain putting greens or very close cropped lawns.
I’ve seen those on golf courses. Reel or cylinder mowers are very good at getting a very level cut. Larger models are used on athletic fields. I knew a landscaper that used a somewhat larger unit than the one pictured in the OP. He said his maintenance costs would be lower for that type of mower, however he may have been comparing it to a tractor and not a rotary push mower.
The reel cuts cleaner due to a scissors cut, rather than a rotary which is more like a knife cut. It’s reely 
a necessity for grass maintained short.
Lower maintenance costs for the turf or the mower itself? Rotary blades are easy to sharpen and under commercial use, sharpened frequently. Reels don’t need to be sharpened nearly as often but are much more expensive to do. Things like stones are a very big problem for a reel blade, not so much for a rotary (other than the danger of a flying stone) as the blade is easier to grind the nick out, or much cheaper to replace.
That one has wheels, so it needs a roller as an accessory; the one in the OP’s picture runs on a split roller that is built in.
Could it be some version of a thatching machine to pull dead grass out of your lawn?
I couldn’t say, I haven’t seen him in years. I have a feeling he was talking about the difference between the wide reel and an equivalent rotary which I think would have required a double deck to cut that wide a swath, and I assume would have to be some kind of ride-on tractor which obviously would have had higher maintenance cost.
Here you go:
[quote=“bob_2, post:16, topic:726560”]
Here you go:
[/QUOTE]That’s the one, complete with cylinder mower with no roller*, and the blades driven directly by side-wheels.
*(Or at any rate one intended only to keep the mower on an even keel, and not to make lawn-stripes.)
But I worked at a golf course one summer (mid/late 70’s) and we didn’t use anything like that.
Here’s a mower that really doesn’t have any wheels.
[quote=“MikeF, post:19, topic:726560”]
Here’s a mower that really doesn’t have any wheels.
[/QUOTE]There was a mower like that back in the 60s. It must be nothing but trouble.