Before the invention of the throttle valve, engine speed was controlled with the "hit or miss" system. Typically the exhaust valve would be held open as long as the engine speed was too high, only closing when the governor determined that engine speed had fallen too low.
When unloaded and at idle, such an engine fires perhaps once a second, or even less depending on its size. Really big ones might coast for five seconds before CHUFF! another "hit" takes place. I once saw a 20 HP twin-cylinder engine that was the size of a Ford Expedition (and probably weighed about as much) but I would wager it made enough torque to tow the Queen Mary down the Tri-State Tollway, and at idle it was firing about every ten seconds.
The methods used for carburation are also highly varied. These days we don't even think about it; we go find a venturi carb and use that--but before that was invented they had to find other ways. The one I really like--because it's AMAZINGLY SAFE!!!--is having a cone or tent of chicken wire. Gasoline is allowed to flow down from the top, covering the holes, and air is drawn through the mesh. Yeah, having a gigantic gasoline mantle with a puddle of gas at the bottom, there's absolutely nothing hazardous about that arrangement! It's a wonder we don't still use that method since there aren't any moving parts to worry about!
But once you get past a certain point in the development of small engines, they begin to resemble their modern equivalents. A one-cylinder engine from 1940 sounds and operates about the same as one from 1980.
I went to the Old Threshers' Reunion in Mount Pleasant, Iowa, in 2002, and there I saw a great deal of this kind of thing going on. What you seldom see (unless you spend the entire week/weekend at the event) is one of those old gasoline engines doing anything other than idling. It would be interesting to see one under load.
The other thing I found--that I had known about but never seen--were examples of the old Maytag gasoline-powered washing machines. This was a washing machine with a kick starter and it ran on gasoline; there were a ton of gasoline-powered applications for places without electricity.
Some guy took one of those old Maytag engines and with the addition of a lot of elbow grease and metal fabrication built himself an old-timey-style motorcycle, pretty much exactly the same way the first motorcycles were built.
* * *
Awakened at 7:30 by the application of modern gasoline engines: the neighbor's lawn service arrived and fired up mowers and leaf blowers, and after that I was awake.
Had trouble getting to sleep last night, anyway; I went to bed around 2 (after watching 3 more eps of Haganai Next) but couldn't drift off for quite a while. Alarm went off at 6:30; even so I fell asleep again and might have slept on if it hadn't been for the landscaping. *sigh*
Well, it could be worse, right?