Sickle mowers, also called reciprocating sickle mowers, were originally invented for cutting cereal but was adapted to cut grass and plants in the 1960's. It became the standard tool used for cutting hay to feed various farm animals including sheep, goats, rabbits, cows, and pigs. They hay was stored to feed them during the winter months because grass was in short supply throughout that season.
To harvest hay there were many other reel mower to choose from including a rowse, rotary disks, and professional mowers but none could compare to the sickle mower. It was very easy to use for both large and small jobs. The sickle mower was attached to a bar featuring 5 blades that were each 7 inches long. While it wasn't the best option for larger commercial hay cutting it was a very efficient tool in the early days because it didn't break the strands or sprinkle them.
Electric Mower
For commercial hay harvesting the sickle mower [http://www.lawnmower-report.com/Brush_Mower/] just wasn't practical but with a few modifications the sickle haybine was created. This was done by combining the sickle mower concept with a strong frontal reel that could haul and bent stalks efficiently at a very fast rate. It also featured an internal device that could break stems of thick grass to allow the hay to dry very quickly. The early sickle mowers weren't capable of this.
Today the sickle mower is still in use by some homemakers and small farm owners. They are mostly considered to be antique machines though and collectors look for them all over. You can find some of them for a decent price on auction sites including Ebay.