Just drive outside the city limits into the countryside. Huge machines harvest fields of corn and soybeans. It is fall in Champaign County and it's a season of harvest.

Prior to the introduction of agricultural mechanization, the demand for farm labor was greatest at harvest time. In the mid 1900s, one machine was able to dramatically reduce the number of laborers needed to harvest grain and enable farmers to produce larger harvests. This machine was the combine.

The name "combine" developed when the harvesting and threshing operations of grain were "combined" into one complete machine, said Doug Bosworth, an adjunct professor in agricultural and biological engineering. Bosworth worked at John Deere and Co. for 35 years, 10 of which he spent in the manufacturing and test evaluation safety department with combines.

Horses and mules pulled early harvesting machines in the 1900s, said Carroll Goering, professor emeritus in the agricultural and biological engineering department. Wheat was cut in the fields, brought to the farmstead and ran through a thresher that separated the grain from the straw, Goering said.

While the modern combine is a machine used to harvest and thresh grains, such as wheat, the first combines were not used to harvest corn until sometime in the 1950s, Bosworth said.

Goering remembers shucking corn by hand in the days before the combine. Corn shucking, the process of removing the ears of corn from the stalks, was the main method of corn harvesting in the early 1900s, Goering said. Farmers wore cotton gloves with a curved hook strapped to the right hand to cut the corn. A wagon drawn by a horse would follow the farmer in the field. Ears of corn would fly through the air, hit a bank board that was attached to the opposite side of the wagon and fall into the wagon, he said.

"If you were really skilled and worked hard, a good man could (pick) 100 bushels of corn a day," Goering said.

Farmers would handpick corn as soon as it was dry around October and, if everything went well, they would finish harvesting by Thanksgiving, he said.

"If the weather was bad that year, harvesting might go all the way till Christmas," Goering said.

The first mechanical corn pickers were used as early as the 1930s.

"We really thought we had it made when we got a corn picker," said retired farmer Michael Hettinger from Pesotum, Ill. He recounted that his family used this machine long before the combine was available for corn harvesting.

Corn pickers had a one- or two-row corn header, a spout out the backside and a wagon pulled by the same tractor, Goering said. The 1930s to the 1950s marked the transition from handpicked to mechanically-picked corn.

Whether the corn was picked mechanically or by hand, a corn sheller was used to remove the corn kernels from the cob outside of the field, Goering said. Not every farmer owned a corn sheller because the typical farm size was a lot smaller than it is today. According to Goering, a farmer could justify ownership of a corn sheller if there were a dozen or so farmers in the area who would use this service.

Larry Sigler, a farmer from Villa Grove, Ill., recalled the late 1950s when his father owned a corn sheller. In the winter his father would take his corn sheller to other farms in the community and rent the device out to other farmers, Sigler said.

By the mid to late 1960s combines came into common use for harvesting corn. As the corn header became available on combines, the number of rows a farmer could harvest increased to two, four, six and now up to 16 rows of corn on today's combine.

"When the transition was made to corn heads, which mounted on front of combines, that was really revolutionary," Bosworth said. "It replaced the corn picker and created a greater capacity by shelling the corn for you."

Instead of having a grain platform with a sickle bar and a reel for wheat harvesting, a corn combine would have a header with units of gathering chains and snapping rows that removed the ears off the stalks and gathered them into the combine.

Bosworth stated that the farmer's safety was not part of the design process in early corn pickers and combines, where the operator sat just a few feet away from the dustiest part of the machine with all kinds of open chains, belts and gears moving around him.

"The environment for the operator is a thousand times better now than it is was 50 years ago," Bosworth said. "When I was growing up, every year someone in the community would end up with hands or arms getting (cut off by) corn pickers."

Since the earliest machines did not have cabs, the operator faced dangerous amounts of exposure to the sun, dust and noise levels, Bosworth said. Consequently, skin cancer, lung disease and hearing problems were common to those operators. However, the combines of the 21st century have cabs that are filtered, heated and air-conditioned, Bosworth said.

"The air is as good as you would have sitting in your living room," he said.

Combines today have hydraulic seat cushioning that allows the operator to set the seat for correct height and weight measurements, Bosworth said.

Most of the safety problems in combines today involve operator error. "People take off shields and stick their hands in places that they should not or they bypass normal safety operations," he said.

Bosworth sees a promising future for the combine machine. The trend for many years has been for more capacity, faster operating speeds and greater productivity, he said. While the combine is limited to the size of the machine that can be shipped on a truck or rail cart, the future of the combine will emphasize better engineering techniques that will put more value in the machines. According to Bosworth, the farmer adjusted the combine in the past by trial and error before he went into the field to harvest. With the sensors that are being developed in combines, the machines will be able to adjust automatically to a level where the process is most productive.

"At one time the speed of operation was what the operator could take, but with the operator environment in current machines, it is more about what the machine can take." Bosworth said. "(A combine today) can probably do in five minutes what a farmer could have done in a day previously."

In 2000, the National Academy of Engineering picked out the 20 greatest engineering achievements of the 20th century and ranked seventh on this list was agricultural mechanization.

"If you think about it, if it was not for agricultural mechanization, we could not have had space travel or computers," Goering said. "Everybody would have been out there on farms trying to grow food."

Goering said he believes that agricultural mechanization enormously increased farm efficiency and productivity, allowing people to branch away from agriculture and unleash their creative potential in other areas.