Wednesday, September 3, 2008
No Different than the Ancients
I think we have all seen the images of third world people harvesting wheat. Bundles, or even just loose stocks of grain are brought in from the field, usually by hand. The cut plants are spread out on the ground where some local form of domesticated four legged animal is tethered to a crude home build swivel and walks on top of the grain in an endless circle. As the animal passes by, a person with a wood rake pulls away the straw. Next, women with large shallow baskets scoop up what remains and toss it into the air, catching the heavier grain and allowing the lighter chaff to blow away. It is an ongoing process, more grain stocks are thrown under the hooves of the animal, more straw is raked away, more of the separated heads are tossed in the air and caught.
This is one of the earliest documented agricultural process, the harvesting of wheat.
What is absolutely amazing is that the modern day giants of farm equipment, the combine is nothing more than a mechanical version of that same process. The mechanics have improved, yes, but the theory, the actual how it gets done has not changed in thousands of years.
A combine got its name simply because that is just what is does, it "combines" all of those ancient process I just described into one mobile machine.
On the front, the header, with its tell tale turning reel cuts the grain stock and feeds it into the machine, just like the native men hauling bundles from their field. The stocks, straw and grain head are then fed into a rotor surrounded by a concave. The spinning rotor rubs the material against the bars of the concave causing the grain heads to separate from the straw and the actual kernels to pop out from the protective chaff. High capacity, but it is no different than a mule or ox walking across the grain endless times.
Falling from the rotor and concave, the longer straw is shook loose as it and the kernels "walk across" the first of two screens. Like a man raking away the long stocks. All the while, a powerful fan is blowing air across these screens, causing the lighter straw and chaff to exit out the back of the machine and the heavier grain to fall through the oscillating screens. This is exact same theory as women with woven baskets "winnowing" the wheat in the hot afternoon breeze. Finally, the cleaned grain is elevated to a holding tank at the top of the machine where it is periodically augured into trucks. Just as the women empty their baskets of the precious grain.
We think we are so smart and advanced. In a combine, there are no new ideas.
I've been doing some custom wheat cutting over the past two weeks. The whole time I kept thinking, what I'm doing is etched in stone in Egypt and in caves here in the US. I'm no different than the ancients.
The proof is in the pudding. A landowner inspects a load of wheat I just combined to make sure the ancient principles are being closely followed.