In a bulletin published by the U.S. Department of Agriculture in 1895, entitled, “Production and Price of Cotton for One Hundred Years,” the period commences with the introduction of Whitney’s saw gin, and ends with the year mentioned and with the production in that year of the largest crop the world had ever seen. No other agricultural crop commands such universal attention. Millions of people are employed in its production and manufacture. How insignificant compared with the wonder wrought by this one machine seems indeed any of the old seven wonders of the world! Although the displacement of labour occasioned by the introduction of the cotton-gin was not severely felt, as it was slave labour, yet that invention affords a good illustration of the fact that labour-saving machines increase the supply of the article, the increased supply lowers its price, the lower price increases the demand, the increased demand gives rise to more machines and develops other inventions and arts, all of which results in the employment of ten thousand people to every one thousand at work on the product originally. CHAPTER V. AGRICULTURAL INVENTIONS (_continued_). When the harvest is ended and the golden stores of grains and fruits are gathered, then the question arises what shall be next done to prepare them for food and for shipment to the distant consumer. If the cleaning of the grain and separating it from the chaff and dirt are not had in the threshing process, separate machines are employed for fanning and screening. It was only during the 18th century that fanning mills were introduced; and it is related by Sir Walter Scott in one of his novels that some of his countrymen considered it their religious duty to wait for a natural wind to separate the chaff from the wheat; that they were greatly shocked by an invention which would raise a whirlwind in calm weather, and that they looked upon the use of such a machine as rebellion against God. As to the grinding of the grain, the rudimentary means still exist, and are still used by rudimentary peoples, and to meet exceptional necessities; these are the primeval hollowed stone and mortar and pestle, and they too were “the mills of the Gods” in Egyptian, Hebrew and Early Greek days: the _quern_--that is, the upper running stone and the lower stationary grooved one--was a later Roman invention and can be found described only a century or two before the Christian era. Crude as these means were they were the chief ones used in milling until within a century and a quarter ago.