A study of the geographical distribution of the coffee tree shows that it is grown in well-defined tropical limits. The coffee belt of the world lies between the tropic of cancer and the tropic of capricorn. The principal coffee consuming countries are nearly all to be found in the north temperate zone, between the tropic of cancer and the arctic circle. The leading commercial coffees of the world are listed in the accompanying commercial coffee chart, which shows at a glance their general trade character. The cultural methods of the producing countries are discussed in chapter XX; statistics in chapter XXII; and the trade characteristics, in detail, in chapter XXIV, which considers also countries and coffees not so important in a commercial sense. Mexico is the principal producing country in the northern part of the western continent, and Brazil in the southern part. In Africa, the eastern coast furnishes the greater part of the supply; while in Asia, the Netherlands Indies, British India, and Arabia lead. Within the last two decades there has been an expansion of the production areas in South America, Africa, and in southeastern Asia; and a contraction in British India and the Netherlands Indies. _The Shifting Coffee Currents of the World_ Seldom does the coffee drinker realize how the ends of the earth are drawn upon to bring the perfected beverage to his lips. The trail that ends in his breakfast cup, if followed back, would be found to go a devious and winding way, soon splitting up into half-a-dozen or more straggling branches that would lead to as many widely scattered regions. If he could mount to a point where he could enjoy a bird's-eye view of these and a hundred kindred trails, he would find an intricate criss-cross of streamlets and rivers of coffee forming a tangled pattern over the tropics and reaching out north and south to all civilized countries. This would be a picture of the coffee trade of the world. It would be a motion picture, with the rivulets swelling larger at certain seasons, but seldom drying up entirely at any time. In the main the streamlets and rivers keep pretty much the same direction and volume one year after another, but then there is also a quiet shifting of these currents. Some grow larger, and others diminish gradually until they fade out entirely. In one of the regions from which they take their source a tree disease may cause a decline; in another, a hurricane may lay the industry low at one quick stroke; and in still another, a rival crop may drain away the life-blood of capital. But for the most part, when times are normal, the shift is gradual; for international trade is conservative, and likes to run where it finds a well-worn channel.