poles or framework and so exposed that the sun and air have free access to all parts. This is the best and most approved practice. "Yellowing" of the leaf is very rapid after the plant is cut; it is the natural effect due to cutting off the food supply of the leaf and the consequent slow death of the vitality of the cells. It must be remembered that the leaves are large, varying in size (according to species) from 12 inches to over 2 feet in length. Such a leaf needs a large quantity of food and the sudden cutting off of the supply effects a rapid change in appearance. The leaves are allowed to hang on the scaffolds 3 to 5 days until they are fully yellowed. They are then ready for the process of "curing," which is the most important operation connected with cultivation. The "curing" and "fermentation" which the leaf undergoes are chemical actions and their success depends on the proper method of "yellowing." The leaves must not be exposed to the sun too long, because the cells would lose their vitality too rapidly and be unfitted for the new part they have to play in the curing process. The chemical changes will be explained in subsequent chapters. It is desired that the reader should understand that to ensure a successful final issue the planter has need to watch continuously and to know all the conditions. If the leaf does not "yellow" properly no amount of after care in curing will make up for this deficiency. In tobacco growing as in everything else, to ensure final high quality each step in the process must be executed with skill, care, and judgment. The yield of tobacco per acre varies from about 300 lbs. of leaf in the southern states to 1,000 lbs. or more in the eastern. 700 to 800 lbs. per acre is considered a good average crop. REFERENCES KILLEBREW AND MYRICK. _Tobacco leaf; its culture and cure, marketing and manufacturing._ Part I. New York, 1897. BILLINGS, E. R. _Tobacco; its history, varieties, culture, etc._ Chapter XIII. Hartford, Conn., 1875. LAURENT, L. _Le tabac; sa culture et sa préparation production et consummation dans les divers pays._ Paris, 1900. U. S. DEPT. OF AGRICULTURE. Farmers' Bulletins Nos. 6 and 60. _Tobacco._ U. S. DEPT. OF AGRICULTURE. Bureau of Plant Industry. Bulletin 96. _Tobacco breeding._ CHAPTER III THE WORLD'S PRODUCTION OF TOBACCO TOTAL PRODUCTION. COUNTRIES WHICH CULTIVATE TOBACCO. PRODUCTION IN THE NEW WORLD OTHER THAN IN THE UNITED STATES. THE WORLD'S PRODUCTION OF TOBACCO The world's recorded annual crop of tobacco leaf is over one million tons. The latest government figures available are those for 1912 and 1913, and show 2,696,401,379 and 2,722,190,030 lbs. respectively. Of this amount Asia and America produce each about 350,000 tons, Europe about 250,000 tons and the rest of the world the balance. The details of the production in the U. S. will be given in the next chapter.