The resulting rock, after being crushed, is passed through screens which separate it in three sizes, from one and one-half inch up going for export, between that and one-fourth inch for domestic, and the dust and one-fourth inch pieces being ground up and sold for direct use or to small factories. The Century Phosphate Co. has installed a system of dryers and do not wash the rock, but dry it thoroughly in mechanical dryers and then screen and separate it as above. The reason the larger pieces are as a rule of higher grade than the smaller, is that the dirt and impurity is mostly on the surface of the rock and the greater the proportion of surface to volume the lower the grade in B. P. L. and the higher in iron and alumina. Owners and operators of mines are gradually turning their attention to labor-saving devices for primary operations, and for systems of reclaiming the immense amount of waste that has heretofore gone on, both in the mining and the preparation of the rock. One marked step forward in the business is the establishment of a small mixing plant for making complete fertilizers, and the commencing of operations on a large acid phosphate factory, with prospects for additional ones later on. At least ten per cent of the present output is thrown away to prepare the high grade rock necessary, and this waste will make good 13 per cent acid phosphate, so that every year 50,000 tons of valuable material is absolutely thrown away. This is more phosphate rock than is annually used by any one fertilizer factory in the world, so far as known to the writer. This waste product could easily be transported to a local factory for an average cost of less than 50 cents per ton. Sulphuric acid can be bought laid down at Mt. Pleasant for $7 per ton. The mixing and other preparation will not exceed $2 per ton, so that using half acid and half rock the cost of the acid phosphate will not be more than $4.75 per ton, while it will probably sell for at least $8 per ton. From these figures we appear to be throwing into the waste pile at present material that should represent a profit of not less than $162,500 per annum. That this will be allowed to continue does not appear likely. The question might arise, however, “What will you do with the acid phosphate thus manufactured to keep from overcrowding or at least injuring the market?” I should answer this by calling attention to the immense area of land in Maury, Lawrence, Lewis and Hickman counties, known as “The Barrens,” which are gradually being denuded of their timber for cordwood that is shipped to Mt. Pleasant for use in drying the phosphate rock. There are at least 250,000 acres of this land, which is now readily purchasable at $3 per acre, with the cord wood on it. The wood alone will yield in value more than this price, thus leaving the land clear. Now, it has been demonstrated at Lawrenceburg, Summertown, Loretto, St. Joseph, Hohenwald