This section is from the book "A Treatise On Beverages or The Complete Practical Bottler", by Charles Herman Sulz. Also available from Amazon: A Treatise On Beverages.
"After importation into this country, it is purified and prepared at 'whiting works' On its reception in the yards of the refining works, the crude chalk is stored in wooden bins, from whence, as needed, it is placed on wheel-barrows and shoveled from there into large cylindrical tanks, through which a stream of water is constantly rushing, where it is ground in water by massive rotating disks of iron, weighing from four to five tons each. From these tanks, by the current of running water, through an outlet on the side, flows the milky stream of suspended chalk, the impurities of silica and flint having to a large extent remained in the tank, from whence they are removed as occasion may require; the liquid is conducted through irregular, snake-shaped conduits, in order to separate the heavier, coarser particles of partly crushed chalk that may have been forced along by the current of liquid into a larger, longer and straight conduit, leading in succession to enormous wooden settling bins, having a capacity of over 5,000 gallons each of water. Now the running stream slowly flowing from the first to the last bin, through the long wooden channel provided for it, and connected with each bin in its passage, gradually deposits by gravity, on standing, the coarse grade in the first, finer in the second, still finer in the third, and so on until the last bin is reached, where the deposit is very slow and the product obtained correspondingly fine. At the base of each of these wooden bins are sluice gates opening into large, square, open iron tanks in front, under which is conducted, by draft, a current of strongly heated air from kilns, placed in front, so regulated in temperature as never to exceed 300° F. At the proper time, which ranges from five to six days for the first, to from six to eight months for the last, each bin is closed, the excess of water drawn off from above and pumped to a large tank upon the roof of the building, for re-use in grinding crude chalk, and the sluice gates below are opened to allow the white, viscid mass to flow into the flat, open tanks in front. As soon after heating as the mass becomes sufficiently plastic, it is cut into blocks of about 1 cubic foot, weighing 20, 30 or 40 pounds. The instrument used to do this division is technically called a ' scorer,' and is simply a long, stout pole, at the end of which is attached an L-shaped piece of iron. The mass is then again slowly heated from beneath, to still further expel moisture. From there these blocks are conveyed on tramways and taken to the drying-rooms above, where they are exposed on large trays to the continued draughts of atmospheric air, to promote thorough dryness; which point of the process is reached in one or more weeks, according to the condition of the weather. Then these blocks are powdered, bolted, graded and packed in barrels of about 300 pounds each, for shipment, as kiln-dried whiting.
"To a limited extent, in comparison with the previously described process, there is another mode of manufacturing practiced, whose only difference consists in the method of drying employed, which, in this instance, is done by simple exposure of the viscid, elutriated chalk to the air, without previously heating to expel contained moisture, and then proceeding as before mentioned. This product so obtained is called air-dried whiting, in contradistinction to the kiln-dried body, and must of necessity contain a certain percentage of unexpelled moisture; the presence of which rendering it, by giving what is called 'body,' more fit for certain uses in the arts than the kiln-dried substance.
"In the grades of whiting mainly supplied to markets, samples are presented in the order of their grade of fineness, viz.: 'chalk' in crude form; 'commercial,' the lowest grade made from chalk; 'gilded,' the next higher grade made from chalk; 'American Paris white,' the finest grade of all made from chalk; 'cliffstone,' from which only one grade is made, and that is 'cliffstone Paris white.' Each of these grades here shown are products of the kiln-dried method, and differ from each other in fineness of powder and certain physical qualities which adapt them for various special uses".