It must not be forgotten that the coal consumption of a plant depends upon the economy of heating means in the distilling apparatus, the perfection with which the heat of the vapors is used to heat the wash, the perfection of the boiler grates and the method of firing. These latter matters should be obvious to any distiller, but it is in economy in little things that the successful operation of a plant resides. Nothing is more surprising than the difference in the coal consumption of different distilleries. Some use a third more than others. This is caused by poor coal, by poor firing, by poor boilers, by hard water, or by poor distilling equipment. With regard to the latter this word of advice may be given: The greater the number of plates in the distilling column, the less the coal consumed per gallon of alcohol produced. It must, however, be taken into account that a large number of plates in a column means a column of considerable height and that in turn means a correspondingly tall still house and increased first cost. Hence it is more economical to use the best forms of traps on the plates and fewer plates, and the best forms of these traps as pointed out in Chapter III, are those wherein the largest quantity of vapor in a finely divided state may come into contact with the greatest number of liquid particles. In conclusion it may be said that dirt, neglect, carelessness and a too great desire for economy in first cost are all factors in lowering the economical productiveness as well in a distillery as in other manufacturing plants. CHAPTER XIII. DE-NATURED ALCOHOL AND DE-NATURING FORMUL∆ The uses of alcohol are very numerous and varied, the principal being, of course, for the production of all alcoholic liquors such as brandy, gin, rum, whiskey, liquors, etc.; that distilled from grain is almost entirely consumed in the manufacture of whiskey, gin, and British brandy. In the arts, strong alcohol is employed by the perfumers and makers of essences for dissolving essential oils, soaps, etc., and for extracting the odor of flowers and plants; by the varnish-makers for dissolving resins; by photographers in the preparation of collodion; by the pharmaceutists in the preparation of tinctures and other valuable medicaments; by chemists in many analytical operations, and in the manufacture of numerous preparations; by instrument makers in the manufacture of delicate thermometers; by the anatomist and naturalist as an antiseptic; and in medicine, both in a concentrated form (rectified spirit), and diluted (proof spirit, brandy, etc.), as a stimulant, tonic, or irritant, and for various applications as a remedy. It is largely consumed in the manufacture of vinegar; and in the form of methylated spirit it is used in lamps for producing heat. It has, in fact, been employed for a multitude of purposes which it is almost impossible to enumerate.