Switzerland and Spain in the order named. Over 392,000,000 pounds was imported into this country in 1919. Of the 551,000,ooo pounds of these products produced in 1911, the largest amount came from San Thome and Principe,1 Ecuador, Brazil, Trinidad, Gold Coast, Dominican Republic and Venezuela. The amount annually consumed in the entire world is increasing very rapidly. MATE, KHAT, KOLA, GUARANA, COCA Mate or Paraguay tea, a beverage made from the leaves of a species of holly (Ilex Paraguayensis) growing abundantly in Paraguay, Brazil and other South American countries, is very commonly used by the natives. The leaves are dried and slightly roasted and afford a somewhat bitter, aromatic and astringent beverage. They contain caffein, a yellowish essential oil, and only about one-tenth as much tannin as tea. The natives prepare the tea by pouring hot water on the leaves, contained in a gourd, and drink it through a tube called a "bombilla," which is often made of silver, and has a perforated bulb at the end. Maté is the universal drink of more than 15,000,000 people in South America, and the annual crop exported from Paraguay is more than four thousand tons. 2 Khat, a tea that has been used in Arabia from the earliest times, consists of the leaves of the shrub Catha edulis, which grows wild in Abyssinia and is cultivated in Arabia. The leaves of the plant are dried and used for making a decoction which contains an active principle called katin, having stimulating properties similar to caffein.3 The kola nut is the fruit of the Sterculia acuminata, a tall tree growing in Jamaica, on the west cost of Africa, in East India, Ceylon and Brazil. The active principle, called kolanin, is developed by fermentation in the process of curing and under the 1 Dept. Commerce and Labor, Spec. Consular Rep. No. 50. 2 Loc. cit., Tibbles. 3 Nat. Geog. Mag., April, 1917. influence of an enzyme, is broken down into kola-red, caffein and tannin. The beverage is made by boiling the powdered nut with water for five minutes. Kola has the property of increasing the number and energy of muscular contractions, preventing fatigue and rendering the respirations more free. It is mildly stimulating to the heart and nervous system. Opinions are divided as to whether its secondary effects are as injurious as many other narcotics. As a substitute for food on long or forced marches, kola is said to sustain the strength for a longer time and serve better than tea or coffee.1 Guarana is a preparation made in Brazil and other South American countries from the crushed seeds of the Paullinia Cupana. It contains from 3.5 per cent. to 5 per cent. of alkaloidal substances mostly caffein, besides tannin, sugar and a volatile oil. The product comes into the market in long sausage-like rolls, from which pieces are broken and infused in cold water to make a refreshing beverage. Guarana acts as a stimulating beverage and enables the traveler to resist hunger and fatigue during long marches. Coca is made from the leaves of the enythroxylen coca which grows in Bolivia, Peru and other parts of South America. The natives chew the leaves. The annual consumption is said to be 100,000,000 pounds. The stimulating effect of coca is due to the presence of cocaine (C17H21NO), ecgonin, and some aromatic substances. It produces some excitation, and causes the sensation of hunger to disappear. It also allows fatigue to be borne for a time without recourse to food. It is less exciting than either tea or coffee, but has a more pronounced action on the heart. The effect of the continued use of cocaine on the system is extremely bad, and the cocaine habit like the morphine habit is very difficult to overcome. (See p. 496.) The sale of coca products in the United States, is only allowed under very stringent regulations. 1 Practical Dietetics, Thompson, p. 225. Diet and Dietetics, Gautier, p. 277. CHAPTER XX WATER AND EFFERVESCING BEVERAGES ("Soft Drinks") Water as an indispensable constituent of foods has already been discussed. The amount of water in foods is always surprising. Upon analysis the vegetables and fruits are found to contain from 70 to 90 per cent. of water. Asparagus, celery, lettuce, pumpkins, cucumbers and melons are all high in water and correspondingly low in food material. The cereals, and legumes, and such tubers as potatoes contain large quantities of water, but not so much as fruits. Fish, meat and game contain from 60 to 80 per cent. of water. As there is a tendency to use an insufficient amount of water or other liquids with the daily diet, this quantity of water in the foods assists greatly in keeping up the fluidity of the food mass as it passes through the body. Recent investigations seem to indicate that water and other liquids taken in quite large quantities with the food tend to assist digestion rather than retard it, as was formerly taught. Although this large amount of water in the food, as furnished by the plants and animals for sustenance of man, is of value in the processes of digestion, at the same time it renders the food much more liable to spoil, and so very early there arose the practice of drying foods in order to keep them. WATER AS A BEVERAGE Water is the basis of all beverages for an examination shows that most of them are simply water flavored with alcohol, vegetable extracts, sugar, acids and fruit ethers, holding in solution alkaloids or proximate vegetable substances, and often surcharged with carbon dioxid gas. Potable waters, or those that are suitable to use as a source of domestic supply and for drinking, may be derived from public or private sources. The advantage of a public supply is that the whole quantity used by the city may be supervised frequently and carefully analyzed, thus insuring its purity as a supply. If the water is drawn from numerous wells, springs and cisterns, it is liable in each individual case to be contaminated. On isolated farms or in small villages there are always sources of filth near at hand in stables, closets, drains, cess-pools or hog wallows. Few persons appreciate how readily surface water may find its way from such sources of filth into the domestic water supply. It may percolate through the soil without any sensible purification, or it may run over the surface and fall into the well or cistern, carrying with it any germs of disease that may have been in the filth with which it came in contact. Because a water is clear, colorless and tasteless it is often considered safe, while the fact remains that some of the most dangerous waters do not betray their character by their taste, color or appearance. SOURCES OF SUPPLY Domestic supplies may be obtained from a spring, brook, river, pond or lake, or from a shallow (dug) well, a driven well or an artesian well. The rain water may also be collected from the roof, and stored in a cistern or reservoir. Impurities in Water The substances contained in water are of two general classes, mineral and organic. As water percolates through the soil and over the rocks it dissolves various mineral substances. This solution in water is aided by the carbon dioxide and other gases that are dissolved in the water, and the rocks are disintegrated by changes of tempera ture and frost. The mineral substances ordinarily found in water include the ions, calcium, magnesium, sodium, potassium, iron, aluminum and a few other metals associated with such acid ions as chlorine, sulfur, and the sulfate, carbonate, nitrate, phosphate, and silicate ions. Hard and Soft Water When there is considerable calcium or magnesium salts in the water it is known as a hard water. If this is in the form of carbonate the water is said to be "temporarily hard," while if in the form of sulfates the water is "permanently hard.” Chlorides and sulfates of sodium, iron, etc., are also found in permanently hard waters. Much of the calcium and magnesium present in a temporarily hard water is precipitated by boiling, as it is held in solution by the excess of carbon dioxide which is removed by boiling. This accounts for most of the incrustation on the bottom of a tea-kettle or other vessel in which hard water is boiled. If the mineral substances are not too abundant they are not considered particularly injurious. For some culinary purposes, hard water is not satisfactory. For making tea, however, a moderately hard water is preferred. For laundry purposes hard water is very unsatisfactory, as the soap which is added is first used up in precipitating a lime or magnesia soap, before a permanent lather will form. When large amounts of water are prescribed for drinking, the water should be as soft as postible. The diuretic action of large quantities of water is well established. If an abundance of water is taken into the system the temperature of the body falls and the number of pulsations of the heart and of the inspirations is diminished. Table Waters Many of the so-called "table waters" are comparatively free from mineral matter. In the Appalachian and Green Mountain regions of the United States where the rocks are of granite, trap or sandstone, and where there is very little soil through which the |