horn in appearance. It is hard and more or less fragile, but difficult of pulverization, unless exposed to a freezing temperature, or thoroughly dried, and powdered in a heated mortar. Tragacanth has no smell, and very little taste. Its sp. gr. is 1.384. Introduced into water, it absorbs a certain proportion of that liquid, swells very much, and forms a soft adhesive paste, but does not dissolve. If agitated with an additional quantity of water, this paste forms a uniform mixture; but in the course of one or two days the greater part separates, and is deposited, leaving a portion dissolved in the supernatant fluid. The gelatinous mass is tinged blue by iodine T.S., and the fluid portion is not precipitated on the addition of alcohol. Tragacanth is wholly insoluble in alcohol. It appears to be composed of two different constituents, one soluble in water and resembling acacia, the other swelling in water, but not dissolving. The former differs from acacia in affording no precipitate with potassium silicate or ferric chloride. Official Preparation. Mucilago Tragacanthe.. Made by mixing 18 Gm. of glycerin with 75 C.c. of water, heating Mucilage of Tragacanth. to boiling, adding 6 Gm. of tragacanth, macerating, making the weight up to 100 Gm., and then straining forcibly through muslin (see page 314). ULMUS. U. S. Elm. [SLIPPERY ELM.] The inner bark of Ulmus fulva Michaux (nat. ord. Urticacea). This bark contains a mucilage which is capable of being precipitated by alcohol and lead acetate from its aqueous solution. It is much used as a demulcent. Official Preparation. Mucilago Ulmi. . . Made by digesting 6 Gm. of bruised elm in 100 C.c. of water (see Mucilage of Elm. page 315). SASSAFRAS MEDULLA. U.S. Sassafras Pith. The pith of Sassafras variifolium (Salisbury) O. Kuntze (nat. ord. Laurinea). This pith contains a delicate mucilage, which is not precipitated from its aqueous solution by alcohol. It is used for making the official mucilage, which is principally employed as an eye-wash. Official Preparation. Mucilago Sassafras Medullæ.. Made by macerating 2 Gm. of sassafras pith in 100 C.c. of Mucilage of Sassafras Pith. water and straining (see page 314). ALTHÆA. U. S. Althæa. [MARSHMALLOW.] The root of Althaea officinalis Linné (nat. ord. Malvaceœ). This root, which is generally imported from Europe, contains a large quantity of mucilage, C12H2O10 associated with asparagin, sugar, starch. It is used solely as a demulcent. and Official Preparation. Syrupus Althææ. . This syrup is made by pouring 400 C.c. of cold water, previously mixed Syrup of Althæa. with 30 C.c. of alcohol, on 50 Gm. of cut althæa, macerating for one hour, then straining through flannel without expressing; 700 Gm. of sugar are added to the liquid and dissolved by agitation without heat; 100 C.c. of glycerin are then added, and enough water to make 1000 C.c. (see page 302). LINUM. U. S. Linseed. [FLAXSEED.] The seed of Linum usitatissimum Linné (nat. ord. Lineæ). Linseed contains 15 per cent. of mucilage, C12H20O10, in the epithelium, and from 20 to 35 per cent. of fixed oil in the nucleus, besides resin, sugar, wax, etc. The mucilage is soluble in water, but more readily in hot water, forming a thick, viscid liquid. Alcohol and lead subacetate precipitate it from its aqueous solution. The mucilage is an important constituent; the seed is used in its unground state for making a demulcent infusion. Ground flaxseed is very useful to the pharmacist for making lutes, and, medicinally, it is used for making poultices. The fixed oil present is very valuable because of its drying properties. (See Oleum Lini.) Bael-fruit. Baobab. Benne Leaves. Blue-weed. Borage. Cashew-nut. Comfrey-root. Cydonium, Quince Seed. Evening Primrose. Hog Gum. Hound's Tongue. Jujube Berries. Laminaria. Lungwort. Mezquite Gum. Okra. Salep. Unofficial Mucilaginous Substances. The dried, half-ripe fruit of Egle Marmelos. Nat. Ord. Aurantiaceæ. From Adansonia digitata. Nat. Ord. Sterculiacea. Habitat, Tropical From Sesamum Indicum. Nat. Ord. Pedaliaceae. Habitat, India. Used From Echium vulgare. Habitat, Europe. Used chiefly as an emollient From Borago officinalis. Nat. Ord. Boraginaceae. Habitat, Southern From Anacardium occidentale. Nat. Ord. Terebinthaceæ. Habitat, Tropi- The root of Symphytum officinale. Nat. Ord. Boraginaceæ. Habitat, The seed of Cydonia vulgaris. Nat. Ord. Rosacea. Used for Mucilago From Enothera biennis. Nat. Ord. Onagraceæ. Habitat, North America. From Rhus metopium. Habitat, South America. Used as a demulcent. The fruit of Zizyphus vulgaris. Nat. Ord. Rhamnacea. Habitat, Asia From Laminaria Cloustoni. Nat. Ord. Algæ. Habitat, North Atlantic From Pulmonaria officinalis. Habitat, Europe. The fronds of Adiantum Capillus- Veneris. Nat. Ord. Filices. Used as a demulcent and stimulant. From Algarobia glandulosa. Habitat, Texas. The leaves and flowers of Verbascum Thapsus. Nat. Ord. Scrophulariacea. From Hibiscus esculentus. Habitat, Africa. From the tubers of Orchis mascula. Is very mucilaginous, only four grains being sufficient to make one fluidounce of water gelatinous. Virginia Lungwort. From Pulmonaria Virginica. Habitat, United States. Willow Herb. From Epilobium angustifolium. Nat. Ord. Onagraceae. Used as a tonic and demulcent. QUESTIONS ON CHAPTER L. AMYLACEOUS AND MUCILAGINOUS PRINCIPLES. What is starch? Give the Latin official name and description. What is its chemical composition? How is it made? What change takes place when starch is subjected to the action of diluted acids, diastase, or heat? Under what names is dextrin largely used in the arts? Describe its appearance. How may it be distinguished from gum arabic? In what solutions is starch soluble? What is the composition of inulin? Where is it found? In what particulars does it differ from starch? For what is starch used? Describe odor, taste, chemical reaction, and solubility. Give tests for identity. What are the official preparations of starch? Iceland moss-Give the Latin official name. Where is it found? What principles does it contain? What is its use? What official preparation of it is there? Where does this alga come from? Wherein does this principle differ from gum? What is arabin? What three proximate principles are found in gums? In what gums are these principles found? Wherein do gums differ from starch or cellulin? Wherein do gums differ from sugars? Gum arabic-What is the Latin official name? Describe odor, taste, and chemical reaction. What is its specific gravity? Of what does this gum mainly consist? Does neutral lead acetate precipitate its aqueous solution? Does basic lead acetate precipitate its aqueous solution? What action is produced by soluble silicates on ferric salts? What are the official preparations of acacia? Whence obtained? What are its constituents? What is its specific gravity? What color is produced when iodine T.S. is added to mucilage of tragacanth? Wherein does the portion soluble in water differ from acacia? What official preparation is there of tragacanth? Slippery elm-What is the Latin official name? Of what tree is this the bark? What does the bark contain? For what is it used? What official preparation is there of it? Sassafras pith-What is the Latin official name? Whence obtained? What does it contain, and for what is it used? What official preparation is there of it? Marshmallow-What is the Latin official name? What does it contain, and for what is it used? What official preparation is there of it? What part is official? Linseed-What is the Latin official name? Whence obtained? What does it contain? For what purposes is it used? Why is the fixed oil especially valuable? CHAPTER LI SUGARS AND SACCHARINE SUBSTANCES. SUGARS may be defined as organic bodies having a sweet taste, generally of vegetable origin and crystallizable, of a neutral reaction, soluble in water, their solutions being optically active to polarized light. The term sugar is popularly applied to but one product, saccharose, the sweet substance obtained from sugar-cane, beets, sorghum, etc. There are, however, many sugars varying not only in external appearance and properties, but also in chemical composition. They may be divided into two classes: 1. Fermentable sugars, and, 2. Non-fermentable sugars. 1. Fermentable Sugars.-This is by far the more important class, as it embraces the sugars which are largely consumed in food-products. It will be found convenient to divide this class into two subclasses: Glucoses, or sugars directly subject to vinous fermentation, and Saccharoses, sugars indirectly subject to vinous fermentation. The following table shows these in detail: Glucose (Dextro-glucose, or Dextrose). Grape-Sugar (Crystallized Lævulose (Lævo-glucose). Glucoses, C6H12O6. Rotates the plane of polarization strongly to the right. Obtained by treating starch with diluted sulphuric acid, neutralizing the acid with lime, separating the calcium sulphate, and evaporating the solution. Obtained by crystallizing the above-named solution. Rotates the plane of polarization strongly to the left. Found in the sugar-cane, and may be obtained from molasses, or by heating inulin under pressure with water. Maltose, C12H22O11 + H2O? Made by the action of diastase on starch. Fermentable only after being converted into a sugar belonging to the class of glucoses. 2. Non-fermentable Sugars.-These are sometimes termed saccharoids. Some of them have the chemical composition of glucose. Mannite, CH1406. Eucalyn, C6H12O6. Erythromannite, C12H30012. Isodulcite, C8H1406. Quercite, C6H1205. 69 Obtained from Manna and many other plants. Also called Melampyrite. Obtained from Melampyrum nemorosum. Obtained from muscular flesh. By decomposing quercitrin with diluted sulphuric acid. Obtained from Protococcus vulgaris, also called Phycite. From Pinus Lambertiana. Glucose, CH12O6, may be obtained from candied honey, from grapes, and from many other sources, but it is prepared from starch upon an immense scale by the action of very weak sulphuric acid. The term glucose is applied to the syrupy product of this process, while the name grape-sugar is applied to the solid product from the same source. The process is as follows. The corn is first soaked in warm water, and is then ground on specially-prepared stones with a stream of water. The meal is next passed into a trough, the bottom of which is made of fine bolting-cloth. Here the starch is washed through and led to large tanks, where it is allowed to settle. It is next beaten up with caustic soda to separate the gluten, and the starch is again allowed to settle in long shallow troughs. The starch, washed from all adhering alkali, is next beaten up with water into a cream, and conducted into the converting-tubs. Here the starch cream is treated with dilute sulphuric acid, and steam is allowed to bubble up through the mixture. This process of conversion, which is called " open conversion," is completed in about two hours. Another method is called "close conversion." The substances are enclosed in stout copper cylinders and subjected to the action of superheated steam. This process occupies about fifteen minutes. After conversion, the liquid is treated with marble-dust and animal charcoal. After neutralization, the liquid is filtered through cloth and animal charcoal, and is then conveyed to the vacuum-pan. When glucose syrup alone is desired, the process of conversion is stopped when the starch has disappeared, so that the syrup contains both glucose and dextrin, while, when solid grapesugar is desired, the conversion is carried further to the change of dextrin into dextrose. Glucose can be obtained as a hydrate in small and laminated crystals from aqueous solution, and anhydrous in hard crystalline masses either from alcoholic solution or from very concentrated aqueous solution. It is less sweet than cane-sugar. It is also less soluble in water, and much more soluble in alcohol. It has the sp. gr. 1.54-1.57 when anhydrous. Strong mineral acids hardly act on grape-sugar, but destroy cane-sugar with facility. On the other hand, grape-sugar is destroyed by alkalies, with which cane-sugar forms definite compounds. Dissolved in water and subjected to prolonged ebullition, grape-sugar undergoes very little alteration. solution rotates the plane of polarization of polarized light to the right, and is capable of undergoing the vinous fermentation directly, without passing through any intermediate state. It is characterized, also, in boiling solution, by reducing alkaline cupric tartrate (see Test-Solution of Alkaline Cupric Tartrate), producing a reddish precipitate. Manufactured glucose may sometimes contain calcium sulphate, which Its |