CELLULOSE. Cellulose is one of the most important of the organic substances of animals and plants. The group, or the amyloids comprise cellulose, starch, inulin, dextrine, . gum, cane sugar, fruit-sugar, and grape-sugar. This group, in some form, comprises the larger part, esti mated at seven-eighths of all the dry matter of vegetation, and as a rule they are distributed throughout all portions of plants. Samuel W. Johnson, M. A. gives an account of cellulose, its composition and amount in various plants, from which we make copious extracts • Every agricul tural plant is an aggregate of microscopic cells, i. e., is made up of minute sacks or closed tubes, adhering to each other. The outer coating, or wall, of the cell is cellulose. This substance is accordingly the skeleton or framework of the plant, and the material that gives toughness and solidity to its parts. Next to water it is the most abundant body in the vegetable world. All plants and all parts of all plants contain cellu lose, hut it is relatively most abundant in their stems and leaves. In seeds it forms a large por tion of the husk, shell, or other outer coating, but in the interior of the seed it exists in small quantity. The fibres of cotton, hemp, flax, white cloth and unsized paper made from these materials are nearly pure cellulose. Wood, or woody fibre, consists of long and slender cells of various forms and dimensions, which are deli cate when young (in the sap wood), but as they become older fill up interiorly by the deposition of repeated layers of cellulose, which is inter grown with a substance (or substances) called lignin. The hard shells of nuts and stone fruits contain a basis of cellulose, which is impreg nated with ligneous matter. When quite pure, cellulose is a white, often silky or spongy, and translucent body, its appearance varying some what according to the source whence it is ob tained. In the air-dry state, it usually contains about ten per cent. of hygroscopic water. It has, in common with animal membranes, the character of swelling up when immersed in water from im bibing this liquid; on drying again, it shrinks in bulk. It is tough and elastic. Cellulose differs remarkably from the other bodies of this group, in the fact of its slight solubility in dilute acids and alkalies. It is likewise insoluble in water, alcohol, ether, the oils, and in most ordinary sot vents. It is hence prepared in a state of purity,
by acting upon vegetable matters containing it with successive solvents, until all other mat ters are removed. Though cellulose is insoluble in, or but slightly affected, by dilute acids and alkalies, it is dissolved or altered by these agents, when they are concentrated or hot. The result of the action of strong acids and alkalies is quite various, according to their kind and the degree of strength in which they are employed. Pro longed contact with sulphuric acid con verts cellulose into dextrine, and finally into sugar. Other intermediate products are, how ever, formed, whose nature is little understood, but the properties of one of them is employed as a sort of test for cellulose. Boiling for some hours with dilute sulphuric acid also transforms cellulose into sugar and, under certain circum stances, cblorhydric acid and alkalies have the same effect upon it. The denser and more im pure forms of cellulose, as they occur in wood and straw, are slowly acted upon by chemical agents, and are not easily digestible by most animals; but the cellulose of young and succu lent stems, leaves, and fruits, is digestible to a large extent, especially in the stomachs of ani mals which naturally feed on herbage, and there fore cellulose ranks among the nutritive sub stances. Cellulose is a compound of the three elements, carbon, oxygen, and hydrogen. An alysis of it, as prepared from a multitude of sources, demonstrates that in 100 parts it con tains carbon. 44.44; hydrogen, 6.17; oxygen; 49.39, 100.00. The larger proportion of the cellulose stricture of the nutritious fruits, foli age, and grasses is easily converted into starch, and ultimately into sugar, by chemical means, and by animals when used as food, and known as carbohydrates. The mycelium of microscopic fungi consists, for the most part, of cellulose and, although the fungi are very low forms of plant-life; they are not only the principal forment of some of the organic acids, as the acetic, but they grow to maturity in them; while the woody cellulose of the higher plants , dissolves in the acetic ferments and becomes food for the cryptogams. Some varieties of mycelium take the blue stain by iodine and sulphuric acid, while _ other kinds are turned of an amber-color by the same tests. The amount of cellulose in plants is shown in the following table: Per cent.