Of the other forms of balance, the Roman balance, or steel-yard, consists of a lever moving freely upon a suspended fulcrum, the shorter arm of the lever having a scale or pan attached to it, and the longer arm, along which slides a weight, being graduated to indicate quantities. It is commonly used for weighing loaded carts, for luggage at railway stations, &c. A variety of this, the Danish balance, has the weight fixed at the end of the lever, the fulcrum being movable along the graduated index. The spring-balance registers the weight of an article by the extent to which it draws out or compresses a spiral spring. It is of service where a high degree of exactness is not required, as in its domestic use, and it also finds application in the dynamometer for measuring horse-power of machinery. An extremely ingenious balance, used in the Mint and the Bank of England, for weighing 'blanks' and sovereigns, distributes them automatically into three compartments according as they are light, heavy, or the exact weight. The Roberval balance is a form in common use for weighing letters and parcels.—Bibliography: E. A. Brauer, The Construction of the Balance; E. Nicholson, Men and Measures: a history of weights and measures, ancient and modern.
Balance of Power, a political principle which first came to be recognized in modern Europe in the sixteenth century, though it appears to have been also acted on by the Greeks in ancient times, in preserving the relations between their different States. The object in maintaining the balance of power is to secure the general independence of nations as a whole, by preventing the aggressive attempts of individual States to extend their territory and sway at the expense of weaker countries. The first European monarch whose ambitious designs induced a combination of other States to counteract them was the Emperor Charles V, similar coalitions being formed in the end of the seventeenth century, when the ambition of Louis XIV excited the fears of Europe, and a century later against the exorbitant power and aggressive schemes of the first Napoleon. Since that time we have the instance of the Crimean War, entered into to check the ambition of Russia. Of late years there has been a marked tendency among British politicians to decry and impugn the principle of the balance of power, as calculated only to propagate a system of mutual hostility, and retard the cause of progress, by the expenditure both of money and life thus occasioned. An equilibrium between the various Powers is, of course, essential to the very existence of international law. The war of 1914-8 has proved to the world that in the absence of any central authority neither treaties nor signatures could prevent a State sufficiently powerful from ignoring
the law and acting solely according to its interests and ambitious designs. See Society of Nations.—Bibliography: Hume, Essay on the Balance of Power; Von Gentz, Fragments on the Balance of Power; Professor L. Oppenheim, International Law, vol. i; Vattel, Le droit des gens.
Balance of Trade, the difference between the stated money values of the exports and imports of a country. The balance is erroneously said to be 'in favour' of a country when the value of the exports is in excess of that of the imports, and 'against it' when the imports are in excess of the exports. The phrases date from the days of the mercantile system, the characteristic doctrine of which alleged the desirability of regulating commerce with a view to amassing treasure by exporting produce largely, importing little merchandise in return, and receiving the balance in bullion. In certain conceivable political and industrial conditions this may have had beneficial results; but its importance was greatly overestimated, and the state of this balance came to be regarded as an invariable criterion of the industrial condition of a country. The false analogy of the successful merchant who gains more than he spends became the basis of popular reasoning, the products of a country being mistakenly identified with its exports, its consumption with its importation. It is now generally recognized that if bullion be exported from a country it is because it is at the time the cheapest commodity available for export; and further, that there are certain natural limits to its undue exportation, in that the increased scarcity of money is attended with a fall in the money-value of other commodities, which thus in turn become preferable objects of exportation, while bullion flows back. The excess of the value of imports over that of exports, which is regarded by some as an adverse and alarming symptom in British trade, is in large part readily accounted for on the ground of shipping receipts, insurance returns, interest on capital employed in foreign trade, merchants' profits, and the income derived from foreign investments.
Bal´anus ('acorn-shells'), a genus of sessile cirripeds, family Balanidæ, of which colonies are to be found on rocks at low water, on timbers, crustaceans, shells of mollusca, &c. They differ from the barnacles in having a symmetrical shell, and being destitute of a flexible stalk. The shell consists of six plates, with an operculum of four valves. They pass through a larval state, in which they are not fixed, moving by means of swimming feet which disappear in the final state. All the Balanidæ are hermaphrodite. A South American species (Balănus psittăcus) is eaten on the coast of Chile, the Balănus tintinnabŭlum by the Chinese. The old Roman epicures esteemed the larger species.
Balapur´, town of India, in Akola district, Berar, with strong fort and fine pavilion of black stone. Pop. 10,500.
Bal´as, a name used to distinguish the rose-coloured species of ruby from the ruby proper.
Balasor´, a seaport town, Hindustan, presidency of Bengal, province of Orissa, head-quarters of a district and subdivision bearing the same name. It carries on a considerable traffic with Calcutta. Pop. 21,362.
Bala´ta, a gum yielded by Mimūsops Balata, a tree growing abundantly in British, French, and Dutch Guiana, Honduras and Brazil, obtained in a milky state by 'tapping' the tree, and hardening to a substance like leather. Used for similar purposes to india-rubber, and in the United States chewed as a masticatory.