O. B. U. These initials are commonly used in popular designation of ONE BIG UNION.

Occupational Diseases. In a broad and general sense, "the morbid results of occupational activity traceable to specific causes or labor conditions, and followed by more or less extended incapacity for work." The commoner forms of occupational disease may be classified according to cause and nature of injury as follows: (1) Diseases due to gradual absorption of poisons-e.g., lead poisoning. (2) Diseases in which the poison or germ enters the system through a break in the skin-e.g., anthrax. (3) Skin affections from acids or other irritants-e.g., eczema, dermatitis, etc. (4) Diseases due to fumes or dust entering the system through the respiratory organs -e.g., tuberculosis, gas poisoning, etc. (5) Diseases due to vibrations or constant use of particular members-e.g., neuritis, telegrapher's cramp, housemaid's knee, etc. (6) Miscellaneous diseases -e.g., caisson disease, miner's nystagmus, etc. In addition to all these, the term "occupational diseases" is often applied to many non-industrial ailments or disorders to which the public at large is subject, but which may nevertheless be caused or aggravated by specific conditions of labor. Nearly all civilized countries have enacted legislation designed to limit or prevent the more serious occupational diseases. In some cases the use of certain poisonous materials, as for example, white lead and yellow phosphorus, is prohibited altogether. In other cases children, women, or some classes of men are prohibited from handling certain dangerous materials or working under hazardous health conditions. The immediate reporting of all cases of occupational disease is required under the laws of seventeen states in this country. (See HEALTH HAZARDS; INDUSTRIAL MEDICINE; INDUSTRIAL HEALTH WORK; INDUSTRIAL PHYSIOLOGY; SAFETY FIRST MOVEMENT.)

Occupational Union. See CRAFT UNION.

Odborove Sdruzeni Ceskoslovenske (Federation of CzechoSlovak Trade Unions). The leading labor organization of CzechoSlovakia, formed as a separate entity in 1897, upon the refusal of the Austrian GEWERKSCHAFTSKOMMISSION to grant autonomy to the Czech unions under its jurisdiction. In 1913 the Federation had a membership of 104,574. Owing to war conditions this total had dropped to 23,932 in 1916. Since the proclamation of the Republic, however, the Federation has made tremendous headway. In 1920 the membership was stated to be 727,055, women members forming 28 per cent of this total.

Old Age Certificate. See EXEMPT CARDS.

Old Age Insurance. A form of SOCIAL INSURANCE Which provides periodic payments to workers who are wholly or partially incapacitated for wage-earning by reason of old age. Such payments are often termed "superannuation benefits." Compulsory old age insurance, in combination with invalidity insurance, has been established in eleven European countries, and in the United States for all Federal government employees in the classified civil service. Other countries have voluntary systems of old age insurance, carried on mainly by MUTUAL AID SOCIETIES, assisted or unassisted by the State. "Straight" old age pensions, that is to say, annual payments granted outright by the government on a non-contributory basis, are provided in several countries. ESTABLISHMENT FUNDS in the United States usually make provision for old age pensions, or "retirement allowances" as they are often called, and some of the larger national or international unions maintain special pension funds for this purpose. Superannuation benefits are paid by many of the large British trade unions. (See BENEFITS; MASSACHUSETTS SAVINGS BANK INSURANCE AND PENSION SYSTEM; SOCIAL INSURANCE IN RUSSIA; OLD AGE PENSION ACTS.)

Old Age Pension Acts. British Parliamentary enactments of 1908 and 1911, which provide for State pensions payable to every man and woman over the age of seventy whose income does not exceed £31, 10 shillings a year, and who has been for the last twenty years before receiving the pension a British subject and for twelve of those years (allowance being made for Crown service abroad and certain other instances) a resident in the United Kingdom. About one million persons in Great Britain now receive pensions under these Acts.

Old Age Pensions. See OLD AGE INSURANCE.

Old Unionism. In general, unionism of the conservative type, laying stress on insurance, craft autonomy, POLITICAL ACTION, etc., rather than on INDUSTRIAL ACTION; and largely or wholly ignoring the unskilled worker. (See NEW UNIONISM; BUSINESS UNIONISM; UPLIFT UNIONISM; COFFIN SOCIETY.)

Omnibus Injunction. See BLANKET INJUNCTION.

On-and-Off System. In general, the method of employing workers at irregular intervals and for uncertain periods, instead of for a definite number of hours each day or week. The "on-and-off system" is chiefly found in those industries which habitually utilize extra or relief workers, according to the varying pressure of work. Thus, in telegraphy, an extra or relief operator might be given two hours' work in the early morning, another hour at noon, and two or three additional hours in the early evening. As he would not know when he might be called on, he would have to be continuously on hand from early morning until late evening, although idle most of the time. (See GRASS WORK; BYE-TURNMAN.)

One Big Union. This term, like many others in the labor movement, is so loosely and variously used that any exact definition is difficult. To certain timid souls, any departure from strict CRAFT UNIONISM, any labor organization that follows the general structure and lines of an entire industry, is "One Big Union." On the other hand, the term is often applied to any radical labor body, however relatively limited in membership and influence-such as the INDUSTRIAL WORKERs of the WorLD, or the South Wales Miners' Federation, or the WORKERS' INDUSTRIAL UNION OF AUSTRALIA. Then there are certain labor organizations, notably the one formed among the workers of Western Canada in 1919, which have definitely adopted the title of "One Big Union." But, in the broadest sense, the term denotes an ideal or purpose, rather than any present actuality-an ideal and purpose that have long exerted a powerful influence on the working classes of every country. In the broadest sense, the goal in view is a single world-wide organization of labor, coherent and coordinate and all-embracing, recognizing no distinctions of nationality, color, sex, or occupation, and representative of the united economic force and social will of the working classes of the world. A necessary step toward the realization of the international "One Big Union" is the formation of a nationally inclusive organization in every country. In this national sense, the "One Big Union" movement has perhaps made the greatest progress in

Ireland, where the stress of the revolutionary republican struggle has united the working classes in a remarkably homogeneous body. (See CLASS UNIONISM; GRAND NATIONAL; IRISH LABOR PARTY AND TRADES UNION CONGRESS; IRISH TRANSPORT AND GENERAL WORKERS' UNION; AUSTRALIAN LABOR MOVEMENT.)

One-Break Day. A working day that is "broken" only by the interval allowed for the mid-day meal. The "one-break day" is a rarity in British industry, as usually several "breaks" or pauses are allowed for various purposes.

One Day's Rest in Seven. The insistence upon one day of rest for the worker each week has long been an important item in the programme of trade unionism. But it is recognized that the restday for all workers cannot be Sunday, because certain kinds of industries require continuous operation. Not the seven-day week but the seven-day worker is the objectionable feature. In nearly all European countries and in some half dozen states in this country, so called "rest-day laws" have been passed which recognize in some degree at least the principle of "one day's rest in seven." These laws generally name Sunday as the day of rest, but permit the operation of CONTINUOUS INDUSTRIES on that day provided the worker is given some other free day during the week. Another class of laws, originating primarily from religious motives, attempts to enforce Sunday as a day of rest; but such laws have for the most part proved ineffectual. Yet notwithstanding trade union pressure, legislative enactments, religious scruples, and the force of enlightened public opinion, large numbers of workers are still required to labor seven days a weeksometimes, as in the American steel industry, for twelve hours a day.

One-Man Shop. The form of small business-particularly common in the plumber, barber, tailor, job printer, blacksmith, painter, and carpenter trades-which is run by a single man or a partnership, with no other workers than possibly an APPRENTICE OF HELPER. The problem of the one-man shop is an important one to trade unions. The competition of such a shop, according to Dr. Weyforth, "is unregulated; its proprietor is left free to work at prices that are out of the question for an employer compelled to pay the regular union rate of wages, and to prolong his hours of labor to a time far beyond the limits fixed by the regulation of the union. In fact, the intensity of competition for business insures the working out of this result. . . . The result of the presence of these small shops is the undermining of the strength of the union, since the

large employer of labor is compelled to meet the competition of such shops, and, in doing so, feels himself handicapped by regulations in regard to wages and hours that do not apply to the small competitor." In some trades the one-man shop is sometimes referred to as a "bedroom shop."

One-Man Strike. A strike called to force the reinstatement of a single discharged employee. Such strikes are of fairly frequent occurrence, and sometimes involve thousands of workers-as in the case of the famous "Knox strike" of British railway workers in 1912. In such a strike it is of course a principle that the workers are contending for the principle that the employers' "right to discharge" shall not be arbitrarily or unjustly exercised. (See VICTIMIZATION.) One-Man Town. See COMPANY TOWN.

Open-Door Principle, This phrase has its origin in the statement frequently made by employers: "My office door is always open to any employee who wishes to lay a grievance before me.' Advocates of the "open-door principle" often assume that nothing further is needed to secure just and satisfactory industrial relations.

Open-Mouth Strike. A workers' term, applied to the plan sometimes adopted by dissatisfied waiters, retail clerks, etc., of telling customers the exact truth about adulterated or inferior articles which their employer offers for sale. Or, in connection with factory workers, it may consist in letting the public know about shoddy or dishonest methods followed in the manufacture of certain articles. This practice is, properly speaking, a mild form of SABOtage, the immediate purpose being to injure the employer. In France it is called la bouche ouverte "the open mouth."

Open Shop. Originally, an open shop was one where trade union members were permitted by the union to seek employment. To declare a shop "open" was equivalent to calling off a strike or boycott. Now, however, the term has a very different connotation. In present-day practice there are three main forms of open shop. First, there is the shop which, under JOINT AGREEMENT, is open alike to unionists and non-unionists, where both classes of workers are employed under the same wage scale and the same working conditions, without DISCRIMINATION on the part of either employer or trade union. Open shops of this type have long been common in certain national industries (as for example, the railways) where control on both sides is strongly centralized. They are in no way incompatible with the methods and aims of trade unionism, or with