HYGIENE (Fr. hygiène, from Gr. ὑγιαίνειν, to be healthy), the science of preserving health, its practical aim being to render “growth more perfect, decay less rapid, life more vigorous, death more remote.” The subject is thus a very wide one, embracing all the agencies which affect the physical and mental well-being of man, and it requires acquaintance with such diverse sciences as physics, chemistry, geology, engineering, architecture, meteorology, epidemiology, bacteriology and statistics. On the personal or individual side it involves consideration of the character and quality of food and of water and other beverages; of clothing; of work, exercise and sleep; of personal cleanliness, of special habits, such as the use of tobacco, narcotics, &c.; and of control of sexual and other passions. In its more general and public aspects it must take cognizance of meteorological conditions, roughly included under the term climate; of the site or soil on which dwellings are placed; of the character, materials and arrangement of dwellings, whether regarded individually or in relation to other houses among which they stand; of their heating and ventilation; of the removal of excreta and other effete matters; of medical knowledge relating to the incidence and prevention of disease; and of the disposal of the dead.
These topics will be found treated in such articles as [Dietetics], [Food], [Food-Preservation], [Adulteration], [Water], [Heating], [Ventilation], [Sewerage], [Bacteriology], [Housing], [Cremation], &c. For legal enactments which concern the sanitary well-being of the community, see [Public Health].
HYGINUS, eighth pope. It was during his pontificate (c. 137-140) that the gnostic heresies began to manifest themselves at Rome.
HYGINUS (surnamed Gromaticus, from gruma, a surveyor’s measuring-rod), Latin writer on land-surveying, flourished in the reign of Trajan (A.D. 98-117). Fragments of a work on legal boundaries attributed to him will be found in C. F. Lachmann, Gromatici Veteres, i. (1848).
A treatise on Castrametation (De Munitionibus Castrorum), also attributed to him, is probably of later date, about the 3rd century A.D. (ed. W. Gemoll, 1879; A. von Domaszewski, 1887).
HYGINUS, GAIUS JULIUS, Latin author, a native of Spain (or Alexandria), was a pupil of the famous Cornelius Alexander Polyhistor and a freedman of Augustus, by whom he was made superintendent of the Palatine library (Suetonius, De Grammaticis, 20). He is said to have fallen into great poverty in his old age, and to have been supported by the historian Clodius Licinus. He was a voluminous author, and his works included topographical and biographical treatises, commentaries on Helvius Cinna and the poems of Virgil, and disquisitions on agriculture and bee-keeping. All these are lost.