HYGIENE, hifji-i'in (from Fr. hygiene, from ifyiaivetv, hygiainein, to he healthy, from hygies, healthy). The branch of cal science which deals with the preservation of health. Within its scope are all measures taken for the acquisition and preservation of health, except those involving purely medical and surgical means. Hygienic measures were a part of religious observance among the •eWS, as well as among the people of Assyria and India. and their enforcement lay with the priests. Among the Greeks these duties were transferred to the physicians. Hippocrates's work on Air, Water, and Places was largely responsible for this change. (See In the second book of Homer's Odyssey there is all count of the sanitary precautions taken by ses after the killing of the wooers. The place of slaughter was cleansed and disinfected by ing and washing, and by burning sulphur. Little attention appears to have been paid to the fected individual in the olden time. when the panic ensuing upon a plague caused expulsion or expatriation of the sufferers. Laws were framed to protect the public from lepers, for example, by expelling them and burning their houses. In 142:3 Venice established its first lazaretto, and in 1485 a permanent health magistracy was cre ated in that city. In 1532 an act of Parliament authorized in England the issue of commissions of sewers for overlooking of sea banks and sea walls, and the cleansing of rivers, public streams, and ditches." In 1552 Shakespeare's father was fined for throwing filth into the street. and again in 1558 for not keeping his gutter clean.
Roman law provided no protection for the in dividual. Greek and Latin writers treated of diet and exercise for the patrons of literature, for princes, and for the wealthy. From the school of Salernmn, about the twelfth century, issued the Code of Health, which was printed in 1480, and for two centuries thereafter remained the standard work on personal hygiene. Despite the stringent laws seeking to prevent plague which were enacted by James I.. and the establish
ment of lazarettos into which ships discharged their cargoes for detention and airing, serious outbreaks of the dread disease occurred in 1625 and 1629-31. In 1665, according to Macaulay's estimate, the number of deaths from plague dur ing one period of six months reached more than 100.000.
At the close of the eighteenth century little ad vance had been made in hygienic knowledge be yond the discovery by Woodhall, in 1617, that scurvy was prevented by the use of lemon-juice; the discovery by Morton, in 1697. that foul air produced disease in some way; and the introduc tion from China into England in 1717 of inocula tion with smallpox virus by Lady Mary Wortley Montagu. Differentiation of fevers began early in the nineteenth century. Following the cholera epidemic in London of 1831-32. newly awakened interest resulted in the formation in 1838 of a system of registration of deaths in that city. The establishment of the fact of water-borne diseases was made by the investigations of Dr. John Snow into the cholera outbreak in London, in 1848-49. From this date investigation has been systematically pursued into the causes of death; the causes of disease, its spread, and the agencies that produce it; and into the conditions that promote health. The use of the microscope, the study of bacteriology, of pathology, of the chemistry of food, of climate, and of exercise have all added to the knowledge that has in creased the useful application of hygienic prin ciples in our day. Sanitary laws have been enacted which control unhealthful agencies and aim to safeguard and regulate commercial as well as domestic relations.
Hygiene may be variously classified. according to its relatiors, and the objects in view. There is the hygiene of the individual, of the family, and of the municipality or State; which may be denominated personal, domestic, and public hy giene.