HYSSOP (Hyssopus officinalis), a garden herb belonging to the family Labiatae, formerly cultivated for use in domestic medi cine. It is a small perennial plant about 2 ft. high, with slender, quadrangular, woody stems ; narrowly elliptical, pointed, entire, dotted leaves, about I in. long and 1- in. wide, growing in pairs on the stem ; and long terminal, erect, half-whorled, leafy spikes of small violet-blue flowers, which are in blossom from June to September. Varieties of the plant occur in gardens with red and white flowers, also one having variegated leaves. The leaves have a warm, aromatic, bitter taste, and are believed to owe their properties to a volatile oil which is present in the proportion of a to 2%. Hyssop is a native of the south of Europe, its range extending eastward to central Asia, and has become naturalized in North America from Maine to Ontario and southward and also on the Pacific coast. A strong tea made of the leaves, and sweetened with honey, was formerly used in pulmonary and catarrhal affec tions, and externally as an application to bruises and indolent swellings.
The hedge hyssop (Gratiola officinalis) belongs to the family Scrophulariaceae, and is a native of marshy lands in the south of Europe, whence it was introduced into Great Britain more than 30o years ago. Like Hyssopus officinalis, it has smooth, opposite, entire leaves, but the stems are cylindrical, the leaves twice the size, and the flowers solitary in the axils of the leaves and having a yellowish-red veined tube and bluish-white limb, while the capsules are oval and many-seeded. The herb has a bitter, nauseous taste, but is almost odourless. In small quantities it acts as a pur gative, diuretic and emetic when taken internally. It is said to have formed the basis of a celebrated nostrum for gout, called Eau medicinale, and in former times was called Gratia Dei. When growing in abundance, as it does in some damp pastures in Switzer land, it becomes dangerous to cattle. G. peruviana is known to possess similar properties.
The hyssop ('ezob) of Scripture (Exod. xii. 22 ; Lev. xiv. 4, 6; Num. xix. 6, 18; I Kings v. 13 [iv. 33] ; Ps. li. 9 [7] ; John xix. 29), a wall-growing plant adapted for sprinkling purposes, has long been the subject of learned disputation, the only point on which all have agreed being that it is not to be identified with the Hys sopus officinalis, which is not a native of Palestine. No fewer than eighteen plants have been supposed by various authors to answer the conditions. The most probable opinion would seem to be that found in Maimonides and many later writers, according to which the Hebrew 'ezob is to be identified with the Arabic sa'atar, now understood to be Satureia Thymus, a plant of very frequent occur rence in Syria and Palestine, with which Thymus Serpyllum, or wild thyme, and Satureia Thymbra are closely allied. Its smell, taste and medicinal properties are similar to those of H. officinalis.