EMBEB DAYS EMEBAXD acts of a similar nature were passed during the War of 1812. The plan of limiting commercial intercourse by em- bargo, non-importation and non-inter- course acts was called the "restrictive system." In the course of the World War (1914-1918) attempts were made by pro-Germans, pacifists, and well- meaning humanitarians to place an em- bargo on the shipment of arms to En- tente nations, but the attempt failed. EMBER DAYS, certain days set apart for prayer and fasting, one special theme of supplication being that the blessing of God may descend on the crops, and consequently that there may be plenty in the land. Stated days of this character began to be observed in the 3d century, but at first there was no unity over the Christian world as to the precise days. In A. D. 1095 the Council of Placentia diffused them over the year. EMBROIDERY, the art of producing ornamentation by means of needlework on textile fabrics, leather and other ma- terials. Embroidery is closely allied to lace-work, which is the direct develop- ment of the cut, drawn, and embroidered linen of the classic and early Christian periods. Embroidery pure and simple does not admit of applique, which, in conjunction with embroidery, forms a separate art in itself; nor should it be confused with tapestry work, which is to weaving what lace-work is to embroid- ery. Embroidery has had many schools and styles, but it may be classed under six general heads : 1. Linen embroidery, embracing all work done on linen or cotton in threads of the same color as the textile, and where the ornamentation is dependent wholly on the fineness of the needlework and the form nf the design for its beauty. This work includes cut work and drawn work, to the point where netlike inter- weaving of the embroidery threads be- comes lace. 2. Linen embroidery in color. — Linen and cottons are embroidered in colors with either silk, cotton, or wool. This work includes most of the Oriental work, where the colored design produces the ornament, and fine needlework and for more secondary considerations to the disposition of color. This work in fine wool reaches its highest excellence in the India shawls, which are the nearest bond between embroidery and weaving. 3. Gold and silver embroidery, in which threads and spangles are sometimes used in addition to the metal threads. The Italians and Spanish of the 16th cen- tury, and the Orientals (notably the Japanese), have done much in this class of work. . 4. Silk, gold and wool. — This sty!'. reached its highest excellence in the ec- clesiastical embroideries of Europe in the 15th and 16th centuries. 5. Silk and wool embroidery on coarse canvas, where the foundation textile is entirely hidden by the regular inter- woven stitches. This work often so nearly resembles certain tapestries as to cause confusion in distinguishing them. 6. Modern imitations in coarse mate- rials of the fine work of the past, and the development of those imitations known variously as crewel work, tapestry work, etc. EMBRYO, an unborn young animal, or the rudimentary young plant, espe- cially when within the seed. The term foetus is equivalent to embryo, but is re- stricted to mammalian development. The term larva is also applied to a young animal which is more or less markedly different from the adult form. EMBRYOLOGY, that department of biology which traces the development of the individual organism before birth. It gives the history of the organism from its earliest individual appearance till it is born or hatched, properly including all the anatomical and physiological changes that take place in the embryo, whether in the uterus or the Q?:^. The investigation necessarily takes two forms; a description of the successive structural stages, and an analysis of the vital processes associated with each step. The development of the chick was watched in Greece 2,000 years ago by Aristotle and Galen; and in 1651 Harvey sought to establish two main propositions: (1) that every animal was produced from an ovum, and (2) that the organs arose by new formation (epigenesis) , not from the expansion of some invisible prefor- mation. But as a systematic science embryology dates from the 19th century. Wolff in 1759 reasserted Harvey's epi- genesis, and showed that the germ con- sisted of almost structureless material, and that the process of development was a gradual organization. In 1817 Pander took up Wolff's work virtually where he left it. He was immediately re-enforced and soon left behind by Von Baer, whose investigations laid a firm foundation for modern embryology. Since the estab- lishment of the cell-theory in 1838-1839. and the now well-known facts that the organism starts from a fusion of two sex-cells, and that development consists in the division of the fertilized ovum and differentiation of the results, progress has been rapid. EMERALD, a variety of beryl, dis- tinguished from the latter by being emerald-green in place of pale green.