rate easily. It is also green and fluted, and there is so much silica in the epidermis that the plants feel rough. It is on this account that the name scouring rush is sometimes used. Foliage leaves have been abandoned, but minute scale-leaves form sheaths at each joint. The stems are sometimes simple, at other times they branch profusely, but they are always green, since they do leaf-work. At certain times a cone-like structure, the strobilus, appears at the top of the stem, which bears the sporangia containing spores. Horsetails are found in wet ground or in very dry ground. Slender branching forms are very common along the sandy embankments of railroads. See Pteridophytes.
Era of Good Feeling, a name given to the period in American political life from 1817 to 1824, during which there practically was only one party—The Democratic-Republican. The Federalist party had almost disappeared by the end of the War of 1812, so that in 1821 President Monroe was re-elected by an electoral vote of 231 out of 232. Differences of opinion regarding public works and the tariff question soon afterwards brought the era of good feeling to a close. By some historians the period is restricted to the second term of Monroe's administration.
Erard (ā̇r′ār′), Sebastien, a French inventor and maker of musical instruments, was born at Strassburg, April 5, 1752. Going to Paris at sixteen, he started in business as a maker of pianos, completing his first one in 1776 or 1777. This was one of the earliest pianos made in France. He was soon considered the best pianoforte maker in Europe. The French Revolution drove him to London, where he established a factory. The grand piano was his invention, with a double-action harp and many other valuable improvements in the making of both pianos and harps. His pianos still have a reputation. He died at Passy, near Paris, Aug. 5, 1831.
Eras′mus, Desiderius, a Dutch scholar and philosopher, was born at Rotterdam, according to the date on his statue, in 1467. His guardians tried to induce him to enter a monastery, in order to obtain his property, and Erasmus, to please them, agreed to attend the Augustinian College of Sion, near Delft, where for six years he led the life of a monk. This life probably made him the bitter and sarcastic enemy of the monks that he was during the remainder of his life. He studied and taught in Paris till 1498. Among his pupils was Lord Mountjoy, at whose invitation, probably, he made his first visit to England, in 1498. He spent his time there mostly at Oxford. Six years spent in Paris give us the Adagia, a collection of Greek and Latin proverbs, and the Christian Soldier's Dagger. Another visit to England was made at the accession of Henry VIII, and on this journey he planned his Praise of Folly, a satire on kings and monks. He was professor of divinity and also of Greek, at Cambridge, for the next few years. In 1519 appeared his most famous work, the Colloquia, a series of talks on everyday subjects, the sharpness and boldness of which did much to prepare the minds of the people for the work of Luther. In 1516 his edition of the New Testament in Greek, the first published Greek text, appeared. He also edited scores of Greek and Latin texts. When the Reformation came, Erasmus stood between the two parties, and the last years of his life were spent in a long dispute and struggle with the friends and foes of the new religion, neither of whom he satisfied. In spite of these troubles, he enjoyed fame and consideration beyond that of any man-of-letters before or since. He died at Basel, Switzerland, July 12, 1536. See Essays by Milman, Life by Drummond, Letters edited by Froude and Life by Emerton.
Er′ebus, Mount, an active volcano in Victoria Land in the Antarctic regions. It was discovered by Ross in 1841, and named after one of his ships. It is 12,367 feet in height, and is the nearest volcano to the South Pole.
Erfurt (ĕr′fŏŏrt), a city of Prussian Saxony and the ancient capital of Thuringia, is thirteen miles from Weimar. Its two citadels once were monasteries. It was a strongly fortified city until 1873, its position on the central road through Europe giving it importance. Its cathedral, one of the oldest Gothic buildings in Germany, has very fine sculptures and bronze castings, one especially, a Coronation of the Virgin, which dates from the 16th century. The Augustine monastery, known as the home of Martin Luther, is now called the Martinsstift (Martin's Institute), and is used as an orphan asylum. The growing of flowers and vegetables and the raising of flower seeds are two of the principal industries. There also are manufactures of woolen, silk, cotton and linen goods, lamps, machines, shoes and beer. It was made a bishopric in 741. Since 1803 it has belonged to Prussia, except during 1806-14. The congress of Erfurt, held in 1808, was attended by Napoleon, the emperor of Russia and several princes of Germany. Population, 111,461.
Erg, the unit of work employed in physics and chemistry. It is defined as the amount of work done by a force of one dyne when exerted through a distance of one centimeter. It requires forty-two million ergs of work to heat one gram of water one degree centigrade, that is,
1 calorie = 42×10⁶ ergs, very approximately.
Er′got, a very astringent drug, obtained from a certain phase (the sclerotium) of a
