DITHYRAMBUS DIURETICS 151 city of Georgetown respectively. At the same time the levy court of the District of Colum- bia ceased to exist, and the District of Colum- bia became the successor of the corporations of the cities and of the county of Washington. (See GEOKGETOWN, and WASHINGTON.) DITHYRAMBUS, in Grecian antiquity, a song sung in the vintage season in honor of Bacchus. The origin of these songs is traced to the ear- liest ages of Greek civilization, and the most famed of the early composers of them was Arion of Methymna. But few fragments of ancient dithyrambic poetry remain, and it is only by tradition that we know the successes of Melanippides, Pindar, and Philoxenus in this style of composition. The dithyrambus was primitively religious ; it was lively, rapid, brilliant, and disordered, like the joy and in- toxication of a Bacchanalian festival. In the heat of improvisation, the poets often united several words into one, from which resulted expressions so voluminous and sonorous that they wearied alike the ear and the imagination. In the age of Pericles this kind of poetry wa8 the object of raillery. DITMARSH (Germ. Ditkmarschen, or Dit- marsen, i. e., the German marshes), the west- ernmost portion of Holstein, Prussia, com- prising the coast land on .the North sea, be- tween the Eider and the Elbe; area, 500 sq. m. ; pop. about 75,000. The surface is a low flat, protected against inundation by strong embankments. Excepting in the marshy dis- tricts, it has a rich alluvial soil, bearing heavy crops of wheat, beans, and hay. The inhabi- tants are a sturdy people of the primitive Teutonic type, and during the middle ages maintained a considerable degree of autonomy and equality, bravely defending their rights against the encroachments of their various rulers, German and Danish. After severe struggles Ditmarsh became part of Holstein, under Danish rule, in 1559, but continued to be governed by its own code. In 1866 it was with the rest of Holstein annexed to Prussia. DITTOS, Humphrey, an English mathemati- cian, born in Salisbury, May 29, 1675, died Oct. 15, 1715. He studied theology, and was for some years a dissenting clergyman, but subse- quently devoted himself to mathematics. Pie was encouraged by Sir Isaac Newton, through whose influence he was elected professor in the newly created mathematical school of Christ's hospital, a position which he retained till _ his death. In 1714 he published with Whiston an advertisement of a new method of finding the longitude at sea. The plan was approved by Newton, but rejected by the board of longitude; and it is said that the chagrin caused by this disappointment, and by some obscene verses of Swift, occasioned his death. He was the author of numerous mathematical treatises, among which are the following : " Of the Tangents of Curves ;" " General Laws of Nature and of Motion ;" " An Institu- tion of Fluxions;" and "The New Law of Fluids, or a Discourse concerning the Ascent of Liquids in exact Geometrical Figures, be- tween two nearly contiguous Surfaces." DIU, a Portuguese island and town of India, separated by a narrow channel from the S. ex- tremity of Guzerat, in lat. 20 43' N., Ion. 70 45' E., 160 m. N. W. of Bombay ; area, 12 sq. m. ; pop. about 10,000. The soil is unfit for cultivation and the water is brackish, but pro- visions are plentifully supplied from the main- land, with which the inhabitants carry on a lively trade. The town is situated on the E. end of the island, is well fortified, and has an excellent harbor. It was renowned in ancient times for a magnificent temple of Mahadeva, which was destroyed by Shah Mahmoud of Ghuzni about 1025. The island was taken in 1515 by the Portuguese, and was pillaged in 1670 by the Arabs of Muscat. It is at present one of the most flourishing of the Portuguese settlements. DIURETICS, drugs used to increase the amount of the urinary excretion or of some of its constituents. They may be divided into several groups: 1, those which increase the water of the urine with but little effect on its solid constituents ; 2, those which increase both the water and the solids; 3, those which increase the solid rather than the watery con- stituents ; 4, those which alter the quality without augmenting the quantity. To the first class belong squills, juniper, taraxicum, horse- radish, parsley, broom, carrot seed, spirits of nitrous ether, pure water, cantharides, and tur- pentine. Cantharides and turpentine may be given in such doses as to produce congestion of the kidneys and bloody urine. If their ac- tion is carried far enough, a suppression in- stead of an increase of the urine may result. Many salines, such as acetates, citrates, tartrates, and carbonates of soda and potassa, nitrate of potassa, and sulphate and citrate of mag- nesia, belong to the second class. Some of these salts may be given so as to pass off by the bowels, and exert but little effect upon the kidneys. In general, it is necessary to give this class of drugs in small doses, frequently repeated, when it is desired that they should pass through the kidneys and act as diuretics, and in one or two large doses when they are intended to act upon the bowels. Colchicum is the principal agent of the third class. Ac- cording to Dr. Hammond's experiments, it has a powerful effect in augmenting the amount of solid urinary constituents, while the water is comparatively little affected. The salts formed by the alkalies with carbonic and ve- getable acids render the urine alkaline when given in sufficient doses, and are consequently examples of the fourth group of diuretics. Uva ursi and chimapkila umbellata or winter- green act as diuretics in virtue of the volatile oils and tannic acid which they contain, and which pass into the urine, imparting to it a dark color and peculiar odor. Buchu, copaiba, cu- bebs, and similar substances act by virtue of
