DIPNOI. 2 sists of a central axis in thp fonn of a slender, tapering, jointed rod of cartilaj;o, with a row of smaller jointed rods of cartilaf;e on either side of it. This form of tin-skeleton, which occurs in certain groups of fossil tishes, as well as in Dipnoi, has been termed the archipterjgium." In respect to the structure of the soft parts, it may be noted that a cloaca is present, and the intes- tine contains a spiral valve; the heart is more complicated and highly developed than in ordi- nary tishes, and a jmlmouary artery and vein exist. The special interest in this gi^oup arises from the tielief that it anciently jjave rise to the class of amphibians. Consult: Cope. Oriyin of the Fittest (New York. 18S0) : id., Butrachia of Sorth America (Washington, 18U9) ; Gadow, Amphibia (I^ondon. 1901). See Muhfish; Stegocephaua ; and Plate of Birxoi Axi> Cin- M-EKA. DIPCENirS AND SCYl'LIS (Lat.. from Gk. A/TToiros, i'i/"/i»o.«, and ^niXXtt, Sl.'ylli.i) . Early Greek statuaries, wliose names are always as- sociated. According to Pliny the Elder, they were born in Crete about B.C. .580. Pausanias in the 'EXXdc'os nepii77')<». or Itinerary of Greece, states that they were pupils of Dfedalus. Cer- tainly their manner was that traditionally styled D;edalian, which prevailed to the beginning of the fifth century B.C.. as the result of the marked development in sculpture toward accuracy and expressiveness. At Sicyon they executed statues of the gods, intended. ai)])arently. for ornament in architecture rather than for devotional uses. Many works by them existed also at Ambracia, Argolis. and Cleon*. A group of the Dioscura* in ebony and ivory at Argolis is of particular interest as indicating Dipcenus and Scyllis as the originators of gold and ivory overlaying in statuesque art. This method reached its perfec- tion in the chryselephantine masterpieces of Phidias. Diptenus and Scyllis were also reputed to have l>een the first famous artists in marble. DIP OF THE HORIZON. See Depres.siox. DIP OF THE MAGNETIC NEEDLE. The angle between a freely suspended iiuiLMietic needle and the horizontal. It is proportioned to the vertical component of the earth's magnetism, as compared with the horizontal. At the magnetic pole the needle stands vertical : at the magnetic equator it is horizontal. Like variation, dip has periodic variations, but they are of less magni- tude than those of the variation. During the past three hundred years the dip at London has changed only about four degrees, and the daily inequalities do not exceed four or five minutes. See Magnetism, Tebrestmal; and Ixclixatiox. DIPO'LIA, OR DIIPOTLIA (Lat., from Gk. Ta AtT^Xta. Ati7r6Xta. Aii7r6€:a. from Aif. /)//, tO Zeus -f iroXifvs, polieu.i, guardian of the city, from iriXis, polix, city). An ancient Athenian festival celebrated annually on the fourteenth day of the month Scirophorion (.Tune to -Tuly) to Zeus Polieus (Zei/s rioXifut). the protector of the city. It was called Biiphonia. from the sacri- fice of an ox, which was the princijial feature of the celebration. Grain and sacred cakes were laid upon the altar of Zeus on the .Acropolis. Tien the ox. brought before the altar, began to eat the grain, he was felled with an axe by the priest, who at once fled, throwing away the axe. This was then arraigned in the Prvtanenm, and condemned to be thrown over the borders. Con- '5 DIPPER. suit llommsen, Feste der Stadt Athen (Leipzig, isys). DIPPEL, dip'pd, AxDREAs (186G— ). A Ger- man singer, born in Cassel. He was originally connected with a banking firm in Cassel, but studied music in Berlin, Milan, and Vienna, and made his first appearance in 1887 in Bremen as Pilot in The Flyintj Dutchman. Afterwards he sang in opera in London, Breslau. Vienna, and Bayreuth, and in 1890-92 and 1898-1901 in the United States. In 1902-03 he made a concert tour in the United States. DIPPEL, .ToiiANx Ko.xBAD (1673-1734). A German religious enthusiast and alchemist. He was born near Darmstadt, August 10, 1G73, studied at Giessen, lectured on alchemy in Strassbiirg, but was expelled for alleged dis- orderly conduct, and henceforth led a wandering life. Erom 1719 to 1725 he was imprisoned in the Danish fortress at Boniholm for his incau- tious remarks upon the Danish Government: then went to Swe<len, but thence he was banished through the influence of the elergj', who did not like his views. He died at Berl'eiiurg. April 2.5, 1734. He was the discoverer of Dippel's oil and Berlin blue. His writings are a mixture of her- esy and orthodoxy, piety and rationalism. Sev- eral of them he wrote under the pseudonym Christianus Democritus. For his Life, consult W. Bender (Bonn. 1S82). DIPPEL'S ANIMAL OIL (first prepared hv J. K. Dippel in 1711). One of the products o"f the destructive distillation of bones. In the crude state, it forms a thick viscid oil of a brown color, and a very disagreeable odor, but on re- distillation it may be obtained limpid and color- less. When taken internally in moderate doses it acts as an anti-spasmodic, and stimulates the vascular and nervous systems. At present, how- ever, it is no longer used in medicine. DIPTER. A common name for the constella- tion Ursa Major (q.v.). See Cn.A^BLEs's Waix. DIPPER. (1) A small, somewhat thrush- like bird of the family Cinclida-, having an al- most straight, compressed, sharp-poinfed bill; compact, waterproof plumage, and extraordinary THE .IMERICAN T>IPrEIl. habits. Dippers frequent clear, pebbly streams and lakes, feeding chiefly on mollusks and on aquatic injects and their larvae, which they seek even under water, diving with great f.aeilitv, and moving about for a short time at the hot-
