Jamtland, it is Joined with the 

 island of Froso by a bridge 1,421 

 ft.inlength. It is a centre for the 

 timber trade. Pop. 7,000. 



Ostia. Ancient port of Central 

 Italy. It was the port of Rome 

 andstood on the S. arm of the 

 Tiber, which now flows by 

 different channel farther W., 14 m 

 S W of Rome. The port is said 

 to have been founded by Ancus 

 Martius, and its emporium or har- 

 bour became a naval station, and 

 imported much wheat. Portus 

 Augusti, 2J m. to the N, on the N 

 arm of the Tiber, was founded m 

 consequence of the siting of the 

 S. channel, yet Ostia retained 

 much of its earlier imp rtan 8 c .f- 

 Modern Ostia was founded in 8, 

 bv Gregory IV. The Castello was 

 built 1483-86, but its prosperity 

 disappeared when the N. arm was 

 reopened in 1612; it is now the 

 village of Osteria near the Castello. 

 Excavations have revealed interest 

 ing details of streets, temples, 

 store-houses, and residences, 

 city had also a forum and a large 

 theatre. See Rome. 



Ostraca (Gr., hard shells). In- 

 scribed potsherds and stone slabs, 

 principally from ancient Greece 

 and Egypt. The British Museum 

 contains one of those whereby 

 Themistocles was ostracised 

 471 B.C. The name has been 

 transferred to the pottery frag- 

 ments and limestone slabs, em- 

 ployed in Egypt for ephemeral 

 ink-records. Many thousands have 



5892 



_ ^^ ^^ 



been collected, bearing Aramaic, 

 Greek, Egyptian, and Coptic 

 cords ranging from 400 B.C. to A.D. 

 900 At the Arab conquest three 

 Christians copied the Greek gospels 

 upon a series of numbered pots- 

 herds, whereof 20 remain. In li 

 Reisner found in the ruined palace 

 of Omri and Ahab at Samaria 

 about 75 potsherds with Hebrew 

 ink-inscriptions. See Graffito. 



Ostracism. Political practice 

 introduced by Cleisthenes at Athens 

 508 B.C., and subsequently 



111 UV/O u.v.j 



employed in other Greek states. 

 Once a year every Athenian citi- 

 zen had the privilege of writing on 

 an oyster-shell (ostrakon) the 

 name of any statesman whom he 

 thought it would be desirable to 

 send into exile. In the event of 

 there being 6,000 votes adverse to 

 any statesman, the decree of ban- 

 ishment or ostracism, as it came 

 to be called, took effect. The 

 period was first for 10 years and 

 subsequently for five. It did not 

 involve any loss of civic rights 

 and the victim could be recalled 

 before the end of his term of exile. 

 Noted Athenians who suffered 

 ostracism were Miltiades, Themis 

 tocles, Aristeides, Cimon, and Alci- 

 biades, by the last of whom the 

 practice was abolished. -See Gr eece. 

 Ostracoda. Order of Ento- 

 mostraca or small crustaceans. 

 The body is unsegmented and en- 

 closed in a bivalve carapace from 

 which the head does not protrude. 

 They swim by means of their 



OSTRICH 



_ 



antennae, which are jointed and 

 have brush-like terminations. In 

 some species the eggs are carried 

 about in the shells, and in others 

 are laid on water plants. Most of 

 them live in the sea, but a few 

 species are found in fresh water, as 

 the common cypris of British ponds. 

 They are all carnivorous and play 

 an important part as scavengers. 



Ostrau. Twin town in Czecho- 

 slovakia, also known as Ostrava. 

 Mahrisch, or Moravian Ostrau, is 

 on the E. bank of the Ostrawitza, 

 across which is Polnisch, or Polish 

 Ostrau, a town of the former 

 Austrian Silesia. Both are inter- 

 ested in collieries ; there are iron- 

 works, chemical, soap, and candle 

 factories E. of the river. Pop., 

 M. 0., 37,000 ; P. 0., 23,000. 



Ostrich (Struthio camels). 

 Largest living bird. Found wild in 

 Africa, Arabia, and Mesopotamia, it 

 is usually placed in the order Rati- 

 tae or running birds, the breast- 

 bone lacking the keel to which the 

 strong flight muscles of most birds 

 are attached. The wings of the os- 

 trich are small and useless for flight. 

 A fine specimen stands nearly 5 ft. 

 high at the back, and its neck 

 accounts for about 3 ft. more In 

 the male the plumage of the body 

 is black, with white plumes on the 

 wings and tail, that of the female 

 bein<* grey. The neck is covered 

 with" down. The legs, which are 

 long and strong, and part of the 

 thighs are bare, and the feet have 

 only two toes a feature peculiar 



