794 



ZANZIBAK. 



at both ends, with curves extending far toward 

 the midship-section. She draws 3 feet at the 

 bow and 4 feet at the stern. A deck, slightly 

 arched fore and aft, covers the whole boat. 

 The engine is a compound condenser, with 12- 

 inch stroke, and cylinders 12 and 21 inches in 

 diameter. The boiler is similar in principle to 

 the ordinary Herreshoff boiler, but differs in 

 some details, the tubes being arranged hori- 

 zontally in sets immediately over the fire, each 

 set being at right angles to that just above it. 

 The fire-box 6J feet square. A common pump 

 carries the water of the exhaust from the con- 

 denser to the upper set of boiler-tubes, and 

 through the boiler to a separator in its imme- 

 diate front, with which the steam-pipe is con- 

 nected. The estimated limit is 450 horse- 

 power, but in passing some of the swiftest 

 steamers only 125 pounds of steam was used, 

 while the boiler will work safely at 160 

 pounds. The screw is four-bladed, with 6 

 feet pitch. The builders claim that she is the 

 fastest steam-vessel in existence. 



Ice-yachting has, within a dozen years, be- 

 come a popular winter pastime. The Hudson 



FIG. 7. 



river, between Newburg and Albany, is most 

 favorable to the sport, and there the ice-boat 

 has reached its highest development. In con- 

 struction these yachts are simple, but they re- 



quire strong and careful workmanship. The 

 ordinary rig is a jib and mainsail, but the cat- 

 rig is used to some extent, and recently the 

 lateen, with u shear " or double masts, as 

 shown in Fig. 6, has been tried with fair 

 success. Ice-yachts are always manoeuvred, 

 whether on or off the wind, with the sails 

 trimmed flat aft. The friction of the run- 

 ners when under headway is so slight that it 

 need not be considered at all, and the main- 

 sheet need not be started in order to attain a 

 speed equal to that of the wind when running 

 free. On the wind the case is different, and it 

 is here that the ice-yacht attains its tremendous 

 velocity, outstripping the wind that drives it 

 The possibility of its doing this is always ques- 

 tioned by those who have not given the matter 

 attention, and a diagram (Fig. 7) is appended 

 in demonstration. It must be borne in mind 

 that the runner- friction, when a moderate 

 speed is attained, is inappreciable, but the pas- 

 sage of frame and top-hamper through the air 

 at a high speed amounts, of course, to a con- 

 siderable item. In the diagram the arrow 

 shows the direction of the wind blowing at 

 right angles against the sail, d. The boat D 

 is supposed to be steering a straight course 

 from A to C. A moment's consideration will 

 show that, if the elements of air- and ice-fric- 

 tion could be eliminated, the boat would move 

 from A to while the wind was passing over 

 a distance equal to A B. In point of fact, it 

 can not literally do this, owing to mechanical 

 imperfections, but it approximates the result 

 indicated, and, under exceptionally favorable 

 conditions, has attained a speed estimated as 

 high as 80 or 100 miles an hour, the wind at 

 the time not blowing more than 30 or 40 miles 

 an hour, and probably far less than that. Of- 

 ficial records of runs over measured distances 

 have frequently exceeded a mile a minute. 



Z 



ZANZIBAR, a monarchy occupying the island 

 of Zanzibar in the Indian Ocean, and the oppo- 

 site coasts of the Continent of Africa. The 

 reigning sovereign is Sultan or Seyyid Bargash 

 ben Said, who succeeded his brother Madjid, 

 Oct. 7, 1 870. The British Government induced 

 Seyyid Bargash to sign a treaty promising to 

 suppress the slave-trade within his dominion?, 

 which he has endeavored to execute. He has 

 been guided in his policy by British influence, 

 exercised through the English consul-general, 

 Sir John Kirk. 



Zanzibar is economically a dependency of 

 British India. Indian trade has been estab- 

 lished there from early times, and Indian sul- 

 tans formerly ruled on the coast of the main- 

 land. In 1784 the island became a province of 

 the Sultan of Muscat. In 1856 it became in- 

 dependent by the intervention of the Indian 

 Government. In 1861 the Indian Viceroy ar- 

 ranged terms with the Sultan of Muscat by 

 which the latter receives an annual sum from 



the Indian exchequer in lieu of tribute from 

 Zanzibar, which the Indian Government re- 

 ceives back from the Sultan of Zanzibar in pe- 

 riodical payments. Bargash ben Said, who was 

 at that time in Bombay, a fugitive from his 

 relatives, was recognized as heir to the throne 

 at the dictation of the Indian Government. In 

 1862 the independence of Zanzibar was guar- 

 anteed by Great Britain and France. In 1884 

 it was recognized at the African Conference in 

 Berlin. The trade and revenue of Zanzibar 

 have greatly increased, and the political and 

 military organization of the sultanate have 

 been to a great extent developed, during the 

 reign of Seyyid Bargash. His army was or- 

 ganized and is commanded by Gen. Matthews, 

 an English officer. Of late years, since the 

 English Government ceased to encourage politi- 

 cal reliance on England, Germany and France 

 have sought to acquire influence in Zanzibar. 

 Statistics. The area of the island is 1,590 

 square kilometres; that of the neighboring 



