416 EXPEDITION TO JAPAN. 



they generally appear as one. The larger reaches a height of seventy feet. Between these 

 rocks and Kock island there is a ciirrent setting east northeastwardly, and running at a rate of 

 quite four miles an hour. From Rock^ Centre island, so called from its being the point from 

 which the treaty limits are measured, bears N. ^ E., at a distance of five and a half miles, and 

 from the two Ukona rocks, N. by E. ^ E., distant three and a half miles. Centre island is 

 high, conical in shaj^e, and is covered with a full growth of trees, while through its base passes, 

 from one side to the other, a natural cave. Its latitude was found, by careful observation, to be 

 34° 39' 49" N., and its longitude 138° 51' 50" E., with a variation of 52' westwardly. High 

 water, full and change, five hours. The extreme rise of the tide is five feet seven inches upon 

 the shores of the island, and the mean rise three feet. Buisako is the name of an islet which, 

 covered with trees and shrubs, and about forty feet in height, lies N.N.E. from Centre island. 

 Off the village of Susaki, at a distance of one-third of a mile from the shore, is a ledge of rocks 

 upon which the swell is always breaking. 



Vessels bound to the harbor of Simoda from the southward and westward should make Cape 

 Idzu, latitude 34° 32' N., longitude 138° 51' E., from which Rock island bears E.S.E. i E., 

 distant about six miles. If the weather is at all clear, the chain of islands at the entrance of the 

 lower bay or gulf of Tedo will, at the same time, be plainly visible. Between Rock island and 

 the main land there are a number of rocks projecting above water, among which the Japanese 

 junks freely pass ; but a ship should not attempt the passage inside the island, unless in case 

 of urgent necessity, as the northeasterly current, which sweeps along this coast, seems to be at 

 this point capricious both in direction and velocity. Griving Rock island the berth of a mile, 

 the harbor of Simoda will be in full view, bearing N. ^ W., distant five miles. Vandalia bluff, 

 on the east side of the entrance, may be recognized by a grove of pines on its summit, and 

 the village of Susaki, which is situated about one-third of the way between the bluff and a 

 sharp point called Cape Diamond, making out to the eastward of the entrance to the harbor. A 

 vessel standing in from Rock island will probably pass through a number of tide-rips, but 

 soundings will not be obtained by the hand-lead until near the entrance of the harbor, when 

 the navigator will find himself in from seventeen to twenty-four fathoms. Should the wind be 

 from the northward and fresh, it would be expedient to anchor at the mouth of the harbor until 

 it lulls or shifts, or until the vessel can be conveniently warped in, as the breezes usually blow 

 in flaws and are always baffling. 



Approaching from the northward and eastward, a vessel can pass on either side of the island 

 of Oho-sima, from the centre of which Cape Diamond bears W.S.W. | W., distant about 

 twenty miles. The navigator approaching from the east will not find the harbor opening until 

 he is well inside of Cape Diamond. Between Oho-sima and Simoda no dangers are known to 

 exist, but the northeasterly current must be borne constantly in mind, particularly at night 

 and in thick weather. Its general strength is from two to three miles per hour; but as this, as 

 well as its direction, is much influenced by the local winds, headlands, islands, rocks, and other 

 causes, neither can be relied on. 



Should Oho-sima be obscured by thick weather before reaching Cape Diamond, the pilot should 

 endeavor to sight Rock island, for there are no very conspicuous objects on the main land by 

 which the stranger can recognize the harbor at a distance, and the shore appears as one 

 unbroken line. To the northward of Cape Diamond is the bay of Sira-liama, which is quite 

 deep, and as it has several sand beaches it may be taken for Simoda ; but as this bay is 



