384 EXPEDITION TO JAPAN. 



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, &c, neither can be relied upon. 



Should Oho-sima be obscured by thick weather before reaching Cape Diamond, endeavor to 

 si°dit Kock island, for there are no very conspicuous objects on the main land by which a 

 stranger can recognize the harbor at a distance, and the shore appears as one unbroken line. 



To the westward of the harbor there are several sand beaches, and three or four sand banks. 

 These can be plainly discerned when within six or eight miles, and are very good land-marks. 



A vessel from the southward and eastward should pass to the westward of the island of Kozu- 

 sima,* which may be known by a remarkable snow-white cliff on its western side. There is 

 also a white patch on its summit to the northward of the cliff. From this island the harbor 

 bears N. by W. f W., distant about 26 miles. 



Approaching from the eastward, the harbor will not open until you get well inside of Cape 

 Diamond. 



To the northward of Cape Diamond is the bay of Sirahama, which is quite deep, and, as it 

 has several sand beaches, it may be mistaken for Simoda ; but as you approach this bay, Cape 

 Diamond will shut in the Ukona rocks and Rock island to the southward, while in the Simoda 

 roads they are visible from all points. 



There are but two hidden dangers in the harbor ; the first is the 



SOUTHAMPTON ROCK, 



Which lies in mid-channel, bearing N. \ W. from Vandalia bluff, about three-fourths of the 



way between it and Centre island. This rock is about 25 feet in diameter, and has two fathoms 



water upon it. It is marked by a white spar-buoy. 



The second is the 



SUPPLY ROCK, 



Bearing S. by W., a short distance from Buisako islet ; and is a sharp rock, with 11 feet water 

 upon it. Its position is designated by a red spar-buoy. 



Both of these buoys are securely moored ; and the authorities of Simoda have promised to 

 replace them should they, by any cause, be removed. 



Centre island, which receives its name from being the point from which the treaty limits are 

 measured, is high, conical, and covered with trees. A cave passes entirely through it. 



In the outer roads, or mouth of the harbor, a disagreeable smell is sometimes experienced. 

 But inside of the Southampton rock and Centre island vessels are well sheltered, and the water 

 comparatively smooth. Moor with an open hawse to the southward and westward. 

 There are good landings for boats in Simoda creek, and at the village of Kakisaki. 

 A harbor-master and three pilots have been appointed. Wood, water, fish, fowls, and eggs, 

 also sweet potatoes and other vegetables, maybe procured from the authorities. It is necessary 

 to supply them with casks to bring the water off. 



Latitude of Centre island 34° 39' 49" N. 



Longitude " 138° 5*7' 3 0" E. 



Variation f ■••• 2° 55' westerly. 



High water F and C V. hr. 



Extreme rise of tide 5 feet 7 inches. 



Mean " 3 feet. 



"This is the most southwestern island of the chain of islands lying off the Gulf of Yedo. 

 f The variation given on the chart of Simoda is incorrect. 





