In tacking about between the Bank Chico and Ortiz, you can, as before said, run your tacks upon all the points of the Bank Ortiz as long as you are in 3 fathoms water. But in the tacks which you run upon the Bank Chico, you must put about ship as soon as the sounding line does not give you more than 4 fathoms, because this bank is full of pointed rocks, particularly at the place where the second buoy is placed, upon the point from the N.W. to the S.E.; it is also equally rocky from the first buoy to the S.E. as far as three miles to the W.N.W. because on the two points you find no more than 1½ fathom water.
Positions of the Ten Buoys placed on different Banks in the River Plate.
Upon the Bank Chico there are Four Red Buoys.
1st. Is placed at the S.E. extremity of the Bank Chico, on a bottom of 3 fathoms. From this Point, you make the Magdalene Church at the S. 15° W. of the compass.
2d. Is placed at the S. extremity of the Bank, on a bottom of 3 fathoms. It is situated at the W. ¼ N.W. of the first, distant 4 miles: you make the Church, at 15° E.
3d. Is situated to the N. ¼ N.W. of the second, distant 4 miles, upon a bottom of 1½ fathom; it is in the middle of the Bank. You make the Point of Atalaya to the S.W. of the compass.
4th. Is placed at the N.W. extremity of the Bank, on a bottom of 3 fathoms, to the W.N.W. of the third, distant 4 miles. You make the Point of Atalaya to the S. 24° W. of the compass, distant 10½ miles.
Upon the Bank Ortiz are placed Four Black Buoys.
1st. Is at the S.E. extremity of the Bank Ortiz, on a bottom of 3 fathoms. From the buoy, you make Cape Indian to the S.W. ¼ S. of the compass: you will, at the same time, see, from the deck of a vessel of an ordinary size, and on a clear day, the buoy, and the coast of Cape Indian.