part of Thistle’s Island to bear west, distant about six miles, and in twenty-two fathoms water, and a north-west half-west course will carry you through midway between the Horse-shoe Reef and the rocks which lay off the north-west end of Thistle’s Island, and in the direct track for Cape Donnington.  The passage between the reefs is about three miles wide, and ought not to be attempted in the night, as the tides set directly across the channel.  There is very good anchorage on the north-east side of Thistle’s Island, well sheltered three-fourths of the year.  Bring the rocks before-mentioned to bear north-north-west, and two remarkable sand hills south by west, and you will lay in five fathoms, one mile off shore—­north end Thistle’s Island west by south.  Should the wind be so strong from southwest or west-south-west, so that a vessel from the eastward cannot carry sail sufficient to fetch up to Cape Donnington, or under Thistle’s Island, it would be advisable to bear up for Hardwick Bay; passing to the eastward of Wedge Island, come no nearer to the shore of York’s Peninsula than two miles, until you arrive within five miles of Corny Point, when you may haul in for that point, rounding it a distance of half a mile, you may bring up in five fathoms, one mile from shore:  Corny Point bearing west.  Vessels from Sydney, bound to Port Lincoln, may pass through Backstairs Passage, and proceed according to the foregoing directions, or by keeping well to the southward, pass outside Kangaroo Island, until they arrive in longitude 136 degrees E., when they may shape a course either to pass between Gambier’s and Thistle’s Islands, or else for Cape Catastrophe, taking care to give the Neptune Islands a wide berth, and then proceed according to either of the foregoing directions.”

To this extract which refers exclusively to the navigation of Spencer’s Gulf, I may add, that Boston Island lies immediately opposite to the bay, and that there are two channels of entrance round the island, through which vessels of the largest size can pass with any wind or in any weather, for the harbour is so sheltered by the headlands forming the entrance, that the swell of the sea is broken before reaching it.

The high ground which almost surrounds Boston Bay, protects it in like manner from the winds, more especially those coming from the west and southwest, in which directions some of the hills attain the height of several hundred feet.

The depth of water in the central parts of the Bay is about twelve fathoms, varying from five to seven at the distance of less than a quarter of a mile from the shore all round; whilst at Boston Point, where the town of Boston has been laid out, there is a depth of two, three, and four fathoms, at about a boat’s length from the land.  The bottom consists in some places of mud, in others of shells and sand, so that the anchorage is safe.

The tide sometimes rises seven feet, but that is considered a high tide, the ordinary rise not being more than five; this depends, however, on the outward state of the Gulf, and the quarter from which the wind may happen to be blowing.