A number of birds usually came on board the brig towards evening, to roost, most of which appeared to me to be land-birds. The colours of some were very beautiful, and in many we could trace a resemblance to our small ducks, magpies and larks. When to the north-east of the Arru Islands we obtained soundings, for the first time, on a corally bottom; but as we stood to the south-west the depth gradually decreased, the bottom changing from coral to sand, and from sand to soft mud. We encountered daily an immense number of large Noord-kapers (a species of whale), which collected around the brig, and on two occasions one of these sea-monsters passed under her bottom, grazing the keel, and shaking the entire vessel. At noon, on the 26th, we passed over a small patch of hard sand, on which we had only nine fathoms, the depth around being nineteen and twenty fathoms mud. This, which was named Kolff Bank, was found to lie in latitude 7 deg. south, longitude 136 deg. 4 min. east.[45] On the night of the 27th, while steering to the south-south-east, the depth gradually decreased, but the bottom still continued muddy. This made me suspect that we were approaching False Cape, (or Cape Valsche), the south-west extreme of New Guinea. On steering south the depth increased to twenty-six fathoms, but after hauling up north-east and east-north-east we had only five and six fathoms, which, coupled with a swell from the south and south-east, led me to conclude that we had passed the Cape. In the evening, when the atmosphere cleared up, we saw the land to the northward, and soon brought up to await the day. During the night we experienced north-east winds, with heavy rain, and a current of six miles from the east-south-east. Rise and fall between seven and eight feet. As opportunity offered, we stood in and out from the shore--never being able to approach nearer than eight miles, the depth at that distance being only three fathoms, but further to seaward it increased very rapidly, the first cast of the lead, when standing off the edge of the bank, giving five fathoms. The land was everywhere low, and covered with large trees. I endeavoured as much as possible to approach the land, either with the brig or with the boats, but was always prevented by the mud-bank. Between the Cape and St. Bartholomeus River, we saw no opening that would admit our entrance. Having arrived off the mouth of the St. Bartholomeus River, which is easily distinguished, as the points forming the entrance are a considerable distance apart, the unfavourable state of the weather, coupled with an increasing swell raised by the strong south-east wind, determined me to return towards False Cape; being the more inclined to do so, from the brig, which was anchored nine miles from the shore, rolling heavily, from being forced by the tide to lie across the swell, and having already carried away several of the shrouds of the lower rigging.