This naturally originates the question—­to what extent do the Louisiade Archipelago and the south-east coast of New Guinea afford a field for commercial enterprise?  What description of trade can be established there by bartering European goods for the productions of these countries?  Unfortunately at present most of the evidence on this point is of a negative kind.  Besides articles of food, such as pigs, yams, and coconuts, and weapons and ornaments of no marketable value—­tortoise-shell, flax, arrowroot, massoy bark, and feathers of the birds of paradise were seen by us, it is true, but in such small quantities as to hold out at present no inducement for traders to resort to these coasts for the purpose of procuring them.  That gold exists in the western and northern portions of New Guinea has long been known, that it exists also on the south-eastern shores of that great island is equally true, as a specimen of pottery procured at Redscar Bay contained a few small laminar grains of this precious metal.  The clay in which the gold is embedded was probably part of the great alluvial deposit on the banks of the rivers, the mouths of which we saw in that neighbourhood, doubtless originating in the high mountains behind, part of the Owen Stanley Range.

It is evident, however, that our acquaintance with the productions of a great extent of coastline upon which we never once landed must be very slight, but with that little we must be content until some more complete exploration of the shores, which were only cursorily examined, and especially of the rivers of the Great Bight—­which seem to offer a ready means of penetrating far into the interior of New Guinea—­shall have been effected.  That an expedition with this end in view will soon be undertaken is, however, highly improbable, the survey of the Rattlesnake having completed all that was requisite for the immediate purposes of navigation in those parts.

GEOLOGICAL REMARKS.

The fact of the existence of several active volcanoes on islands immediately adjacent to the north coast of New Guinea (first made known by Dampier) and the circumstance of volcanic bands traversing the length of many of the great islands of the Malayan Archipelago, and others as far to the southward as New Caledonia and New Zealand, rendered it extremely probable that we should have found indisputable signs of comparatively recent volcanic action in the south-east part of New Guinea.  We saw no volcanoes, however, and the great central mountain chain appeared to me to be probably granitic.  The large Brumer Island is composed of igneous rocks as formerly mentioned; and at Dufaure Island I obtained from some canoes which came off to us a few smooth water-worn pieces of hornblendic porphyry.  Some specimens of obsidian, or volcanic glass, were also procured from the natives at the latter place, where sharp-edged fragments are used for shaving with; one variety is black, another of a light reddish-brown,