The most important practical result of Captain Stanley's survey of the Louisiade Archipelago and the south coast of New Guinea, was the ascertaining the existence of a clear channel of at least 30 miles in width along the southern shores of these islands, stretching east and west between Cape Deliverance and the north-east entrance to Torres Strait--a distance of about 600 miles. This space was so traversed by the two vessels of the expedition without any detached reefs being discovered, that it does not seem probable that any such exist there, with the exception of the Eastern Fields of Flinders, the position and extent of which may be regarded as determined with sufficient accuracy for the purposes of navigation, and the reefs alluded to in Volume 1, which, if they exist at all, and are not merely the Eastern Fields laid down far to the eastward of their true position, must be sought for further to the southward. The shores in question may now be approached with safety, and vessels may run along them either by day or night under the guidance of the chart--without incurring the risk of coming upon unknown reefs, such as doubtless exist in other parts of the Coral Sea further to the southward--judging from the occasional discovery of a new one by some vessel which had got out of the beaten track. Whalers will no doubt find it worth their while--with the characteristic enterprise of their class--to push into those parts of the Coral Sea now first thrown open to them, and, although we have not as yet sufficient grounds to warrant the probability of success in the fishery, yet I may mention that whales were seen on several occasions from both of our vessels. USEFUL PRODUCTIONS OF NEW GUINEA. 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.