1282. The dung of sea-birds has never till lately been much used as a manure in this country; but it is probable that even the soil of the small islands on our coast much frequented by them would fertilise. Some dung of sea-birds, brought from a rock on the coast of Merionethshire, produced a powerful, but transient, effect on grass. The rains in our climate must tend very much to injure this species of manure, where it is exposed to them soon after its deposition; but it may probably be found in great perfection in caverns or clefts in rocks haunted by cormorants and gulls. Some recent cormorants' dung, when examined, had not at all the appearance of guano: it was of a greyish-white colour; had a very fetid smell, like that of putrid animal matter; when acted on by quicklime, it gave abundance of ammonia; treated with nitric acid, it yielded uric acid.