It is to these, and some other animals nearly allied to them, that we are indebted for the drug or perfume called _ambergris_. This is generally found in the stomach, but sometimes in the intestines, and in lumps from three to twelve inches in thickness, mixed with many substances very different from itself, such as macerated vegetables, the remains of marine shell-animals, the bones and other hard parts of fish; and the ambergris itself frequently contains the beaks or jaws of different species of sepiæ, or cuttle-fish. The latter are the cause of those yellowish, whitish, or dusky spots that are often observable in this drug. As we see it in the shops, ambergris is an opake substance, which varies in solidity, according to its exposure to a warm or cold atmosphere. It is however, in general, sufficiently hard to be broken. Its smell is extremely powerful and agreeable to some persons, but unpleasant and even nauseous to others. When first taken from the stomach or intestines of the animals which produce it, ambergris is quite soft to the touch; and, as may well be conjectured from the situation in which it is found, has a fetid and most disgusting smell; but after it has, for some time, been exposed to the influence of the atmosphere, it becomes harder, and yields the powerful and peculiar odour by which it is characterized. Oil, spermaceti, and ambergris, are supposed to be yielded in greater or less quantity from every species of cachalot. 121. _The COMMON or TRUE DOLPHIN_ (Delphinus delphis) _is a cetaceous animal nine or ten feet in length, with a row of large teeth in each jaw, and a single orifice near the top of the head; an oblong and roundish body, a fin on the back, and the snout narrow and pointed, having a broad transverse band or projection of the skin on its upper part. The body is black, with a bluish tinge above, and white below._ _Dolphins are found in nearly every part of the ocean._ Few animals have had greater celebrity than these. Their activity in playing about near the surface of the ocean, their undulating motion, and the evolutions and gambols of whole shoals of them together, occasionally afford to mariners and others a very entertaining spectacle. By the ancient Greeks and Romans dolphins were supposed to entertain a kind of friendship towards mankind, and were consecrated to the gods. In cases of shipwreck they were believed to be in waiting to rescue and carry on shore the unfortunate mariners. Pliny, the Roman naturalist, was credulous enough to believe that dolphins had been rendered so tame as to allow of persons mounting on their backs, and being carried in safety over a considerable space of sea. As these animals, in their progress through the water, often assume a crooked form, in order to spring forward with the greater force, both ancient and modern artists have depicted the dolphin with its back curved.