In several Museums we see human heads injected, and preserved in oil of turpentine. The anatomical collection of the Museum of Natural History in Paris possesses a head prepared in this way more than a hundred years ago, by the celebrated Ruitch, a Dutch physician. It still preserves all the vivacity of its colours. The cold so far affects the liquor in which it is contained, as to hide it completely, but at the return of spring the liquor becomes clear, and we distinguish the object perfectly.

Without doubt all these preparations are very useful to science, and are even necessary to the demonstrations of professors. Human skeletons are more so, and since the bony part of our body is the only one which we are able to preserve entire and in its natural position, we will try to describe the different methods employed for this purpose in the present day.

According to the methods which they use, anatomists distinguish two sorts of skeletons; one which they call natural, and the other artificial; and these two methods are sufficient to obtain the skeletons of all animals.

Of Natural Skeletons.

This first manner is the easiest and most general;

is to say, of the size of a fox. Skin the animal, take away its flesh, separating the head only, to take out the brain more easily by the occipital hole. When the flesh is separated from the bones, put the whole of the skeleton to macerate in a vessel of water, with a little quick-lime added, which has the property of whitening bones. After two or three days' maceration, the skeleton is extended on a table, and by the aid of a scalpel all the remaining flesh is scraped off. If the solid parts adhere too much, the skeleton is again put to macerate, until the bones are completely cleaned, taking every precaution to preserve all the ligaments which fasten the bones one to the other. These ligaments acquire much consistence when they are dry, and are sufficient to keep the skeleton upright, when it is a small animal. If there be any reason to suspect that they will not, an iron wire is passed longitudinally through the vertebral column from the end, which must pass out anteriorly, to fasten the head to the cervical vertebræ. Two forks are formed, the one to support the anterior part, the other for the posterior: for this two pieces of iron wire are taken, the height of the animal; they are twisted together, leaving a fork at each extremity, and are both fastened on the board destined to receive the skeleton. The one ought to pass, or enter, the ribs, and encompass the vertebral column between the shoulder blades; the other between the bones

of the pelvis. Notwithstanding these precautions, it sometimes happens that pieces of the skeleton detach one from the other; in this case two holes are pierced in the separated ends of the bones, and they are re-united with fastenings of brass wire. Such is the method employed for the skeletons of reptiles, fish, birds, small mammalia, and children.

Of Artificial Skeletons.

The skeletons of men and animals of middling size cannot be set up in the manner last described, and more skill is required to form them. We begin, in the same way as for the natural skeleton, by taking off as much of the flesh as possible, but we must separate all the bones at their joints, before putting them to macerate: on account of their greater size they ought to remain longer in the water. We renew the scrapings until they are perfectly cleaned; then expose them to the sun to whiten, and take care to turn them every day. The most difficult part of the operation follows, which is to re-assemble all the bones, to re-unite them, and to place them in their natural position. Beginning by one of the extremities we make holes at the apophysis *, by the help of a wimble, or a lathe; sometimes with the

The apophysis is the ball or round end of the bone,

gimblet. Fasten all the bones with an iron or brass wire, which we pass through the holes already bored. Twist the two ends of the wire, leaving a little play between the articulations, and pursue this method until the whole skeleton is mounted. We then procure a flat piece of wood to place it on, and keep it erect by means of two iron uprights, such as we have described for the natural skeletons.*

The links of wire above mentioned are insufficient to unite all the bones of large-sized animals, such as the horse, the ox, the camel, and the elephant. We substitute two iron pegs, with a head at oǹe end and a screw at the other; each screw must have a nut, and each pair of screws must be accompanied by a plate of iron, narrow, and pierced at each end, to pass the screw through. screw through. We will now suppose ourselves about to unite the bone of the thigh to that of the leg of a large quadruped. We pierce a hole at about two inches from its extremity, we do the same with the leg-bone, bring the two together, and passing one of our screws (longer by an inch than the bone is thick) into the hole of one of the above-mentioned plates, then through the bone,

* See the drawing of one of the specimens in the Gallery of Anatomy, plate I., the wires in which are coloured red, to distinguish them. I have removed the head a little too far from the cervical vertebræ, to show the course of the wire which joins them more clearly.

and lastly into the other plate, we tighten them by the aid of the nut; doing the same by the leg-bone, the two parts will be united and supported by the two plates, which are retained by the iron pegs or screws, and the play or space between the two extremities of the bones will have been provided for, by the distance left in piercing the holes for passing the pegs through.

As these vast frames are more often set up for instruction, than for the gratification of mere curiosity, it is customary to saw the head longitudinally in two, except the under jaw; the re-union of the parts is effected by an iron hinge, which permits them to be opened at pleasure, for the study of the interior of the head.

Monkies.

In all systems monkies are placed immediately after man.

Before we begin to skin an animal, we must fill its mouth with flax; if there be any wound capable of letting out the blood, cotton or tow must also be introduced into it. This done, we stretch out the animal on its back, and taking precisely the middle

* See fig. 2. plate 1.; a. is the iron plate, b. is the nut which tightens the screw of the iron peg, c. is the head of the second iron peg, the nut and screw of which, similar to the first, is of course on the other side.

B