2d. _Models in wax_, nearer to nature than plates, reproduces objects with admirable truth for the eye, but for the eye only. They were recently estimated of such importance, that courses on modelling were introduced into the schools in many cities of France; nevertheless, it cannot be concealed that pieces thus prepared leave much to be desired: 1. The relations of the organs which they indicate are very limited: 2. It is necessary then to multiply them to infinity, if it be desirable to represent under various points of view, the different points of the human body, which is indispensable, in order to comprehend their relations and connections: 3. And still the mind comprehends with difficulty the totality of objects viewed in a great number of pieces: 4. They cannot be handled and displaced as is requisite for study, without injury to them. 3d. _Artificial pieces_, which possess many of the inconveniences of wax models, are more proper to give a knowledge of the parts, which enter into the structure of man; nevertheless, if they be white wood, like the subjects of Fontana, or in Carton, like those of Ameline, or of M. Azoux,[8] they leave much to be learned of the properties which are requisite to an accurate and complete knowledge of the parts. Finally, these three means of communicating knowledge possess their degree of utility, but they can never support a comparison with the proper matter of the organs; they may serve to complete a museum, but never to form one; so we content ourselves to mention them here, in order to assign them a rank. [8] The subjects prepared by M. Azoux, are however, more proper to facilitate and extend the study of anatomy; they are far superior to dried objects. It is desirable that every amphitheatre should possess one of these subjects. Anatomical pieces which place before the eyes the organs, themselves, are then the elements, “par excellence,” for the formation of collections, which are to serve as studies of normal anatomy, of pathological anatomy, and of natural history, but, the preparation and preservation of these pieces is a new science; we ought not to be astonished at it, notwithstanding the advanced state of our anatomical knowledge, if we reflect on the difficulties of all kinds, which prejudice excited in our predecessors. It is stated, it is true, that Ruysch, had discovered the means of preserving the dead body, with _all the appearance of life, without drying, with florid complexion, and supple limbs_. But, is this really the fact? and have we not good reasons to doubt such assertions, since no collection of anatomical pieces, prepared by this process, has descended to us, and no explanation has confirmed our knowledge of them?