In these preliminary observations, many of our read ers will recognize the masterly hand of one of the most celebrated anatomists of the age. We acknowledge, with equal pride and gratitude, that they were drawn up, almost verbatim, from Dr Barclay's introductory lec tures, which, with the frank liberality that characterises a great mind, he allowed us to make use of in our work. It will be considered as no mean pledge of the value of the subsequent part of this article, that it has received his decided approbation.
We shall now conclude the history of anatomy, by a brief account of the new nomenclature with which Dr Barclay has enriched the science.
It had been long regretted, that the nomenclature of anatomy was both vague and indefinite ; and that, in particular, those terms, which referred to the position and aspect of the several parts of the body, were ambi guous. and, having been contrived merely for the human body, could not properly be employed in describing the structure of inferior animals. Thus, what is superior or iy.fiTior in man, is anterior or posterior in quadrupeds. What is external or internal, in one situation of the bo dy, is reversed in another, &c. To take a familiar instance, in the fore-arm, the side of the hand next the thumb has sometimes been described as external, some times as internal ; and sometimes, (as by Albinus,) as anterior ; just as it has been viewed in a state of 8upi nation, of pronation, or between both.
Some attempts had been made in the latter end of the last century, by Dumas and other French writers, to reform the language of anatomy, as their countrymen had lately reformed that of chemistry ; but in this we do not think they have been very successful. Their sub stitution of sus and sous for superior and inferior, does not remove the ambiguity of these expressions, and some of their compound terms are so long, that they appear more like definitions than names.
Dr Barclay published his thoughts on anatomical no menclature in 1803, after having employed many of the terms which he there introduces, in his public lectures.
The new terms recommended by Dr Barclay refer chiefly to position and aspect.
One of the most general aspects of the parts of an animal body is that which looks towards an imaginary plane, supposed to be drawn through the head, neck, and trunk, dividing the whole body into two equal and similar halves. This is called by Dr Barclay, the menial
plane ; those parts which look towards this plane are said to have a mesial aspect ; while those which look towards the opposite direction have a lateral aspect, this aspect being dextral or sinistral, according as the part lies to the right or kft of the menial plane Instead of external, used to denote those parts which are next the surface, Dr Barclay employs the term der mal, and for internal, which signifies parts at a distance from the surface, he uses central ; and sometimes, in speaking of the circumference of an organ, he calls those parts which are next the circumference, peri pheral." The particular aspects and positions have different names, according as they „refer to the the trunk , or the extremities.
The head, besides the general aspects of meNial, dextral, sinistral, peripheral, and central, has four or hive particular aspects. Thus, the parts next the top of the head are coronal; those next the base, basilar; those next the occipital protuberance at the back of the head, (called by the Greeks Inion,) arc finial; those opposite to this, at the root of the nose, glabalar ; while those parts which arc at the greatest rectilineal distance from the inion, (as the chin in man,) are antinial. If lines be drawn between every two of these opposite aspects, and be tween those of dextral and sinistral ; we shall have four diameters for the head, denominated from the aspects at the extremities of the line inantinial, and In the trunk that aspect of organs which is next the atlas, or first joint of the neck, is atlantal ; that of those next the sacrum is sacral ; those which look to the sternum or breast-bone, have a sternal, and those which look towards the opposite part or back have a dorsal aspect.
In the extremities, beside the usual general aspects, there are two terms that refer to both kinds of extre mities. That part of any of their component bones, which is next the trunk, is called proximal, while that which is in the opposite direction is said to be distal. The extremities themselves are of course atlantal and sacral, according as they are next the atlas or the sa crum.