For the study of the different varieties of blade we have at our disposal first of all the specimens that have actually survived. Of these the largest number are to be seen in the Naples Museum, but a considerable number are to be found scattered over various museums. An _ex voto_ tablet found on the site of the temple of Aesculapius on the Acropolis at Athens shows a box of scalpels, among which are some interesting forms (Pl. IV). The scalpels, it will be noted, are arranged head and tail alternately. A few varieties are actually described in detail in the classical authors, and, by piecing together other references to particular instruments and drawing inferences from the various uses to which we find them put, we are able to describe a surprisingly large number of forms. The sixteenth-century writers, such as Paré, and seventeenth-century writers, such as Scultetus, illustrate with great confidence many of the cutting instruments mentioned by ancient writers, but it is easy to show that in several instances they are wrong, and, therefore, I have drawn on them as little as possible. As a basis of classification we may select the following points about the blade. The form may be straight or curved. There may be only one cutting edge or there may be two, and the point may be sharp or blunt. We shall examine combinations of these in the following order: I. Blade straight-- (A) Cutting on one side only (_a_) sharp-pointed, (_b_) blunt-pointed. (B) Cutting on two edges (_a_) sharp-pointed, (_b_) blunt-pointed. II. Blade curved-- (A) Cutting on one edge (_a_) sharp-pointed, (_b_) blunt-pointed. (B) Cutting on two edges, sharp-pointed. I. A (_a_) _Straight blade cutting on one edge, sharp-pointed._ 1. Ordinary scalpel. 2. Scalpel with tip turned back. 3. Bellied scalpel. 4. Scolopomachaerion. _Ordinary Scalpel._ The ordinary scalpel had apparently a straight, sharp-pointed blade. The word which Galen, Aetius, and Paulus Aegineta use to denote scalpel is σμίλη. Latin authors use _scalpellus_, the diminutive of _scalper_. From the etymology of these terms we can learn nothing as to the shape of the blade; they are merely general terms denoting a cutting blade of any kind--chisel, graving tool, knife, &c. The word Hippocrates uses, μάχαιρα or μαχαίριον, has a more definite meaning. It is from μάχαιρα, the old Lacedaemonian sword, a broad blade cutting on one edge, sharp-pointed, and straight or with the tip turned slightly backwards. Thus, even in Hippocratic times the scalpel was apparently much of the same shape as it is now. Good examples of the ordinary scalpel may be seen in Pl. V, figs. 1 and 2 from the British Museum. They are all of steel. A variety with the point turned back at the tip is seen in one of the scalpels in the scalpel box from the Acropolis (Pl. IV).