A few instruments bear the image of deities connected with medicine, or attributes of these. The figures of Aesculapius and his daughter Hygeia are found on medicament boxes, the former with the serpent entwining his staff, the latter feeding a serpent from a bowl. The serpent is sometimes found on a probe. A uterine dilator from Pompeii also carries it. A probe surmounted by a double serpent (caduceus form) was found in the Roman Hospital at Baden. Two scalpels in the Naples Museum carry on their ends the head of Minerva Medica. The quadrivalve speculum in the Naples Museum has each end of the crossbar tipped with a fine image of a ram's head. There is also a medicine shovel with the same symbol. Illustrations of these instruments will be found later. _Preservation._ Some of the instruments of silver retain their brightness as when they were made, but under certain circumstances a considerable amount of oxidation takes place, and then they have a thick black coating. Very few bronze articles are found to have retained their colour. In volcanic districts the various sulphur compounds formed give rise to a beautiful patina of varying shades of green and blue, sometimes so evenly distributed as to resemble enamel. This, when fine, much enhances the value of the article. Articles of iron are sometimes but little destroyed. It is surprising in how good condition the iron or steel may be. The bow of a shears is sometimes quite springy. In some cases a steel or iron article is often represented by a mass of oxide bearing some resemblance to the original. In others only a shapeless mass of oxide remains. _Finds of Instruments._ Finds of ancient surgical instruments, though not by any means common, are still sufficiently numerous for specimens to have found their way into most of our larger museums; and private collectors have here and there acquired considerable numbers. The most prolific source has been the excavations at Herculaneum and Pompeii, which have now been systematically pursued for nearly three hundred years, while the objects found have been deposited in the National Museum at Naples. In 1818 a physician's house with a large number of surgical instruments was discovered in the Strada del Consulate of Pompeii, and two chemists' shops have also been found with instruments in them. Besides these there is a large number of instruments from other finds in the two buried cities.