_Relation of the Artery, Vein and Nerve._—The femoral vein at Poupart's ligament lies close to the inner side of the artery, separated from it by a thin fibrous partition; but two inches down the vein runs behind the artery and then to its outer side. There is no nerve in relation to the artery in the upper third, the anterior crural nerve lies about half an inch to the outer side of the femoral artery, being separated from the artery by the ilio-psoas muscle. In the middle third of the thigh the internal saphenous nerve is situated on the outer side of the artery, but not usually in the same sheath with the artery. _To raise the femoral artery_ in its proper place, is to measure down from Poupart's ligament from one and one-half to two inches in the linear guide, and there begin the incision, making it two inches or less in length. This will bring the incision below the point where the collateral branches are given off. Cut through the skin, then the fat, which will vary in thickness with the subject. Underneath the fat are several layers of deep fascia, which must be split the length of the incision. The femoral artery will then be seen, and underneath it will be the femoral vein. Both will be in the same common sheath of fascia, which may be removed with a hook by gently tearing the sheath loose over the artery. When the artery has been loosened the length of the incision, raise it to the surface, placing a bone separator underneath for a bridge. If it is desired to remove the blood, the femoral vein should then be raised. CHAPTER XVII. CAVITY EMBALMING. =Cavity Embalming.=—In shipping a body, cavity embalming must always be resorted to and consists of introducing a trocar into the abdominal and thoracic cavities and injecting sufficient fluid over the contents of these cavities to thoroughly preserve them. The scientific work in the embalming of to-day is being done on the arteries, but cavity embalming should still hold an important place with those embalmers who desire to get the best results. Although the arteries have been injected, yet we find that sometimes the fluid does not reach the cavities. Any cavity may contain gas or material for decomposition, such as blood, pus, lymph, or as in perforation of the intestines, feces in the abdominal cavity. Besides these we always have the bacteria of decomposition, called saprophytes, which have thoroughly invaded the organs and tissues of the body as soon as sixteen hours after death. Then, if for any reason the fluid has not reached a certain part, fermentation, and putrefaction will immediately set in.