The term soil pipe is often used to designate cast-iron pipe of any size and for any purpose in connection with the plumbing system. The latter is the sense in which it will be referred to in the consideration of the present subject. Plate XIII.
Posterior communicating artery. In human anatomy, the left and right posterior communicating arteries are arteries at the base of the brain that form part of the circle of Willis. Each posterior communicating artery connects the three cerebral arteries of the same side. Anteriorly, it connects to the internal carotid artery (ICA) prior to the terminal bifurcation of the ICA into the anterior cerebral artery and middle cerebral artery.
1 Cerebral aneurysms mostly occur in the anterior communicating artery or circle of willis. 2  The other common site is internal carotid artery.  94% of the non-intracranial aneurysms arise below the level of renals and caused by atherosclerosis.