Is the Brain which is preserv'd in the Skull all of one Piece, or one equal Mass?
No, it is distinguish'd by the means of the Meninges into the Brain it self, and the Cerebellum or little Brain; the Brain, properly so called, takes up almost the whole Cavity of the Skull, and the Cerebellum is lodg'd altogether in the hinder-part, where it constitutes only one entire Body; whereas the former is divided into the Right and Left Parts by the Meninges, which cut it even to the bottom; whence these Foldings are call'd Falx; i. e. a Scythe or Sickle.
What is chiefly remarkable in the Substance of the Brain?
The Ventricles or Cavities which are found therein, together with the great Number of Veins, Arteries, Lymphatic Vessels, and Nerves, that carry Sense to all the Parts of the Body, and Spirits for their Motion.
An exact Historical Account of all the Holes of the Skull, and the Vessels that pass thro' them.
To attain to an exact Knowledge of all the Holes with which the inside of the Basis of the Skull is perforated, they are to be consider'd either with respect to the Nerves, or to the Sanguinary Vessels.
There are nine Pairs of Nerves that arise from the Medulla Oblongata, and go forth out of the Skull through many Holes hereafter nam'd.
The first Pair is that of the Olfactory Nerves, appropriated to the Sense of Smelling, which are divided below the Os Cribiforme, or Sieve-like Bone, into divers Threads, that passing into the Nose through many Holes with which this Bone is pierc'd, are distributed to the inner Tunick of the Nose.
The second Pair is that of the Optick or Visual Nerves, that pass into the Orbits of the Eyes, thro' certain peculiar Holes made in the Os Sphenoides, or Wedge-like Bone, immediately above the Anterior Apophysis Clinoides.