its Insertions into the Cortical, and the Medulla Oblongata, and examined the Rises of all the Nerves, and went along with them into every Part of the Body with wonderful Curiosity. Hereby not only the Brain was demonstrably proved to be the Fountain of Sense and Motion, but also by the Courses of the Nerves, the Manner how every Part of the Body conspires with any others to procure any one particular Motion, was clearly shewn; and thereby it was made plain even to Sense, that where-ever many parts joined at once to cause the same Motion, that Motion is caused by Nerves that go into every one of those Parts, which are all struck together. And though Vieussens and du Verney have in many things corrected Dr. Willis's Anatomy of the Nerves; yet they have strengthened his general Hypothesis, even at the Time when they discovered his Mistakes, which is the same thing to our present purpose. Galen, indeed (a),(a) De V. P. l. 8. c. 4. had a right Notion of this matter, but he traced only the larger Pairs of Nerves, such as could not escape a good Anatomist.
But the manner of the forming of the Animal Spirit in the Brain was wholly unknown. In Order to the Discovery whereof, Malpighius (b)(b) De Cerebri Cortice. by his Microscopes found that the Cortical Part ofthe