An Account of a Book

VII. An Account of a Book Intitled, Dissertatio Epistolaris de Glandulis conglobatis Duræ Meningis humanae, indeque ortis Lymphaticis ad Piam Meningem productis. Authore Antonio Pacchiono. Romæ 1705. 8vo. This Dissertation seems to be only a Supplement, or Appendix, to a Treatise of the Dura Mater, which our Author, that Industrious and most Inquisitive Anatomist, Pacchionus, had publish’d sometime before. In this his chief Design is to inquire into the Service, and find out the Origin of that Humor, which moistens the Brain and its Membranes in every dead Animal. He mentions three things, which kept him from engaging in this Inquiry much sooner. The first was, because the Accurate Nuchius very much blamed their freedom, who were too forward in admitting any Lymphatick Vessels in the Brain: for he freely owns, that he could never succeed in this matter, tho’ with the greatest exactness he had often attempted it. The next was, because the Great Malpighius, who was so curious and happy in discovering the Glands of the Thorax and Abdomen, did never take the least notice of any in the Dura Mater. The third Obstacle, that stood in his way, was the texture of the Membrane itself; which is so thick, and composed of Fibres so very strong, that they seem almost most to be Muscular, and probably altogether unfit for lodging any such bodies as Glands are. But at last the Knife removed all these Difficulties, and he happily succeeded in the Discovery of the following Glands, which are the Subject of this Book. Before he describes these Glandulous Bodies, he premises a short Account of the Structure of the Longitudinal and Lateral Sinus's of the Dura Mater; but adds little or nothing to what the Renowned Willis, and the Sagacious Vieussens, have already said on that Subject. In examining the Cavity of the Longitudinal Sinus, immediately under its membranous Expansions, in the Area or middle of its Corda, mention'd by Dr. Willis, (that is, the small transverse Fibres, which like Ropes keep the Walls of this Sinus from being over-dilated by the influent Blood,) our Author had the good Fortune to discover a great number of Conglobate Glands, which are all contained by a fine and proper Membrane, as in a Bag. For the most part they appear in Clusters, and are seldom scatter'd here and there. Their Figure is roundish; and in bigness they equal a Silk-worms Egg, if inspected as soon as the Body is opened; but if the Meninx be macerated in Vinegar for a Month, or more, they are bigger than a Millet Seed. In Old People, and in those who have died of a lingering Disease, they may be seen by the naked Eye, without any Microscope, or previous Preparation. They are incapsuled with fine Carnous Fibres; whence they put on a pale Colour: But when these Fibres are much relaxed, as happens in an Hydrocephalus, or Comatose Distempers of the Brain, they become white and very big. In the Lateral Sinus's they are seldom or never observ'd; because in those, he thinks, they would have been more subject to the superincumbent weight and pressure of the Brain, which would much have incumbered their Office; but by their situation in the Longitudinal Sinus, there could no such inconveniency happen. From the aforesaid Glands innumerable fine Threads arise, and are only their Excretory Vessels, which are spread all over the inside of the Pia Mater, being accompanied and strengthened in their course by Fibres and other Blood Vessels. It is these Fibres which join the Meninges to one another: And if you take care that the Dura Mater be not hurt in taking off the upper part of the Scull, in dividing these Membranes, you may observe Liquors of different colours ouze and drop from them when cut. Our Author is not positive that these Excretory Ducts penetrate into the Medullary Substance of the Brain; but affirms, that they creep along its inner Protuberances and accidental Cavities. This Discovery confirms what Bohn and some others have said about the Lymphatics of the Brain; but before our Industrious Author, none did ever so much as pretend to fix their Origination; which he has traced from the Glands lodged in the Longitudinal Sinus, as above. The Use he assigns to these Glands, is to separate and strain a particular kind of Humor from the Blood; which, in his Opinion; may serve to keep the Membranes and Surfaces of the Cavities and Protuberances of the Brain from growing too dry by their continued Motion. When this Humor becomes either deficient and wanting, or exuberant and in too great a quantity, tity, the Parts above-named are unfit for the Natural discharge of their respective Offices, whence several dangerous Distempers must necessarily follow: He adds some Cases of this kind, which he has observed in the Dissection of morbid Bodies. Advertisement. All Persons who have any thing to communicate to the Royal Society, are desired to direct it to be left at their House in Crane-Court, in Fleet-street, London. London: Printed for H. Clements at the Half Moon, and W. Innys at the Princes Arms, in St. Paul's Church-yard; and D. Brown at the Black Swan without Temple-Bar.