to be somewhat unusual that he constantly makes it to consist of the third part of the Flank because it doth not seem to be necessary to erect a larger Orillon in a greater Fortification than in a lesser I am apt to believe that it is sufficient to allow it so much strength as to be able to resist the force of the Cannon Afterwards he causeth the two other parts of the Flank to return within the body of the Bastion assigning them the Figure of the sixth part of a Circle and this is what hath been lately termed the hollow Tower or Flank retired Lastly for the better covering of the Flanks he placeth the wings of the Works which he builds before the Curtain within the Faces at the distance of some Fathoms from the Orillon It hath been believed for a long time that double Flanks were of very great use in the defence of a place but they are wholly omitted by Monsieur de Vauban tho' his reasons are not as yet well known neither doth he regard False-Brayes which is not to be admir'd and to defend the Trench he makes use of a small and low Tenail to very good purpose which he placeth before the Curtain and is separated from it by a little ditch The Faces of this Work are in the same delineation with those of the Bastions The Flanks are distant from the others from 10 to 12 Fathoms and Monsieur de Cambray declares that this proves what he had before asserted concerning the Line of Defence for he had avouched in one of his Maxims that it ought not to exceed 125 Fathoms nevertheless it appears from his Tables that it contains from 126 to 138 Fathoms There needs not much pains to be taken with respect to the Angle of the Bastion only assigning to it from 60 to 100 degrees that it may be able to sustain it self and that the Bastion may be of a sufficient largeness But as for the Faces they seem to require more care to make them of an equal strength since they do not exceed at most above 50 fathoms Lastly touching the Trench the Author follows the opinion of Monsieur de Clermont who allots from 18 to twenty fathoms for its breadth and from 18 to 20 feet for its depth The Glacis's are made as large as they can be conveniently not allowing less to them than 36 fathoms but as for the Rampart its breadth is limited to 10 fathoms and Monsieur de Vauban derides their project that would have it proportioned to the largeness of the Polygons as if little places were not attacked with the same Arms as those that are greater In the fifth and last Book the Author shews (bb) 89. the structure of divers Fortresses erected in the Field and afterwards lays down (cc) 95. Rules for the fortifying of an irregular place But as to the method used by him it may be affirmed that he departs a little from his own Maxims and more especially from the first in regard that the Trench the Base of the Rampart c. are diminished proportionably as the side of the Polygon exceeds 180 fathoms unless one would say that in Triangles which are unequal there is the same proportion between their sides This Book is concluded with mentioning somewhat concerning Artillery whilst a larger discourse thereof is reserved to a Treatise wherein the Author promises expresly to inform us of the manner of attacking a place according to the judgment of Monsieur de Vauban the publication of which is impatiently expected X. OSTEOLOGIA NOVA Or A New Treatise of the Bones and the Parts belonging to them with the Manner of their Growth and Nutrition Communicated to the Royal Society in several Discourses By Clopton Havers M. D. Fellow of the Royal Society London for S. Smith 1691. Pag. 310. IT would require a Discourse as large as any of the Five Dissertations of Dr. Haver's Book should we go about to set down every Thing that is new and curious therein And therefore the extraordinary Abundance of Matter will enforce us to pass over many remarkable Things upon which we should have insisted much longer but that they are as we may say so heap'd up in Piles one upon another I. The First Discourse treats of the Nature of Bones and describes the Membrane which covers them their interiour Frame and Figure The Author begins with a kind of Prologue very significant to the purpose by giving an Idea of the manner of Generation according to the Principles of de Graef and Monsieur Drelincourt He supposes (a) p. 7. That all the Parts of the Creature are delineated in the Female's Egg while it is yet in the Womb and before the Seed of the Male has given it Life That the most volatile Parts of the Seed insinuating themselves into the Umbilical Vein of the Egg through the Pores of the Membrane of the Ovary that Vein carries those Particles to the two Ventricles of the Heart where they raise a Fermentation in the Humors which there they meet withal that rarifies and dilates them and putting the Fibres of the Heart upon a Contraction produces that Beating which is the Sign and Beginning of Life Part of these rarify'd Humors falling from the right and left Ventricles into the Aorta imparts its Motion to the Matter contained in it and in all the Vessels which depend upon it The Arteries being thus extended and the Liquor within them being agitated opens its self a Passage through the Veins and this compleats the Circulation These Humors thus circulating meet with Glandules in their way upon the sides and at the Extremities of the Arteries through which there is a necessity for them to pass These Glandules being a sort of Strainers the most subtle Parts and those which first get through the Glandules of the Brain are those which are call'd the Vital and Animal Spirits of which when there are sufficient to give motion to the Original of the Nerves then apparently it is that the Soul is infus'd into the Foâ—tus The Membrane (b) p. 14. which covers the Bone is very thin and exquisitely sensible and made up of most minute and curious Threds which deduce their Original from the Dura Mater and from several Muscles and Tendons Those that descend from the Dura Mater lie the nearest to the Bones and are all parallel but those which proceed from the Muscles take a different course according to the situation of the Muscle from whence they proceed This Membrane is fastned to the Bone by the nature of their Substance which is viscous and slimy and by certain little Fibres of that Membrane which enter into the Pores of the Bone It is appointed for Five several Offices 1. It serves to cover the Bones 2. It conveys Spirits into their Substance which preserve their Heat render them sensible and assist them in their growth and nourishment 3. It contributes to limit the growth of the Bones 4. It serves
to keep them joyn'd and knit together and with the Tendons of the Muscles 5. This Membrane being extreamly sensible causes us to feel the least Disorder that happens in the structure of the Bones and directs us in the Application of outward Remedies to the Place affected The Bones (c) p. 30. at their first beginning are no more than a clammy Gelly which drying by little and little becomes a Gristle * Cartilage and afterwards a perfect Bone by the evaporation of the liquid Matter and the additions of the nutritive Juice The Particles that compose them are long in shape and of a terrestrial and salt Nature but the terrestrial Particles make above two Thirds of the Mass Their Fibres are long contigâ—ous and parallel one to the other in such a manner that they form little Lamels which meeting at the Extremity of the Bones lie one over another and close up the Concavity (d) p. 43. There are two sorts of Pores in the Bones besides those which serve for a passage to the Sanguinary Vessels of which some are oblique and pierce through the Lamels of the Bones extending themselves from the superficies of the Bone to the Hollowness the other are streight and narrow and appear all along the Lamels from one end of the Bone to the other (e) p 49. The Superficies of the Bone is very uneven unless it be at the Joints where there is a necessity it should be smoother to facilitate the motion of the Parts This unevenness proceeds from the superficial Cavities and Pores which there meet together These superficial Cavities are of two sorts Some are long and like a sort of Furrows others are shorter and of a different shape The Use of both is to dilate the Surface of the Bone and to keep the Membrane more firmly fastned to it (f) p â—6 As for the Pores their Use is to serve as passages for Blood Vessels some belonging to those Vessels which convey that Blood which supplies the nutritious Juice others to them which serve to the Marrow Those of the nutritious Veins are very numerous but so small that it is a difficult thing to discern them Those of the Medullary Arteries are more remarkable and enter the Bone obliquely so that the way which they make is often Ten or Twelve times longer than the Thickness of the Bone (g) p. 61. There are two sorts of Hollownesses in the Bone and of those which are large there is but one in every Bone the rest are very numerous and resemble little Cells which render that part of the Bone spungy where they are to be found The Author gives the Reasons of all this Structure of Nature You will also find there very curious Observations upon the Teeth (h) p. 78. Dr. Havers observes That they are made up of two very different Parts The one is of the Nature of Stones having the solidity and glittering of the hardest Flints but with this difference that they will be dissolv'd by Aqua Fortis which Flints will not This Stony Matter is a sort of Rind which covers all the Part without the Gums That Part which is within the Gums is cover'd with a particular Membrane which nevertheless proceeds not from that of the Jaw-bone though this Membrane extends it self to the Fastning or Inclosure of the Teeth in the Gums and be contiguous to their Membrane II. The Second Discourse (i) p 89. treats at first of Growth and Nourishment in general which the Author afterwards particularly applies to the Bones He reduces all that Matter to Three Questions The First How the Nutritive Juice is form'd and fix'd to the Parts of young Creatures after such a sort as to enlarge their Dimensions Certain it is that that same Juice proceeds from our Nourishment chang'd into Chyle which passing through the Milky Veins to mix it self with the Blood meets with some Particles of the Nutritive Juice of the Kerness convey'd by the Lymphatick Chanels that serve for a Ferment to those of the Chyle This Milky Liquor entring the Heart and being mix'd with the Blood is there subtiliz'd and passes afterwards into the Arteries on the sides of which it meets with Kernels the Pores of which are so fram'd as only to admit the Nutritive Juice Now while the rest of the Blood pursues its Course in the Artery the Nutritive Particles are press'd out of the Kernels and advance forward through every up-lifting of the Artery and by the pressure of other little Bodies of the same nature which supply their Places till they are push'd forward into the Intervals of the Fibres where they meet with the Spirits in Motion These Spirits have a double Motion for they turn about their Centre like a Bowl thrown out of hand while according to their local Motion they describe a Line as streight as is possible Now in regard the Nutritive Parts are liquid and viscous and that the Spirits cannot impart their direct Motion to them they force them to the sides of the Vessels where they stick more especially if they meet with any hollowness or any void space Add to this that while the Creature is yet very young the Parts are very tender and the Fibres more supple and less extended So that it is no wonder if little viscous Bodies being forced in between the Extremities of the Particles of those Fibres these soft Parts give way and so separate one from the other for the infixation of new Matter The Second Question (k) p. 126. proposes What is the Cause that stops the growth of any Creature To which the Answer is That it is the hardness of the Filaments and Lamels and the firm unition of the Particles of the Fleshy and Nervous Fibres which when a Creature is come to such an Age resist the Efforts of the Spirits and Nutritive Particles so that not being able to lodge themselves in the Pores or Intervals of the Fibres which are already full they are carried off by the direct motion of the Spirits to other Kernels which rarifie them to a greater degree and employ them to other Uses The Third Question (l) p. 133. is about Nourishment the Nature of it and how it is perform'd Dr. Havers believes it to be no more than a continual Supply of the fluid and nutritious Particles that keep the Fibres the Pores the Hollownesses and in a word all the Pipes and Vessels of the Body full and in a good condition Sometimes it happens that there may be a loss of some part of the Fibres and that the void space is fill'd up by the Nutritive Juice which the circular Motion of the Spirits forces forward toward the sides of the Arteries But this the Author says is not the manner of Nature's repairing the ordinary Decays and Wasts of our Bodies For Proof of which he supposes as another Learned Anatomist * D. Tyson does that the whole Body of Man is porous and full
of Vessels which several sorts of Humors keep dilated and well sill'd so that Leanness and the Marasm it self do not proceed from that the fix'd Parts of our Body as the Flesh and Bones are depriv'd of their Substance which can never happen but by the violence of Corrosives which would cause an incredible pain nevertheless they feel no pain who are troubled with those languishing Diseases And therefore such an Atrophy must proceed from hence that the Humors which fill the Vessels and preserve them plump evaporating the Vessels shrunk and by that means impair the Dimension of the Parts The Author afterwards (m) p 143. makes the Application of his Principles to explain the manner and the limits of the growth of the Bones and how they are nourished which it is no difficult thing to do if the Reader forget not what has been already observ'd That both in the Foetus and a new born Child the Bones are made up of a Matter which is very tender and easiâ—y gives way but as it grows changes into Gâ—istles that the Particles which compose the Gristles do not form continued Threads but leave between them Cavities or void Spaces which in time are fill'd up with Nutritive Juice That it slides along a good while before all the Spaces of those Particles are fill'd up and that the Gristles are converted into perfect Bones and then it is that Growth ceases the Nutritious Particles no longer knowing where to lodge themselves According to this Hypothesis Dr. Havers explains the Reason why the Bones grow crooked in the Rickets and why both that Distemper and the Neapolitan Disease many times produce Knots or Excrescencies upon the Bone III. The Third Discourse treats of the Marrow (n) p. 161 All the World knows that the Marrow is an Oyly Substance which fills the Cavity of the Bones but you shall hardly any where else meet with so exact a Description of it as the Author gives here This Marrow is enclosed in small round Vesicles of which two or three or more are contain'd in Bags of different shape and these Bags in a transparent and very slender Membrane consisting of Fibres prolong'd from the Blood-Vessels which afford it Nourishment through the Pores of the Bones These Vesicles and little Bags are also furnished with Pores through which the Marrow 's Oyl passes from one to the other and communicates it self to the Joints So that these Vesicles are also a kind of Kernels and separate the Marrow from the other Parts of the Blood (o) p. 171. When these Vesicles are full they contract themselves as all puffed up Bladders do and then discharging their Oil the one into the other it passes from Vesicle to Vesicle and from Bag to Bag till it enters into the thwarting Pores of the Bones whence it sheds it self into the streight Pores and at the Articulations and is employed into the Cavities between their Joints which it keeps moist and slippery In the great Cavities of the Bones the Marrow appears whitish speckled with Red but absolutely Red in the lesser Cells which only proceeds from the different quantity of Veins and Arteries that nourish it Some parts of this Marrow are apt to congeal because they are mix'd with Nitre Though the Marrow (p) p. 178. contributes nothing to the Nourishment of the Bones that are furnished with Blood-Vessels appointed for that purpose it is otherwise many ways useful For 1. It moistens the Substance of the Bones and by its oyly Nature it preserves them in good condition and hinders them from shivering 2. With the Mucilage it makes the Joints of the Bones slippery and consequently sit for Motion 3. Mixt with the clammy Mucilage it cools them and prevents their contracting a more than ordinary Heat by their Motion 4. It prevents them from wearing out wasting and bruising by rubbing one against another 5. It is after the same manner serviceable to the Ligaments which tie the Bones together preserving them from being dry and stiff and keeping them supple and slippery IV. The Fourth Discourse treats of the Mucilage and the mucilaginous Kernels (q) p. 187. These Kernels are one of the principal Discoveries of the Author who tells us they were never discerned by any person before himself They are of two sorts the one sort which is very small and numerous take up the whole Membrane of the Joint unless in that part where you meet with the second sort of these Kernels which are conglomerate bigger and consequently more remarkable than the first They are made up of several Kernels or small Membranes extended one upon another long and large at the bottom and ending usually in a point though there are some that are flat and of other different Figures They are soft and supple and not brittle so that they yield to and suffer the impression of the Bones without receiving any harm The Blood-Vessels with which they communicate are not streight but oblique so that the Blood circulating round about them the mucilaginous Particles have time to separate when they enter the Kernels The Mucilage (r) p 201. which distills out of these Kernels is a clear and clammy Liquor almost like the White of an Egg. It is composed of Watry Salt and Terrestrial Parts but the Salt and the Earthy Parts make no more than about the 32d part of the Mixture It partakes of the nature of the Serum only that it is not to be all turn'd into a Coagulum by the heat of the Fire as the Serum is It serves for the same Use as the Marrow and they assist one another to perform their Functions The Mucilage renders the Marrow 's Oyl more slippery and that Oyl hinders the Mucilage from growing too thick It is formed as the Author says in the Spleen which is of a Viscous and Kernelly Substance and which has two forts of Pores the one proper for the distilling of Acids through them and the other is a Stiptick Juice which serves as a Ferment for the Blood to produce the Mucilage there Dr. Havers sets down several Experiments (s) p. 217. which he has made upon this Liquor of which the most considerable in relation to Physick are That violent Acids as Salt and Oyl of Vitriol Aqua fortis and Spirit of Nitre and Vinegar coagulate the Mucilage chiefly when it is hot so that it will become thin and fluid and that you may separate from it a kind of Whey or Serum The Author tried whether by the help of Powder of Coral Antimony Diaphorerick or Crabs-Eyes he could make it resume its first Nature but he could not bring it to pass Yet with Spirit of Sal Armon and Salt of Tartar all the Coagulation would be dissolved The Parts where these Kernels are seated are subject to Catarrhâ— because these Kernels not only separate the Mucilage from the Blood but many times also other Morbisick Humors which Nature desires to be rid of When those