pressed for the distribution of the Chyle but it diminishes the Cavity of the Breast when it resumes its natural Situation and presses the Lungs for the Expulsion of the Air in Expiration SECT III. Of the Pleura Mediastinum and Thymus Of the Pleura THE Pleura is a double Membrane which covers all the Cavity of the Thorax it arises from the Vertebrae of the Back ascends on each side upon the Ribs to the middle of the Sternum It is fixed to the Periostium of the Ribs to the internal intercostal Muscles and it covers the Midriff It s side towards the Cavity is smooth and equal but that which is fixed to the Ribs is rough The Vessels which run betwixt its Duplicature are Veins from Vena Azygos and upper intercostal Vein Arteries from the Inferior and Superior intercostal Arteries and Nerves from the twelfth Pair of the Back from the intercostal Pair and from the eighth Pair Of the Mediastinum The Mediastinum is a double Membrane formed by the continuation of the Pleura it comes from the Sternum and goes straight down thorow the middle of the Thorax to the Vertebrae dividing the Cavity in two It contains in its doubling the Heart in its Pericardium the Vena Cava the Oesophagus and the Stomachick Nerves The Membranes of the Mediastinum are finer and thinner than the Pleura and they have a little Fat The Mediastinum receives branches of Veins and Arteries from the Mammillary and Diaphragmatick and one Proper called Mediastina its Nerves come from the Stomachick it has also some Lymphaticks which open in the Thoracick Duct The Mediastinum divides the Thorax in two Parts to the end that one Lobe of the Lungs may officiate if the other be hindered by a Wound on the other side of the Thorax it fixes the Heart in its Pericardium and preserves them from external Injuries Sometimes there is a matter contained betwixt its Membranes immediately under the Sternum which may occasion the Trepaning of this place Of the Thymus The Thymus passes for a Conglomerate Gland a little softer than the Pancreas situated in the upper Part of the Thorax under the Claviculae where the Cava and Aorta divide into the Subclavian branches This Gland is big in Infants but as they grow in Age it grows less It receives Veins and Arteries from the Jugulars Nerves from the Par Vagum and Lymphatick Vessels which discharge themselves in the Subclavian Vein The use that is commonly given to the Thymus is to be a little Cushion to support the Thoracick Duct and to strengthen the Cava and Aorta at their Divisions in the Subclavian Vessels to defend them against the hardness of the Vertebrae But 't is probable that its principal use is to filtrate or separate some Liquor which is not yet known SECT IV. Of the Pericardium Heart and its Parts Of the Pericardium THE Pericardium is a thick Membrane of a Conick Figure it resâ—mbles a Purse and contains the Heart in its Cavity It s Basis is pierced in five places for the Passage of the Vessels which enter and come out of the heart it is fixed to the Mediastinum and to the Midriff It receives its Vessels from the Axillaries and Phrenicae Nerves from the recurrent and Diaphragmatick It has Lymphaticks which discharge themselves in the Thoracick Duck. It defends the Heart from external Injuries Of the Water contained in the Pericardium In the bottom of the Pericardium there is a clear and sweet tasted Water but in some tinctured a little with Blood It is found in abundance in the Pericardium of Women and Old Men but there is little of it in those that are Hectick and Pleuritick When it is in too great quantity it causes a Palpitation of the Heart and sometimes Death Authors do not agree about the rise of this Water Some say that it comes from the Extremities of the Arteries others that it comes thorow the Substance of the Heart but it 's more probable that it is filtrated thorow the Glands which are at the basis of the heart and that it may not abound too much nor putrify by standing too long it is taken up by some small Glands which are in the Membrane of the Pericardium and from them carried by the Lymphaticks into the Thoracick Duct Of the Situation Figure and Connexion of the Heart The Heart is situated in the middle of the Thorax between the two Lobes of the Lungs it is of a Conick Figure It s basis is the upper end and its Apex or Point is the lower end which is turned a little to the left side therefore its motion is best felt there It is tied to the Mediastinum to the Pericardium and sustained by the great Vessels which bring and carry back the Blood It is covered by a Membrane which is the proper Membrane of the Muscles its basis is always surrounded with Fat in which there are some small Glands Of its Vessels It has two Veins which come from the Cava immediately before it opens in the Heart and they are accompanied with two Arteries from the Aorta which run thorow all the Substance of the Heart they are called the Coronal Vessels The Veins on the right side communicate at their Extremity with the Veins of the left In like manner do the Arteries of each side communicate with one another and it is the same almost in all the Parts of the Body The Heart receives a multitude of small Nerves from the eighth Pair particularly they creep in great numbers about the Aorta and on the left Ventricle It has also some Lymphaticks which discharge themselves in the Thoracick Duct At the basis of the Heart there are two Auriculae or little Ears Of the Auriculae one on the right the other on the left side In the right Ear opens the Vena Cava in the left the Vena Pulmonaria The first discharges the Blood that it receives from the Cava into the right Ventricle and the second thrusts the Blood that comes from the Vena Pulmonaria into the left Ventricle Their Figure is like the triangle Ambligonium the left is less but thicker than the right Their Substance is composed of two Orders of muscular Fibres which terminate in the tendon in the basis of the Heart and at the right Ear there is a circle like to a tendon where the Cava ends Their external Surface is smooth their internal is unequal full of small fleshy Pillars which send out small Fibres that cross and go thwart one another and betwixt these Pillars there are as many furrows which are more in the left than in the right Ear they receive Nerves from the branches of the eighth Pair They have the same motions of Systole and Diastole as the Heart which we shall explain afterwards Their Vse Their Use is to receive the Blood which is brought by the Veins and by them to be thrust
into the Ventricles of the Heart Of the Ventricles of the Heart In the Heart there are two Cavities or Ventricles which answer to the two Ears one on each side the sides of these Cavities are very unequal full of Fibres and little fleshy Productions long and round of a different Figure and bigness called Columnae or Pillars Betwixt these Fibres there are several furrows in the sides of the Ventricles especially in the left Ventricle they are deeper and larger they contribute much to the close contraction of the Ventricles And because the side of the right Ventricle is much thinner than the left therefore there are often two or three fleshy Fibres which come from the middle Partition to its opposite side to hinder it from dilating too much The right Ventricle seemeth wider than the left which is longer and narrower than the right and its sides stronger and thicker The two Ventricles are separated by the Septum Medium which is properly the inside of the left Ventricle being its Fibres are continued with the Fibres of the opposite side of the same Ventricle The Vessels which enter and come out of the Heart are the Vena Cava the Arteria and Vena Pulmonaria and the Aorta or Arteria Magna Of the right Ventricle and of its Valves The right Ventricle receives the Blood from the Vena Cava thorow the right Ear and at the mouth of the Ventricle there are placed three Valves made of a thin Membrane they are of a triangular Figure and are called Tricuspides their bases are fixed to the mouth of the Ventricle and their Points tied by small Fibres to the fleshy Productions so that when the Heart contracts its Point approaches its basis the fleshy Productions move upwards therefore the Fibres of these Valves are relaxed and the Valves lifted up by the Blood which gets underneath them because the furrows and fleshy Productions keeping the Valves at a little distance from the sides of the Ventricle give way to the Blood to pass under them and so to thrust up the Valves which shut so closely the entry into the Ventricle that the Blood cannot return the way it came in But when the Ventricle is dilated the Fibres are pulled down and the Passage made open for the Blood to enter Of the Valves of the Arteria Pulmonaria When the Heart contracts the Valves being lifted up the Blood in the right Ventricle finds an open Passage into the Arteria Pulmonaria which rises immediately out of the right Ventricle its Mouth is less than the Cava it has three Valves called Segmoidales or Semi-lunares because they resemble a Half-Moon or Segment of a circle their Substance is membranous When they separate they give passage to the Blood from the Ventricle into the Artery but they shut the Passage and are thrust together by the Blood if it endeavours to return Of the Valves of the left Ventricle The Vena Pulmonaria discharges it self thorow the left Ear into the Ventricle of the same side At the Orifice of this Ventricle there are two Valves called Mitrales because when they are joined together they resemble a Mitre they are broader than the other Valves they are situated and have the same use as the Tricuspides in the right Ventricle Of the Valves of the Aorta The Aorta or great Artery rises immediately out of the left Ventricle it has three Valves which have the same Use and Figure as the Semi-lunares in the Arteria Pulmonaria Of the Substance of the Heart and of the order of its Fibres The Heart is a compound Muscle its Substance is made of Fibres of the same Nature as those of other Muscles there are several Orders of them which have different Directions and all their Tendons are in the basis of the Heart The First or External Order is of Fibres which surround the whole Heart they go in an Oblique or Spiral Line from the left to the right except on the Surface of the right side some of its finest Fibres go in a straight Line from the basis to the Point The Second or next order surrounds also the whole heart they have a contrary Direction which is from the right to the left in an Oblique or Spiral Line The next Orders are only proper to the left Ventricle The first which is on the external side of the Ventricle goes in an Oblique Line from the left to the right The second Order is on the inside or that which makes the Septum Medium or Partition Wall of the Ventricles they go in an Oblique Line from the right to the left and they are continued with the foregoing Fibres at the Point of the Heart All these Orders of Fibres come together as to one common Centre at the Point of the Heart But Obs That all the Fibres of the same Order do not always go from the basis to the Point for some after they have gone about half way obliquely from the one side turn up obliquely and are inserted in the basis on the other side Neither do all the Fibres in the same order keep together for some intermix with the Fibres of the next Order so in separating these Orders many Fibres are broken Some of the Fibres in the internal Orders proper to the left Ventricle terminate in the fleshy Productions of the same Ventricle The Bone which is found in the basis of the Hearts of several Beasts is nothing but the tendons of the Fibres of the Heart ossifyed it is sometimes found in Men. Of the Systole and Diastole of the Heart This Muscle has two Motions which they call Systole and Diastole The Systole is when the Fibres of the Heart contract its Point approaches its basis the Heart becomes short its sides swell and its Cavities are strongly pressed on all sides The Diastole is when this Muscle ceaseth to act its Fibres are lengthened its Point retires from its basis its sides fall and its Cavities become large and wide Of the Circulation of the Blood thorow the Heart Having described the Heart and its Parts let us now consider the Circulation of the Blood which is performed by means of this Muscle the Vena Cava Ascendens and Descendens unite in one and open into the right Ear where they unite there is a little Protuberance made by their Coats on the inside of the Canal like an Isthmus which directs the Blood both of the one and the other into the Ear and so hinders them from rushing upon one another The right Ear in its Diastole receives the Blood from the Vena Cava which by its Systole is thrust into the right Ventricle for the tendinous Circle which is at the Mouth of the Cava contracts and hinders the Blood to return into it which at the same time is in its Diastole in the Systole of the right Ventricle the Blood is thrust into the Arteria Pulmonaria for it cannot return into the Ear
because of the Valvulae Tricuspides which communicates with the Vena Pulmonaria which carries back the Blood into the left Ear which in its Systole thrusts the Blood into the left Ventricle which is then in its Diastole In the Systole of this Ventricle the Blood is thrust into the Aorta for it cannot return into the Ear because of the Valunlae Mitrales which carries it thorow all the Body Now the Aorta when it comes out of the Heart ascends a little upwards and then turns downwards to form the descending Trunk because the Blood might offend the Brain if it ran with that impetuosity with which it 's thrown out of the Heart and from the upper side of this turning the Cervical and Axillary Vessels do arise by this artifice the Blood collides against the sides of the Aorta its force is broken part of it is taken in by the Mouths of the ascending branches but it s greatest part is directed downwards Of the Circulation of the Blood in the Foetus Let us now consider which way the Blood circulates in the Foetus for this you must observe that in the right Ear on the lower side of the Protuberance of the Cava just opposite to the Mouth of the Cava Descendens there is a hole called the Foramen Ovale which opens into the Vena Pulmonaria this hole has a Valve which suffers the Blood to enter the Vein but hinders it to come back again There is likewise a Passage or Canal called Ductus Bottali which comes from the Trunk of the Arteria Pulmonaria and goes to the Trunk of the Aorta Now the Blood which comes from the Placenta by the Umbilical Vein into the Porta is sent into the Cava by a Canal which goes straight from the Trunk of the Porta to the Trunk of the Cava in the Liver This ascends the Vena Cava and is directly thrown thorow the Foramen Ovale into the Vena Pulmonaria which carries it into the left Ventricle which throws it into the Aorta to be distributed thorow all the Body But the Blood which comes down the Vena Cava ascendens is diverted by the Isthmus of the Cava from the Foramen Ovale and falls into the right Ventricle which thrusts it into the Arteria Pulmonaria from whence it 's immediately carried by the Ductus Bottali into the Aorta to be mixt with the rest of the Blood By this you see that the Blood which comes from the Vena Cava descendens passes only thorow the left Ventricle whilst the Blood which comes from the Cava ascendens passes only thorow the right Ventricle Thus having shewed what way and by what means the Blood circulates thorow the Heart let us now reflect a little upon the quickness of its motion Each Ventricle will at least contain an Ounce of Blood and therefore we may safely suppose that the Heart throws into the Aorta an Ounce of Blood every time it contracts The Heart contracts 4000 times in one Hour or sometimes more and sometimes less according to the different Temperaments Sexes and Ages from which it follows that there passes thorow the Heart every hour 4000 Ounces or 350 Pound of Blood Now the whole mass of Blood is but about 25 Pound so that a quantity of Blood equal to the whole mass of Blood passes thorow the Heart 14 times in one hour which is about once every 4 minutes I say a quantity which is equal to the whole mass of Blood and not the whole mass it self for it is not to be supposed that the Blood which goes to the Extremities can return to the Heart as soon as the Blood which goes only to the Kidneys or Liver The Velocity and quantity of Blood together with the time it takes to run in different Blood Vessels differ according to the different lengths and orifices of the Vessels according to the greater and lesser Compression the Vessels receive in the different Parts thorow which they run according to different quantity of Secretions from the Vessels in the several Parts of the Body according as the Vessels have more or less turnings and windings and according as they divide into more of fewer branches These things determinate the Velocity Time and Quantity of Blood in the several Vessels of the Body In the Blood there is much volatile Salt and Spirits some Phlegm and Sulphur a little Earth but little or no fixt Salt Alcali's dissolve it and Acids coagulate it SECT V. Of the Lungs Of the Figure of the Lungs THE Lungs are in the middle of the Cavity of the Thorax they are divided into two Lobes by the Mediastinum and the left is ordinarily subdivided into two more The Figure of both Lobes together resemble a Cows foot being a little concave betwixt the two Lobes where they embrace the Heart and behind where they lie upon the Vertebrae but before where they touch the Sternum and Ribs they are Convex The colour of the Lungs in a Foetus is of a pale red but after that the Air has once entered them Of their Colour and Connexion they lose their red and remain always pale yet in Adults they are variegated with the one and the other They are tied to the Sternum by the Mediastinum before to the Vertebrae by the Pleura behind where it rises from the Vertebrae to the Heart by the Vena and Arteria Pulmonaria and sometimes to the Pleura where it covers the Ribs particularly in the left side and especially after a Pleurisie Of the Membranes of the Lungs The Lobes of the Lungs are covered with a double Membrane the External is smooth fine but close The Internal is rough and unequal formed by the Extremities of the Vessels and Membrance which tie the Vesicles together It resembles the side of a Honey-Comb Of the Structure of the Lungs Each Lobe is subdivided into an infinite number of little Lobes disposed like so many Grapes upon the Sides and Extremities of the branches of the Bronchiae covered each with their proper Membrane and tied together by a number of Membranes which fill up the Spaces that these Lobes leave between one another Each little Lobe contains an infinite number of small and little Orbicular Vesicles which leave small Interstices between them which are full of small Membranes like those which tie the Lobes together Each Vesicle receives a twig from the branch of the Brochiae that enters the Lobe in which they are contained This twig opens in their Cavity which is divided into little Cells which communicate with one another and a twig from the Vein Nerve and Artery which are spread upon the Membranes of the Vesicle each Vesicle communicates with one another Of the Vessels of the Lungs Now the Vessels which enter the Lungs are the Trachea or Aspera Arteria which comes from the Larynx the Arteria Pulmonaria which comes from the right Ventricle and Vena Pulmonaria which comes from the left Ear
of it comes out at the hole in the foreside of the same Bone under the Orbit and is distributed in the Cheeks and Nose Another passes under the Processus Zygomaticus and is distributed in the temporal Muscle and the third is distributed in the Palate and Muscles of the Pharynx The third branch of the fifth Pair passes thorow another hole of the Os Sphaenoides and then it divides into two branches the first of which is again divided into four branches of which the first passes between the Condile and the Corone of the lower Jaw to the Massater The second is distributed in the Crotaphites The third passes under the Processus Zygomaticus to the Buccinator Glands of the Cheeks and upper Lip And the fourth passes from behind the Condile of the lower Jaw where it joins the Pars Dura over the Jaw and is distributed in the Face The second branch is divided into three others The first passes between the Pterigoidaeus Externus and the Internus and towards the Angle of the lower Jaw it sends out a branch which makes the Chorda Tympani which goes also to the Muscles of the Malleolus and then it joins the Portio Dura before it comes out of the Cranium the rest is spread on the Chin. The second goes along the sides of the Tongue sends out several branches which join the ninth Pair It gives also some twigs to the Glandulae Sublinguales to the Muscles of the Tongue and Os Hyoides The third goes to the teeth of the lower Jaw by the holes in its inside The sixth Pair The sixth Pair of Nerves rise from the sides of the Processus Annularis This is a small Nerve which passes straight thorow the Foramen Lacerum and is wholly spent on the Musculus Abducens But a little before it enters the Orbit it casts back a branch which alone makes the root of the Intercostal Nerve It passes out of the Skull by the same passage the Carotidale Artery enters As soon as it is come out of the Skull it with a branch of the tenth Pair and of the first and second of the Vertebrae of the Neck forms a large Plexus called Cervicalis Below this it receives a branch made of a twig of the tenth Pair and of the first of the Neck As it descends above the Musculus Scalenus and below the eighth Pair it receives a branch from each of the Vertebral Nerves When it comes to the Clavicula it divides into two branches of which one passes above the Axillary Artery and the other under it and then they immediately join again they with a branch of the first Pair of the Back form a pretty large Plexus at this place and sometimes before for it observes no regularity it casts out a branch which with a branch of the eighth Pair forms the Plexus Cardiacus then it goes down the Cavity of the Thorax under the Pleura near the Vertebrae and as it passes by it receives a branch from every Pair of the Back by which it grows bigger and bigger As it goes out of the Thorax it divides into several branches of which the three Superior in the right side form the Plexus Hepaticus and in the left the Plexus Splenicus These Plexus's furnish Nerves to the Kidneys to the Pancreas to the Caul to the lower Part of the Stomach to the Spleen to the Liver to the Mesentery to the Intestines and their branches form a large Net upon the Mesenterick Arteries called Plexus Mesentericus The Inferior branches as they go down upon the Vertebrae of the Loins receive a branch from the first of the Loins and they send out some branches which join those of the Superior branches which go to the Guts and which form the Net upon the Mesenterick Arteries Then they go down into the Bason and form a large Plexus above the streight Gut to which it gives Nerves as also to the Bladder Vesiculae Seminales Prostratae in Men and to the Womband Vagina in Women Nervus Auditorius The seventh Pair is the Nervus Auditorius it arises from the hind part of the Processus Annularis it enters the hole in the inner Process of the Os. Petrosum it divides into two branches that which is soft is called Portio Mollis and it is distributed in the Labyrinth Cochlea and Membranes which cover the Cavities of the Ear. That which is hard is called Portio Dura it goes out of the Ear by that hole which is between the Processus Mastoides and Styloides it divides into two branches of which one goes to the Muscles of the Tongue or Os Hyoides and it gives a small branch to the eighth Pair The other is distributed in the External Ear Nose Lips and Cheeks Par Vagum The eighth Pair is the Par Vagum it rises from the sides of the Medulla Oblongata behind the Processus Annularis by several Threads which join together and go out by the same hole that the Sinus Laterales discharge themselves into the Jugulares It is joined by a branch of the Nervus Spinalis or Accessorius Willisii and by a small branch of the Portio Dura immediately after it comes out of the Skull it gives a small branch to the Larynx as it goes down the Neck above the Intercostal Nerve by the side of the Internal Carotide At the Axillary Artery it casts back the recurrent Nerves of which the right embraces the Axillary Artery and the left the Aorta These two branches ascend on each side of the Trachea Arteria to the Larynx where they are spent on the Muscles of the Larynx and Membranes of the Trachea Then the eighth Pair after it has entered the Cavity of the Thorax sends out two branches which with the branches of the two Intercostals form a little above the Heart between the Aorta and the Trachea the Plexus Câ—â—dincus which gives a great number of small branches to the Pericardium and Heart particularly very many creep along the Aorta to the left Ventricle The eighth Pair gives also several branches to the Lungs which accompanying the Bronchiae then it descends upon the Oesophagus and is spread upon the Stomach and some twigs go to the Concave side of the Liver as has been said already With this Nerve it is usual to describe another which passes out of the Skull at the same hole with it It is called Nervus accessorius Willisii it arises from the Medulla Spinalis about the beginning of the sixth Pair of the Neck as it ascends to the Head it receives on each side a twig from the first five Pair of Nerves of the Neck as they rise from the Medulla Spinalis then it enters the Skull and passes out of it again with the eighth Pair and is wholly spent upon the Musculus Trapezius The ninth Pair The ninth Pair rises from the Processus Olivares of the Medulla Oblongata it passes out of the Skull by its own proper hole in the Os
Line This Coat is loose and stretches very easily 't is not closely tied to the rest The second is a Web of small Vessels in form of a Net it furnishes the necessary Nourishment to the rest of the Coats The third is made of little Glands which separate the serosity of the Blood brought by the Vessels of the second Coat The fourth is composed of Muscular and Spiral Fibres whose Parts successively contracting hasten the Circulation of the Blood The only reason why the Veins do not beat as the Arteries do is because the Blood in the Veins runs from a narrow Channel into a broader whereas in the Arteries it runs from a wide Vessel to a narrower one Authors do not agree about the Origination of the Veins Some say that it is in the Heart and some others will have them to rise out of the Liver Others think that they come from all the Parts of the Body by their little branches which are distributed thorow it where they say they have their beginning as so many roots which join to make a Trunk or as little Brooks that produce a River But they have juster thoughts who think that they have no Origination at all no more than all the other Parts of the Body which are all formed in the Cicatriâ—â—lâ— of the Egg where they only grow and are insensibly disclosed The branches of the Veins in proportion as they recede from their Trunks they divide into an infinity of little Capillary branches which at last are imperceptible These Capillary branches are spread thorow all the Viscera in the Membranes and thorow all the Fibres of the Muscles to receive the Blood which was brought there by the Arteries The Extremities of the Veins unite to all the Extremities of the Arteries But because there are more Capillary Veins than Arteries the Veins unite with one another and so likewise do the Arteries that if one Branch be stopt the Blood may have a Passage by another These Unions Authors call Anastomosis The Veins have in their Cavities little Membranes or Valves disposed at certain distances in such a manner that they open towards the Heart and they shut towards the Extremities of the Body to hinder the Blood to return and to sustain it that by its weight it fall not back again There are more Valves in the Veins of the Thighs Legs Feet and of the Arms and Hands than in the other Parts of the Body There are none in the Vena Porta the Emulgent Veins nor in the Vena Pulmonaria The openings of the Valves are disposed alternatively to the end that the Blood which escapes or falls back from one may be stopt by the next Their Figure is almost like a Half-Moon their Substance is membranous fine and strong their number is uncertain The use of the Veins is to bring the Blood back again to the Heart from all the Parts of the Body SECT V. Of the Vena Porta ALL the Veins rise from two principal Trunks viz. The Porta and the Cava except that of the Lungs which is a particular Vein and separate from the rest The Vena Porta was so called by the Ancients because they thought that it brought the Chyle by its Meseraick branches from the Intestines to the Liver thorow whose Substance 't is spread as is said in the Section of the Liver It rises out of the Liver it sends out two small Veins to the Vesica Fellis called Cysticae Gemellae one to the Stomach called Gastrica Dextra then advancing a little to the left its trunk divides into two branches of which the least called Ramus Splenicus goes to the left Hypochondrium And the greatest called Mesenterica goes to the right The Ramus Splenicus so called because it carries the Blood from the Spleen sends out from its Trunk two branches called Gastrica Minor Maâ—â—â— which are spread thorow all the Stomach A branch of the Gastrica Major makes the Coronariae Stomachicae at the upper Orifice of the Stomach It gives three branches more two to the Omentum and Colon and the third to the Pancreas Then the Splenicus divides into two branches the one Superior the other Inferior The Superior sends out the Vas Breve and some other branches which go to the Spleen The Inferior gives two branches viz. The Epiplois Sinistra which is spread thorow the back Part of the Omentum and that Part of the Colon which is under the Stomach The other branch is the Gastro-Epiplois Sinistra which is also spread upon the Omentum and upon the Stomach it makes sometimes the Vena Haemorrhoidalis Interna The rest of this Inferior branch enters the Substance of the Spleen The right branch of the Porta called Vena Mesenterica before it divides sends out the Gastrâ—-Epiplois Dextra which is spread in the Omentum and lower Part of the Stomach it sends out also the Intestinalis which goes to the Duodenum and to the Jejunum it gives some branches to the Omentum and Pancreas Then the Mesenterica divides into three great branches which run betwixt the Duplicature of the Mesenterium two of them go towards the right side which divide into fourteen branches and these are again divided into an infinity of others less which are called Meseraicae they creep upon the Jejunum Ilium Caecum and Part of the Colon. The last and third branch of the Vena Mesenterica is spread thorow the middle of the Mesenterium to that Part of the Colon which is on the left side to the Rectum down to the Anus where it forms the Haemorrhoidales Internae The Use of this Vein is to bring back to the Liver the Blood which was brought by the Arteries to these several Parts SECT VI. Of the Trunk of the Cava Ascendens ALL the little Capillary branches of the Vena Cava which are spread thorow the Substance of the Liver unite by little and little into others which grow bigger and as they approach the Convex side of the Liver where they join all together and make up one large Trunk which comes out of the Liver and divides into two great big branches one of which goes towards the Heart and forms the Trunk called Ascendens the other goes downwards and is called Descendens Both the one and the other lie upon the Body of the Vertebrae on the right side of the Porta The Vena Cava Ascendens goes to the Claviculae before it divides but as it ascends to them it casts out three branches on each side The Phrenica or Diaphragmatica the Coronaria and the Intercostalis Superior Besides these three it sends out the 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉 or Vena fine Pari on the right side only The Phrenica comes from the Cava where it pierces the Diaphragma upon which it is spread It casts some branches to the Pericardium and Mediastinum Some Authors think that 't is by this Vein that the Pus of an Empiema is carried to the Kidneys and Bladder
divides into several more branches The third is the Vena Spermatica of which we have already spoken The fourth is the Vena Lumbaris which is not always one but often two or three on each side which they divide into Superior and Inferior they are bestowed on the Muscles of the Loins and on the Peritonaeum They sometimes call the last branch of the Lumbaris Muscula Superior There are some Anatomists that have observed that there is a branch of the Lumbaris that enters the Cavity of the Vertebrae and which ascends to the Brain which gave them occasion to think against all probability that the seed descended by that Vein from the Brain A little below the Emulgents the great Artery goes above the Cava and then the Cava divides into two branches called Iliaci because they pass above the Ilia to go to the Thighs Near this Division they send out one or two branches called Venae Sacrae they go to the Medulla of the Os Sacrum Then the Venae Iliacae divide into two branches the one Internal the other External The Internal sends out two branches the Muscula Media which is spread thorow the Muscles of the Thigh the Hypogastrica which is sometimes double it 's spread about the Sphincter of the Anus wherefore 't is called their Haemorrhoidalis Externa The Hypogastrica is spread also upon the Body of the Bladder upon the Matrix and its Neck therefore some thought without ground that the Menstrual Blood was discharged by this Vein which comes only from the Arteries The External branch of the Iliacae sends out three branches two before it goes out of the Peritonaeum and the third after it goes out of it The first is the Vena Epigastrica which comes rarely from the Cruralis it goes to the Peritonaeum ascends to the Musculi Recti where it Rencontres the Mammariae with which it communicates by Anastomosis The second is the Vena Pudenda 't is spread upon the Parts of Generation The third is the Muscula Inferior it goes towards the Articulation of the Remur and is distributed to the Muscles of this Part. The Iliaca Exterior after it hath sent out all these branches takes the name Cruralis and then sends out six branches more The first is the Vena Saphena which goes down under the Skin along the inside of the Thigh and Leg accompanied with a Nerve which loses it self at the inner Ankle The Saphena turns towards the upper Part of the Foot where it gives several branches of which some go to the great Toe The second is the Iscias Minor this Vein is little 't is spent on the Muscles and Skin which are about the upper Joint of the Femur The third is the Muscula Externa because it goes to the External Muscles of the Thigh on the other side of the Cruralis just opposite to the beginning of this Vein there goes out another called Muscula Interna which goes to the Internal Muscles of the Thigh The fourth is the Poplitaea made of two different branches united together it goes straight down by the Ham to the Heel it lies pretty deep upon which account it can hardly be opened The branches which appear in this place are not of this Vein The fifth is the Suralis which is pretty big and which divides into two branches the one External which is least the other Internal which is biggest Each of these branches divide again into two more the one External the other Internal The Suralis distributes its branches upon the fat of the Leg and makes with the branches of the Poplitaea all those Plexus of Veins which are conspicuous on the upper Part of the Foot The sixth and last branch of the Cruralis is the Iscias major which goes also to the Muscles and fat of the Leg and is divided afterwards into several branches which are distributed to the Toes SECT X. Of the Lymphatick Vessels I Have referred the Lymphatick Vessels till now because they do not properly belong to any particular Part of the Body They are small and Pellucide Canals which carry a thin and clear Liquor from all the Parts of the Body towards the Heart They have a fine transparent Coat their Cavity is full of Valves which open towards the Heart and which shut towards the Extremities Of these Lymphatick Vesels some rise from the Viscera as the Liver Spleen Lungs c. and others from the Glands which are spread thorow all the Parts of the Body They have no common Trunk nor Receptacle but they discharge themselves into different Vessels as they are nearest to them viz. the Receptacle of the Chyle the Ductus Thoracicus and the Subclavian Axillary Jugular and other great Veins The Lympha which the Vessels contain comes from the Serosity of the Blood which is separate in the Glands Some Authors think that it comes also from the Succus Nervosus which is brought by the Nerves to the Glands it 's ordinarily clear and transparent but it changes its colour according as 't is tinctured by the Chyle Bile Blood and other Humours 'T is insipid of it self but sometimes 't is acid salt or bitter It coagulates sometimes by the mixture of Liquors and dissolution of Salts as the Serosity of the Blood and when it 's dryed it has a particular Smell If you examine it Chymically you may draw from it much volatile but no fixt Salt some Phlegm and Sulphur and a little Earth Acids coagulate it and Volatile Spirits dissolve it The Lympha serves to liquisie the Chyle and Blood that thereby they may the more easily move Some think it serves to nourish and augment the Body But if we consider its Nature and the Parts it discharges it self into 't is more probable that 't is a proper Menstruum for the last and finest dissolution of the Chyle It hinders the dissipation of the Spirits it helps to make Fermentations it temperates the Acrimony of the Bile and Acids it dissolves Salts The breaking of the Lymphatick Vessels is often the cause of Dropsies SECT XI Of the Arteries in General WIllis hath demonstrated that the Arteries have four Coats as well as the Veins The first is thin and nervous its inner is woven of little Veins Arteries and Nerves whose Extremities terminate in the other Coats The second Coat adheres to the first in it there are an infinite number of little white Glands The third is musculous made of many Spiral Fibres which are close to one another The fourth and last is a Coat whose Fibres are in a straight Line The Blood which is necessary for the nourishment of these Coats is brought to them by the little Arteries and that which remains is brought back by the Veins the Serosity is separated by the Glands and the Animal Spirits are brought by the Nerves to the muscular Fibres of the Coats for the assisting the Pulse of the Arteries The beating of the Arteries as well as that of the Heart is nothing else
but what we call Systole and Diastole It is done as much by the Structures of the Fibres of the Heart and Arteries as by the Blood which being thrust with Violence by the Contraction of the Fibres of the Heart into the Aorta dilates its Fibres because it is thrust from a wide passage into a narrow one the Fibres being once dilated by their spring contract again and so thrust the Blood to their Extremities as fast as they receive it from the Heart The Use of the Arteries is to carry the Blood to all the Parts of the Body It is hard to distinguish the Capillary branches of the Arteries from those of the Veins if it is not by the Injection of tinctured Liquors The Capillary branches throughout all the Body unite with one another as well as with the Veins SECT XII Of the Trunk of the Aorta Ascendens THE Aorta coming from the left Ventricle of the Heart sends out two branches called Coronariae before it pierces the Pericardium but after it hath pierced it it ascends a little and then it crooks downwards and forms the Aorta Descendens From the upper side of this Crook it sends out three branches two on the left side which are one Subclavian and one Carotide one on the right side which is the right Subclavian from which immediately rises the right Carotide The Arteria Subclavia on each side send out the Mediastina the Intercostalis Superior the Mammaria the Cervicalis or Vertebralis and the Muscula which goes to the Muscles of the Neck of the Breast and to the Glandulae Thyroides After that the Subclavia hath passed thorow the Musculus Scalenus it is called Axillaris The Arteriae Carotides as they ascend on each side of the Trachea Arteria give some small branches to the Trachea Arteria to the Larynx to the Glandula Thyroides and then they divide into two branches the one Internal the other External The External Carotide sends out four branches The first goes to the Tongue to the Muscles of the Os Hyoides and to the Pharynx The second divides into two branches of which the first loses it self in the Muscles Milohyoides and Digastrici and the second goes along the basis of the lower Jaw and is lost in the Muscles of the Lips The third branch of the External Carotide divides at the Angle of the lower Jaw into two branches one enters into the lower Jaw and the other makes the Arteria Temporalis The fourth branch of the External Carotide goes to the Muscles on the hind Part of the Neck and to the Skin of the hind Head The Internal Carotide passes thorow the Canal in the Os Petrosum gives some branches to the Dura Mater joins with the Cervicalis sends out branches to the Glandula Pituitaria Plexus Choroides then it runs thorow all the Circumvolutions of the Cerebrum and Cerebellum and loses its Capillary branches in their Cortical Substance The Axillaris having pierced the Scalenum gives some little branches to the nearest Muscles it sends out the Thoracica Superior and Inferior the Scapularis and then it gives a branch which passes under the Head of the Humerus into the Musculus Longus and Brevis of the Arm. The Trunk of the Axillaris goes down the inside of the Arm giving branches by the way to the Muscles that lie upon the Humerus Above the Elbow it sends out a branch which is spread upon the Internal Condile of the Humerus At the bending of the Elbow this same Trunk divides into two branches the one External and the other Internal The External runs along the Radius it casts out a branch which goes to the Supinator and ascends to the Brachialis Internus in the rest of its course down to the Wrist it gives branches to the Longus Rotundus and benders of the Fingers Wrist and Thumb Being come to the Wrist it sends out a branch which goes to the beginning of the Tenar then it passes under the Tendon of the Flexor Pollicis it gives branches to the External Part of the Hand and it passes under the Muscles between the fore Finger and the Thumb to which it gives a branch on each side The Internal branch goes down along the Cubitus to the Wrist and is distributed to the middle Finger to the ring Finger and to the little Finger SECT XIII Of the Aorta Descendens THE Aorta Descendens sends out first the Bronchialis of M. Ruysch which accompanies all the branches of the Bronchiae A little lower it gives the Intercostalis Inferior the Phrenica which are distributed in the Diaphragma the Lumbaria which goes to the Muscles of the Loins and Psoas the Celiaca which divides into two branches the one on the right the other on the left of which the first gives the Gastrica Dextra which goes to the Stomach the Cisticae to the Gall-Bladder the Epiplois Dextra to the Omentum the Intestinalis to the Intestine Duodenum and to a Part of the Jejunum the Gastro-Epiplois to the Stomach to the Omentum and some branches to the Liver which enter the Capsula Communis to accompany the branches of the Vena Porta The left branch of the Caeliaca gives the Gastrica Dextra which is also spread on the Stomach the Epiplois Sinistra to the Omentum and the Splenica to the Substance of the Spleen Then the Aorta Descendens sends out the Mesenterica Superior the Renales or Adiposae which go to the Glandulae Renales and fat about the Reins the Emulgents to the Reins the Spermaticae to the Testicles the Lumbares Inferiores to the Muscles of the Loins the Mesenterica Inferior which with the Superior is distributed thorow all the Mesenterium and which accompanies all the branches of the Venae Meseraicae When the Aorta is come to the Os Sacrum it divides into two branches called Iliacae and before these branches go out of the Cavity of the lower Belly to go to the Thighs it sends out 4 or 5 branches The first is the Sacra which rises near the middle of the division and is spread in the lower Belly upon the Os Sacrum The second and the greatest is the Hypogastrica 't is distributed to the Bladder to the Rectum to the outer and inner side of the Matrix and to the Os Sacrum then it gives two considerable branches which go out of the lower Belly The first passes under the Pyriformis and is distributed to the Muscles called Glutaei The second which is lower than the first gives also two branches pretty big of which the first goes to the Obturatores the second pierces the Cavity of the Abdomen under the Pyriformis and loses it self by several branches in the Glutaeus Major The third is the Pudenda which passes under the Os Pubis goes to the Privities when this branch is wanting the Hypogastrica supplies its place The fourth is the Ilias Minor or Muscula Inferior it goes to the Muscle Iliacus transversus and Obliquus Ascendens