the Rib of the _Os Ilion_, and the inner part of the _Os Sacrum_, in
passing from whence it is joined to the last of the {34} Bastard Ribs, and
to the transverse Productions of the _Vertebra's_ of the Loins.
The _Extensors_ are the _Sacer_, and the _Semi-spinatus_, which make the
Waste streight, and are so interwoven along the Back-Bone, that one would
imagine that there were as many Pairs of Muscles as _Vertebra's_, affording
_Tendons_ to all.
The _Sacer_ springs from behind the _Os Sacrum_, as also from the hinder
and upper Extremity of the _Os Ilium_, and is inserted in the Spines of the
_Vertebra's_ of the Loins and Back.
The _Semi-spinatus_ hath its Source in the Spines of the _Os Sacrum_, and
is join'd to all the transverse Productions of the _Vertebra's_ from the
Back to the Neck, being exactly situated between the _Sacer_ and the
_Sacrolumbus_.
* * * * *
CHAP. IX.
_Of the Myology, or Anatomy of the Muscles of the lower Belly._
_How many Muscles are there in the lower Belly, and which be they?_
There are generally ten, five on each side, that is to say, two _Obliqui_,
one ascending, and the other descending; one _Transversus_, one _Rectus_,
and two Pyramidal, of which last, nevertheless, there is sometimes only
one, and sometimes none at all. {35}
The _Obliquus Descendens_, which is the first, hath its Original by
digitation in the sixth and seventh of the true Ribs, in all the spurious
Ribs, and in the transverse _Apophyses_ of the _Vertebra's_ of the Loins,
and comes near to the _Serratus Major Anticus_ of the Breast; from whence
it proceeds to the external Rib of the _Os Ilion_, and is terminated by a
large _Aponeurosis_ in the _Linea Alba_ or _White Line_, which separates
the Muscles that are on each side of the _Abdomen_ or lower Belly.
The _Obliquus Ascendens_ ariseth from its Source in the upper part of the
_Os Pubis_, and in the Ridge of the Hip-Bone, till it cleaves to the
_Apophyses_ of the _Vertebra's_ of the Loins in the Extremities of all the
Ribs, and in the _Xiphoides_ or Sword-like Cartilage, and is terminated in
the White Line by a large _Aponeurosis_.
The _Rectus_ being situated between the _Aponeuroses_ of the _Obliquus_,
takes its rise in the Cartilages of the Ribs, in the _Xiphoides_ and the
_Sternum_, and enters into the _Os Pubis_, having many nervous parts to
corroborate it in its length.
The _Transversus_ having its beginning in the transverse _Apophyses_ of the
_Vertebra's_ of the Loins, is fasten'd to the internal Rib of the _Os
Ilium_, and within the Cartilages of the lower Ribs, and is terminated by a
large _Aponeurosis_ in the _Linea Alba_, passing over the _Rectus_, and
sticking to the _Peritonaeum_.
The Oblique Muscles, and the Transverse, have Holes toward the Groin, to
give Passage to the Spermatick Vessels of Men, and to a round {36} ligament
of the _Matrix_ in Women; so that Ruptures or Burstenness happen through
these parts in both Sexes, although the Holes of these three Muscles are
not situated one over-against another.
The Pyramidal, so named by reason of its Figure, is situated in the lower
_Tendon_ of the _Rectus_, its Origine being in the upper and external part
of the _Os Pubis_; but it is terminated in the White Line, three Fingers
breadth above the _Pubes_, and sometimes even in the Navel itself. These
Muscles are not found in all Bodies for there are sometimes two, sometimes
only one, and sometimes none.
The use of the Muscles of the lower Belly is to compress all the contain'd
parts, in order to assist them in expelling the Excrements.
_How many Muscles are there in the Testicles?_
They have each of them one, call'd _Cremaster_; this Muscle takes its rise
from the Ligaments of the _Os Pubis_, and by the dilatation of its Tendon
covers the Testicle, which it draws upward.
_How many Muscles hath the _Penis_?_
It hath two Pair, _viz._ the _Erectores_ or _Directores_, and the
_Dilatantes_: The _Erectores_ arise from the internal part of the _Os
Ischion_, under the beginning of the _Corpora Cavernosa_, where they are
inserted, and retake their Fibres in their Membranes. The _Dilatantes_ or
_Acceleratores_ have their Source in the _Sphincter_ of the _Anus_ and
slipping from thence obliquely under the _Ureter_, are join'd to the
Membrane of the Nervous Bodies.
_How many Muscles are there in the _Clitoris_?_ {37}
It hath two Erectors which spring forth from the Protuberance of the _Os
Ischion_, and are inserted in the Nervous Bodies of the _Clitoris_. There
are also two others suppos'd to be its Elevators, which proceed from the
_Sphincter_ of the _Anus_, and are terminated in the _Clitoris_.
_How many Muscles are there in the _Anus_?_
There are three, _viz._ the _Sphincter_, and two _Levatores_. The
_Sphincter_ is two Fingers broad, to open and close the _Rectum_. This
Muscle being double, is fasten'd in the fore-part to the _Penis_ in Men,
and to the Neck of the _Matrix_ in Women, as also behind to the _Coccyx_,
and laterally to the Ligaments of the _Os Sacrum_, and the Hips.
The two _Levatores_ arise from the inner and lateral part of the _Os
Ischion_, and are fasten'd to the _Sphincter_ of the _Anus_, to lift it up
after the expulsion of the Excrements.
The _Bladder_ hath also a _Sphincter_ Muscle to open and shut its Orifice.
* * * * *
CHAP. X.
_Of the Muscles of the _Omoplatae_, or Shoulder-Blades, Arms, and Hands._
_How many ways doth the _Omoplata_ or Shoulder-Blade move, and what are its
Muscles?_
The _Omoplata_ moves upward, downward, forward, and backward, by the means
of four proper Muscles, which are the _Trapezius_, the {38} _Rhomboides_,
the proper _Levator_, and the lesser _Pectoral_, or _Serratus Minor
Anticus_.
The _Trapezius_ or _Cucullaris_ hath its beginning in the back part of the
_Occiput_, or hinder part of the Head, in the Spines of the six lower
_Vertebra's_ of the Neck, and of the nine upper of the Back, in passing
from whence it is implanted in the Spine of the _Omoplata_ or
Shoulder-Blade, and the external part of the _Clavicula_, as far as the
_Acromion_. This Muscle produceth many Motions by reason of its different
Fibres, drawing the Shoulder-Blade obliquely upward, downward, and forward.
The _Rhomboides_ is situated over the _Trapezius_, its rise being in the
_Apophyses_ of the three lower _Vertebra's_ of the Neck, and of the three
upper of the Back, but it is afterward join'd to the whole _Basis_ or Root
of the _Omoplata_, which it draws backward.
The proper _Levator_ commenceth in the _Transverse Apophyses_ of the four
first _Vertebra's_ of the Neck, by different Progressions, but is afterward
re-united, and inserted in the upper Corner of the _Omoplata_, which it
draws upward.
The _lesser Pectoral_, or _Serratus Minor Anticus_, is situated under the
great _Pectoral_, its rise being by Digitation or Indenting in the second,
third, and fourth of the upper Ribs, and its Insertion in the _Apophysis
Coracoides_ of the Shoulder-Blade, which it draws forward.
_How many Motions are there in the _Humerus_, or Arm; which be they, and
what are its Muscles?_ {39}
The Arm performs all sorts of Motions by the help of nine Muscles: For it
is lifted up by the _Deltoides_ and the _Infra-Spinatus_; it is depress'd
by the _Largissimus_, and the _Rotundus Major_; it is drawn forward by the
_Pectoralis Major_, and the _Coracoideus_; it is drawn backward by the
_Infra-Spinatus_, and the _Rotundus Minor_. It is drawn near the Ribs by
the _Subscapularis_, and its circular Motion is performed when all these
Muscles act together successively.
The _Deltoides_ or _Triangular_ hath its beginning in the whole Spine of
the _Omoplata_, the _Acromion_, and half the _Clavicula_, and by its point
cleaves with a strong _Tendon_ to the middle of the Arm.
The _Infra-Spinatus_ takes its rise in the Cavity that lies above the Spine
of the _Omoplata_, which it fills, passing over the _Acromion_, until it is
join'd to the Neck of the Shoulder-Bone, which it surrounds with a large
_Tendon_.
The _Largissimus_, otherwise call'd _Ani-scalptor_, covers almost the whole
Back, proceeding from a large and Nervous Stock, in the third and fourth
lower _Vertebra_ of the Back, the five _Vertebra's_ of the Loins, the Spine
of the _Os Sacrum_, the hinder part of the Lip of the Hip-Bone, and the
external part of the lower Bastard-Ribs, in passing from whence it
insinuates it self into the lower Corner of the _Omoplata_, as also into
the upper and inner part of the _Humerus_.
The _Rotundus Major_, or _Teres Major_, having its Origin in the external
Cavity of the lower Corner of the _Omoplata_, is confounded with the
_Largissimus_, and adheres with it by the same {40} _Tendon_ to the upper
and inner part of the _Humerus_, a little below the Head.
The greater _Pectoral_ hath its Source in half the _Clavicula_, on the side
of the _Sternum_; covers the fore-part of the Breast, and is fasten'd by a
short, broad, and nervous _Tendon_, to the top of the Shoulder-Bone, on the
inside, between the _Biceps_ and the _Deltoides_.
The _Coracoideus_ or _Coracobrachyaeus_, beginning in the _Apophysis
Coracoides_ of the _Omoplata_ or Shoulder-Blade, adheres to the middle of
the Arm on the inside, which with the _Pectoral_ it draws forward.
The _Infra-Spinatus_ fills the Cavity which lies below the Spine of the
_Omoplata_, its Origine being in the lower Rib of the _Omoplata_, from
whence it passeth between the Spine and the _Rotundus Minor_, to cleave to
the Neck of the Shoulder-Bone, which it embraceth, and draws backward.
The _Rotundus Minor_, or _Teres Minor_, proceeds from the lower Rib of the
_Omoplata_, and adheres to the Neck of the Shoulder-Bone with the
_Infra-Spinatus_ to draw it in like manner backward.
The _Sub-scapularis_ or _Immersus_ is situated entirely under the
_Omaplata_, proceeding from the internal Lip of the _Basis_ or Root of the
same _Omoplata_, and being terminated in the Neck of the Arm-Bone, which it
causeth to lie close to the Ribs.
_How many Motions are there in the_ Cubitus _or Elbow, and what are its
Muscles?_
The _Cubitus_ or _Ulna_ is endu'd with two sorts of Motions, _viz._ that of
Flection and that of {41} Extension, the former being perform'd by the help
of two Muscles, that is to say, the _Biceps_, and the _Brachiaeus
Internus_; and the later by eight others, which are the _Longus_, the
_Brevis_, the _Brachiaeus Externus_, and the _Anconeus_.
The _Biceps_ is a Muscle with two Heads, one whereof proceeds from the
_Apophysis Coracoides_, and the other from the Cartilaginous edge of the
_Glenoid_ Cavity of the _Omoplata_ or Shoulder-Blade: These two Heads
descend along the fore-part of the Arm, and are united in one and the same
Body, from whence springs forth a Ligament, which is inserted in a
tuberosity situated in the upper and fore-part of the _Radius_.
The _Brachiaeus Internus_ is a small fleshy Muscle, lying hid under the
_Biceps_, which takes its rise in the upper and fore-part of the _Humerus_,
and is implanted in the upper and inner-part of the _Radius_, to bend the
Elbow with the _Biceps_.
The first of the four Extenders is the _Longus_ having two Sources, _viz._
one situated in the lower Rib of the _Omoplata_, near its Neck, and the
other descending to the hinder-part of the Arm, till it is tyed to the
_Olecranum_ or _Ancon_, by a strong _Aponeurosis_, which is common thereto,
with the _Brevis_, and the _Brachiaeus Externus_.
The _Brevis_ or short Muscle of the Elbow arising from the hinder and
upper-part of the _Humerus_, is fasten'd to the _Olecranum_ with the
_Longus_.
The _Brachiaeus Externus_ is a fleshy Muscle which proceeds from the hinder
part of the {42} _Humerus_, and adheres to the _Olecranum_ with the
_Brevis_ and the _Longus_.
The _Anconeus_ or _Cubitalis_ being situated behind the Fold of the
_Cubitus_, is the least Muscle of all; it springs from the Extremity of the
Arm-Bone, at the end of the _Brevis_ and the _Longus_, and in descending is
inserted between the _Radius_ and the _Cubitus_ or _Ulna_, three or four
Fingers breadth below the _Olecranum_.
_How many Muscles hath the _Radius_, and which are its Motions?_
The _Radius_ is endu'd with a twofold Motion by the means of four Muscles:
Of these the _Rotundus_ and _Quadratus_ cause that of _Pronation_, as the
_Longus_ and the _Brevis_ that of _Supination_.
The _Pronator Superior Rotundus_, or round Muscle of the _Radius_,
commenceth from the inner _Apophysis_ of the Shoulder-Bone, in a very
fleshy Stock, and is terminated obliquely by a Membranous _Tendon_ in the
middle and exterior part of the _Radius_.
The _Pronator Inferior Quadratus_, springing forth from the bottom and
inside of the _Cubitus_, is fixt in the lower and outward part of the
_Radius_ by a Tail as large as its Head. This Muscle lying hid under the
others near the Wrist, is that which jointly with the _Rotundus_, turns the
Arm with the Palm of the Hand downward, which is the Motion of _Pronation_.
The _Longus_ is the first of the _Supinators_, whose Origine is three or
four Fingers breadth above the external _Apophysis_ of the Arm-Bone; from
whence it passeth along the _Radius_, and cleaves to the inner-part of its
lower _Apophysis_. {43}
The _Brevis_, or the second of the _Spinators_ arising from the lower part
of the _Inferior Condylus_, and the external of the _Humerus_, is twisted
round about the _Radius_, going forward from the hinder-part till it is
united to its upper and forepart. This Muscle, with the _Longus_, serves to
turn the Arm and the Palm of the Hand upward, and produceth the Motion of
_Supination_.
_How many sorts of Motions belong to the Wrist, and what are its Muscles_?
Two several Motions are perform'd by the Wrist, _viz._ one of Flection, and
the other of Extension, three Muscles being appropriated to the former, and
as many to the later: But it ought to be observed, that a strong Ligament,
call'd the _Annular_, appears here, which, surrounding all the _Tendons_ of
the Muscles as it were a Bracelet, holds them together, and elsewhere
serves to unite the two Bones of the Elbow. The three Flexors or Bending
Muscles of the Wrist are the _Cubitaeus Internus_, the _Radiaeus Internus_,
and the _Palmaris_.
The _Cubitaeus Internus_ derives its Original from the part of the
Arm-Bone, passeth under the Annular Ligament, and is ty'd by a thick
_Tendon_ to the small Bone of the Wrist, which is plac'd above the others.
The _Radiaeus Internus_ proceeds from the same place with the _Cubitaeus_,
and is fasten'd to the first Wrist-Bone which supports the Thumb. It lies
along the _Radius_, and passeth under the _Annular_ Ligament.
The _Palmaris_ is reckon'd among the Flexors of the Wrist, although
situated in the Palm of the Hand. It ariseth from the inner Process or Knob
{44} of the Arm-Bone, and is united by a large _Tendon_ to the first
_Phalanges_ of the Fingers, slipping under the Transverse or _Annular_
Ligament and sticking under the Skin of the Palm of the Hand.
The three extending Muscles of the Wrist are the _Cubitaeus Externus_, and
the _Radiaeus Externus_ or the _Longus_, and the _Brevis_.
The _Cubitaeus Externus_ taking its rise from the hinder-part of the Elbow,
passeth under the _Annular_ Ligament, and adheres to the upper and
outward-part of the Bone of the _Metacarpus_ that stayeth the little
Finger.
The _Radiaeus Externus_, or the _Longus_, having its Origine in the edge of
the lower part of the Arm-Bone, slides from thence along the _Radius_ on
the outside, extends it self under the _Annular_ Ligament, and cleaves to
the Wrist-Bone, which stayeth the Fore-Finger.
The _Brevis_ or _short_ Muscle of the Wrist springs from the lower part of
the same Edge; afterwards it runs along the _Radius_, passeth under the
_Annular_ Ligament, and is terminated in the Bone of the _Carpus_ or Wrist,
which stayeth the Middle Finger. But we must take notice, that besides
these six Muscles, there is also _Caro quaedam quadrata_, or a square piece
of Flesh under the _Palmaris_, which seems to arise from the _Thenar_, and
sticks to the eighth Wrist-Bone. It is supposed that this Musculous piece
of Flesh serves with the _Hypothenar_ of the little Finger, to make that
which is call'd _Diogenes's Cup_.
_How many Motions are there in the Fingers, and what are their Muscles_?
{45}
The Fingers are bent, extended, and turn'd from one side to the other by
the means of twenty-three Muscles, whereof ten are proper, and thirteen
common: The former are those that serve all the Fingers in general, and the
other those that are particularly serviceable to some of them: The Common
are the _Sublimis_, the _Profundus_, the common _Extensor_, the four
_Lumbricales_, and the six _Interossei_.
The _Sublimis_ or _Perforatus_, arising from the internal part of the lower
Process of the _Humerus_ or Shoulder-Bone is divided into four _Tendons_,
which run below the _Annular_ Ligament of the Wrist, and are inserted in
the second _Phalanx_ of the Bones of the four Fingers, after having stuck
in passing to those of the first _Phalanx_, to help to bend it. It is also
observed that every one of these _Tendons_ hath a small cleft in its
length, to let in the _Tendons_ of the _Profundus_.
The _Profundus_ or _Perforans_ lies under the _Sublimis_, deriving its
Original from the top of the _Cubitus_ and _Radius_. It creeps along these
two Bones, and is divided into four _Tendons_, which pass under the
_Annular_ Ligament, and slip into the Fissures of the _Tendons_ of the
_Sublimis_, to adhere to the third _Phalanx_ of the Fingers, which they
bend with the _Sublimis_: So that these two Muscles make together the
bending of the Fingers.
The _Extensor Magnus_ is that which extends the four Fingers. It springs
from the external and lower Process of the Arm-Bone, and is divided into
four flat _Tendons_, which pass under the _Annular_ Ligament, and cleave
{46} to the second and third _Phalanx_ of the Fingers.
The four _Lumbricales_ or _Vermiculares_ are in the Palm of the Hand, to
draw the Fingers to the Thumb: They proceed from the _Tendons_ of the
_Profundus_, and the _Annular_ Ligament, extend themselves along the sides
of the Fingers and are inserted in their second Articulation, to cause the
drawing toward the Thumb.
The three _Interossei Interni_, and the three _Externi_, are situated
between the four Bones of the _Metacarpium_, as well on the inside of the
Hand as without: They have their beginning in the Intervals or Spaces
between the Bones of the _Metacarpium_, are united with the _Lumbrical_,
and fixt in the last Articulation of the Bones of the Fingers, to produce
the Motion of drawing back or removing from the Thumb.
The Thumb is mov'd by five particular Muscles; one whereof serves to bend
it, two to extend it, one to remove it from the Fingers, and another to
draw it to them.
The _Flexor_ of the Thumb takes its rise from the upper and inner part of
the _Radius_, passes under the _Annular_ Ligament, as also under the
_Thenar_, and adheres to the first and second Bones of the same Thumb to
bend it.
The two _Extensors_ of the Thumb are the _Longior_ and the _Brevior_: The
former proceeding from the upper and outward part of the _Cubitus_, ascends
above the _Radius_, and is ty'd with a forked _Tendon_ to the second Bone
of the Thumb. The _Brevior_ hath the same Origin with the _Longior_, keeps
the same Track, passes under the _Annular_ Ligament, and is terminated in
the third Thumb-Bone. {47}
The _Thenar_ removes the Thumb from the Fingers, and forms that part which
is call'd the _Mount of Venus_: It hath its Source in the first Bone of the
_Carpus_ or Wrist, and the _Annular_ Ligament, and is inserted in its
second Bone.
The _Antithenar_ draws the Thumb to the other Fingers, having its Origine
in the Bone of the _Metacarpus_, that stayeth the middle Finger, and its
Insertion is in the first Bone of the Thumb.
The Muscle which serves to extend the Fore-Finger, is call'd _Indicator_:
It proceeds from the middle and outer part of the _Cubitus_, and is fixt by
a double _Tendon_ in the second Articulation of the Fore-Finger, as also in
the _Tendon_ of the great _Extensor_ of the Fingers.
That which draws the Fore-Finger to the Thumb is term'd _Adductor_: It
commenceth in the fore-part of the first Thumb-Bone, and is terminated in
the Bones of the Fore-Finger.
That which removes the Fore-Finger from the Thumb is known by the Name of
_Abductor_, which arising out of the external and middle part of the Bone
of the Elbow, and passing under the _Annular_ Ligament, cleaves to the
Lateral and outward part of the Bones of the Fore-Finger.
The Little-Finger hath two proper Muscles, _viz._ an _Extensor_ and an
_Abductor_.
The _Extensor_ springs from the lower part of the _Condylus_ of the
Arm-Bone, and is fasten'd by a double _Tendon_ in the second Articulation
of the Little-Finger, and in the _Tendon_ of the _Extensor_ of all the
others. {48}
The _Abductor_, call'd also _Hypothenar_, hath its beginning in the small
Bone of the Wrist, which is situated over the others, and is terminated in
the first Bone of the Little-Finger on the outside.
* * * * *
CHAP. XI.
_Of the Muscles of the Thighs, Legs, and Feet._
_What are the Motions of the Thighs?_
The Thigh performs five kinds of Motions; for it is bent, extended, drawn
within side and without, and turn'd round: All these Motions are produc'd
by the means of fourteen Muscles, _viz._ three _Flexors_, three
_Extensors_, three _Adductors_, three _Abductors_, and two _Obturators_ for
the Circular Motion.
The _Flexors_ of the Thigh are the _Psoas_, _Iliacus_, and _Pectineus_.
The _Psoas_ or _Lumbaris_ is situated inwardly in the _Abdomen_, on the
side of the _Vertebra's_. It proceeds from the transverse _Apophyses_ of
the two lower _Vertebra's_ of the Back, and of the upper of the Loins, and
lying on the inner Face of the _Os Ilion_, sticks to the lesser
_Trochanter_ or _Rotator_.
The _Iliacus Internus_ hath its Origine in all the Lips of the inner Cavity
of the _Os Ilion_, and being joyn'd by a _Tendon_ to the _Lumbaris_, is
inserted with it in the lesser _Trochanter_. {49}
The _Pectineus_ takes its rise from the fore-part of the _Os Pubis_, and is
united before to the Thigh-Bone a little below the lesser _Trochanter_.
The _Extensors_ of the Thigh are the _Glutaeus Major_, _Medius_, and
_Minimus_.
The _Glutaeus Major_ springs forth out of the lateral part of the _Os
Sacrum_, as also the hinder and outer part of the _Os Ilion_ and _Coccyx_,
and enters into the Thigh-Bone, four Fingers breadth below the great
_Trochanter_ or _Rotator_, being the thickest of all the Muscles of the
Body.
The _Glutaeus Medius_, deducing its Original from the hinder and outward
part of the _Os Ilion_, is inserted three Fingers breadth below the great
_Trochanter_.
The _Glutaeus Minimus_ ariseth from the bottom of the Cavity of the _Os
Ilion_, and is fasten'd to a small Hole near the great _Trochanter_.
The _Adductors_ of the Thigh are the _Triceps Superior, Medius_, and
_Inferior_.
The _Triceps Superior_ hath its beginning in the top of the _Os Pubis_, and
is terminated in the top of a Line, which is on the inside of the Thigh.
The _Triceps Medius_ proceeding from the middle of the _Os Pubis_, is
inserted in the Thigh-Bone a little lower than the _Triceps Superior_.
The _Triceps Inferior_ hath its Source in the bottom of the _Os Pubis_, and
is implanted in the Thigh-Bone, a little lower than the _Triceps Medius_.
Some Anatomists make only one Muscle of these three, attributing thereto
three Originals and three Insertions. These Muscles serve to draw the
Thighs one against another.
The _Abductors_ of the Thigh are the _Iliacus Externus_, or _Pyriformis_,
the _Quadratus_, and the _Gemelli_. {50}
The _Pyriformis_ arising from the upper and lateral part of the _Os
Sacrum_, and the the _Os Ilion_ cleaves to the Neck of the great
_Trochanter_.
The _Quadratus_ or square Muscle of the Thigh takes its Origine from the
external Prominence of the _Os Ischion_, and adheres to the outward part of
the great _Trochanter_.
The _Gemelli_ or Twin Muscles arise from two small Knobs in the hinder-part
of the _Ischion_ and insinuate themselves into a small Cavity in the Neck
of the great _Trochanter_.