Colonial North America: Countway Library of Medicine

89

Lect 7

are Cylindrical less in those, that are flat. It has been thought that the Marrow tended to render the Bones less brittle, but it seems rather designed to recieive those small Ends of Vessels, which Nourish the Bone, & to give an Oil to lubricate it - In the spongy Part of Bones, there are a Number of Cells lined with Membranes, which contain a reddish Liquor, which has been called a bloody Marrow, it owes its Colour to the Blood conveyed thro' the Fibres of the Bones as mentioned before. This is in much greater Quantity in Children, than Adults. Of the Periosteum - The Periosteum is a Membrane that surrounds all the Bones, except the Teeth & Ends of Bones for Articulation which are covered with a Cartilage to prevent Abrasion It serves to cover the Roughnesses of Bones, & assists the regular & easy Insertion of Blood Vessels into Bones & gives Insertion to such Muscles, as do not require a strong Ac= tion. It has very little Sensibility naturally, tho' when irritated serves to admonish the Mind of any injury done to the insensible Bone. It has a great Affinity to the Skin, as the Disorders, that affect the Skin generally affect

^Diseases Diseases wherein this oil becomes hardened as frequently near the skin of the Surface are usually attended with a turnover which is called a [?] and are generally cured by integrating the part - out of the Body ^{[a put?]} this oil frequently ^{Oil & [?]} concretes by Cold as is seen in [?], which seems to differ from the fluid Oil only in that it contains Less Water

Use of the fat

The Use of the Adeps or fat are various ^{for Nutrition [?] a priori} It's subserviency to the Purpose of Nutrition is easily inferred a priori from it, [?]ing an oil and Salt ^[Earth?] in large Proportion which render it more nutritive than any other of the common fluids of the body and Experiments ^which have been used to ascertain the truth have [?] established the fact for Animals which have been fed principally on oily substance, [universally?] fatten the fastest - It has also been fully proved that ^{not subject to Putrefaction} there is no Part of the animal Body less subject to putre= faction than the fat a circumstance which must surely be very important in the nutritious fluids -

90

Lect 7

it. E. G. The Lues venerea, w^h. affects the Glands under the Skin do also affect it. Certain Nodi are formed, which some have thought to be pro= tuberances of the Bone tho' they are nothing, but the injured Periostium hardened into that Substance. Mercury cannot affect these, & therefore before a Co= urse of Mercury or Salivation is given, these Nodi or Knots should be first laid open, that the Mercury may penetrante them, & so effect the [?], otherw= ise, they will be untouched by the Salivation, & conseq= uently will require to be opened afterwards, & need a second Course before a radical Cure can be effected. The Bones are insensible in themselves, yet the little red Spots that arise after Exfoliations, & when a Bone is amputated are extremely sensible, because the Nerves in Bones being compressed by the strong Fibres or Lamina of the Bone cannot exert their natural Sensibility yet when their Terminations get clear of the Confinement of the Bones, they become very sensible in these Spots. The Marrow also of Bones, tho' long thought to be possesses of a high Degree of sensibility. Yet from Experiments, is found to be very little. The Periosteum is of a Texture softer than Bone, & harder than Muscles, & therefore

That fat is used in the animal Body for the purpose of Nutrition is also apparent ^{a posteriori or} from what is frequently observed to take place in the body

^{a posteriori [?] Consumption of it in fasting Animals} In fasting animal, the fat contained in the Adipose Membrane is often very rapidly absorbed into the body and most of those which sleep much in the Winter or which are not capable of [furnishing?] themselves with food at that Season it is very generally observed that they grew entirely fat as colder weather advances and yet in the spring they are ^Diseases invariably observed to have become lean

^Consumptions In most diseases of the body especially in Consumptions the same thing obtains and the adipose Substance seems to be that upon the Consumption of which the Emaciation of the Subject almost entirely depends for the organized [?] to be in this ^{all that} cases very nearly the same

^{[?] Excercise} By excercise also the Oil appears to be taken up into the Vessells and the fattest of Animals become in a short time lean [??] and by Rest or Idleness it is generally accumulated

^{for [?]} It is supposed to have been formed by nature also for the purpose filling up Cavities and giving a uniform and regular figure to the body - to form a [?] as it were for other parts of ^{for support} the body to rest on as E G. in the Eye which is supported a large Quantity of this Substance within the Orbit

^{a Defence from Cold} Probably it also serves the purpose of defending the body from Cold for all is exceedingly well calculated for such

91

Lect. 7.

& therefore preserves the Fibres of the Muscles from being abraded by the Bones. It is of great Use as to the Blood Vessels, whose capillary Extremities enter the Bones, & might be easily cut in two, if it was not for this Membrane, & so the Body of the Bone Would be deformed of its Nourishment. Great Care is requisite in Fractures - & great Danger is sometimes to be apprehend= ed for the Periostium being firm often does much misch= ief by confining Corrupted Matter between it & y^e Bone & bringing on a Caries of the latter, which Matter, if it could be discovered soon enough; might be dislodged by an Incision & bad Consequences prevented - The Bones often become caries in the Lues Venerea - The Perios= teum has many Nerves, but not very sensible, unless disc[?] - Of Cartilages. A Cartilage is a smooth solid gristly & elastic Substance, softer than a Bone, & harder than a Ligament - They serve 3 Purposes, 1^st to prevent the Bones abrading each other, as the Patella in y^e Joint of y^e Knee, or as in the Os Femoris, & Tibia, where the Cartilages are nearly annular, & serve as a loose Ring between the Parts of Hookhinges of heavy Gates - 2^d. They give Shape to the Parts, as those of the outer Ear & Nose

a Use and in cold Climates Animals are generally observed to be [?] largely supplied with fat whereas in warm they are generally very lean - - The Indians use it to defend the parts from Cold

^{Use of Mucus in Infants} The large Quantity of Mucus contained under the Skin in Infants seems to have been furnished them with a View to defend their [?] bodies from the Action of Cold to ^{Injuries from} which they are much more exposed than adults - in the latter the Power of resistance to any offending Cause from the strength und firmness of the fibres is [amply?] suficient ^{for Preservation & Comfort} without so coping a provision of this very useful Substance and accordingly nature ^{who has formed nothing in vain} attentive to the necessities of her has been ^{with a} [?] [rare?] sparing Hand allotted them their Portion -

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Lect 7

3.^d

They keep the Part in their proper Situa= tion, as appears, where they unite the Ribs with the Sternum, being pliable, they move, easily in Respira= tion, & permit the Body to move readily to either Side - All the Ends of Bones destined for Motion are tipped with Cartilages, which also are covered with a Membrane cal= led Perichondrium -

Of Ligaments -

A Ligament is a white solid Body, softer than a Carti= lage, & harder than a Membrane. Their Use is to bind Parts together. They join all moving Bones together & prevent Dislocation. They sometimes surround the Joints like a Purse or Bag, & contain the Synovia, espe cially where there is a Rotatory Motion. The Ligam= ents of those Joints, that admit only of Flexion & Exten= sion, are shorter, thicker & stronger on the Sides, than they are before & behind the Joint, except in the Joint of the Knee, where the strongest Part of the Ligament is behind which Structure is necessary to raise the Leg in Walking. There are two strong Ligaments, where the Os Femoris is articulated with the Osoa Innominata to prevent Dis= location, by reason of which it very seldom happens. Some Ligaments run in a Transverse Direction

Lecture 6^th 1785 continued

On Ligaments -

^{their Organis[?]} Next to cellular Membrane the Ligaments appear to be the most simple or least organized Solids of the animal Body they contain the largest proportion of Earth in their Composition Bones & Cartilages only excepted.

They are found in a great number of Parts of the Body and more particularly about the joints of the Bones

they are thicker and firmer than simple Membranes but not so much so as Cartilages they are generally with Difficulty stretched and ended with but a small [?] of Elasticity, or Sensibility After Maceration in water for a considerable Length of time they may easily be divided into a number of different Layers or lamina each of which appears to be formed by fibres the largest of which are disposed in a longitudinal Direction and the smaller in a transverse - and a number of nerves [?] into their formation

The difference in the Colour and Properties of Liga= ments have given Occasion to distinguish them by a Division into two Classes - elastic and inelastic -

Elastic Ligaments

are of a yellow colour and less organized than the other [?] they have a number of Vessells spread upon their Surface but

muscular fibres themselves - -

The fascies as they are called of muscles, usually known by the name of the [?]dinous Expansions, or [?] of Muscle because they were considered ^believed by the Ancients to [?] from nerves are properly ^also to be considered as of the same nature with tendons - these are found in various parts of the Body and are doubtless joined on generally to the sides or Edges of muscles in a similar Manner -

both tendons and Aponeuroses are considerably Vascular being supplied with fluids [thoug?] generally with such as are [?] [?] red Blood - -

Use of inelastic Ligaments

The capsular Ligaments are obviously designed to prevent the bones to which they are attached from being luxated or in any Degree put out of their places - they generally admit of considerable Motion especially [?] the larger joints - -

It is universally observed that [?], the Motion of the part is greatest the Strength of the Ligament is weakest whence it [?] ^{is to [?]} that strength and large Motion as dependent on the Ligaments are incompatible whith each other An example of this is seen in the Joint of the fore Arm with the Humerus, the strongest part of the Ligament here being behind where the motion is evidently most confined

The inter Ligaments connect the bones the [corpal?] form a [Ring?] of [?] The tendons are attached to the Extremities of Muscles and are usually inferred into the neighbouring bone by this Mechanism they serve the purpose of binding or tying these Muscles to the Bones and thereby enabling them to exert their Powers upon the Levers of the Body - - -

tendinous Expansion cover muscular parts and in some Cases form a complete Vagina or sheath for a neighbouring Muscle to act in - this is exemplified in the Abdomen where the [?] of each Side is found to be completely inclosed in a sheath of this kind formed by the tendinous Expansions of the other abdominal Muscles -

Diseases of Ligaments

Though Ligaments are generally in their natural sound state in a great measure insensible yet it easily proves that they are furnished with a considerable number of nervous fibres - their small Degree of Sensibily in a healthy state has usually been imported to the compact structure of the tendons which it was supposed compressed the Nerves in such Degree or to destroy the communication of the nervous Influence; but ^{there are} many Diseases which do not appear to alter the Consistency of these fibres & yet are often attended with great Sensibily & even extreme pain -