Page:Cyclopaedia, Chambers - Volume 2.djvu/254

 MUS

(<k?)

1. All the Veflcls in an Animal, confifting of flexible, diftractile Fibres, are in a ftate of Tenfion ; i. e, are both ftretch'd tranfverfly and longitudinally by their contained Fluids: Thus* e, gr. let a Vein, or Artery be cut, and the oppofue Sides of the Veffel will contract, and come nearly to a contact about the Axis 5 while the two ends re- ceding both ways, leave a Chafm, which /hews that the VcfTel, while in its natural State, was diftended both ways ; and, confequently, that Contraftion in aJUheir Dimenfions, is the natural intrinfic Action of the Veffels or Fibres.

And the fame might be deduced, a priori, from the Growth of Animals 5 for by the increafed Quantity of the accumulated Blood, the Veffels mutt neceffarily be en- larged every way. _ Now, againft this diftending Power of the Fluids, the folid Mufcular Ftbrtlla continually exert a contractive, or reftimtive Force, by which they are kept in their proper State of Tenfion.

2. That this contractive Power of the Mufcular Fibres is a natural intrinfic Property of the Fibres themfelves, and does not depend on any Mixture, or mutual Action of Fluids, is evident from hence, that thefe Fibres retain the fame Property, after they are taken out of the Body and dried ; as we fee in Thongs, Cat-gut, and other fuch like Cords or Strings cut out of the Mufcular Coats and Skins of Animals, which may be ftretched out to a considerable length beyond their natural State 5 and when the {fetching Force or Weight is taken off, they will immediately con- tract again by their native Spring.

3. While a Mufcle contracts, the Blood is fqueezed out, and during its ftate of Contraction, it is more hard and folid than before 5 that is, it contains lefs Blood when contracted, than when ftretch'd ; which fhews, that the Contraction cannot be by the addition of another Fluid from the Nerves mixing with the Blood in the Mufcles.

4: No fiich Fluid in the Nerves could ever be found, as being mixed with the Blood, would occafion fuch Fermen- tation or Expansion. But fuppofing the Mufcular Cells thus inflated, no fuch effect could follow as fhortning the Mufcle in length, and fwelling it in thicknefs : But the Conference muft be, that the Mufcle would be lengthned as well as thickned 5 that is, it muft increafe its Dimensions proportionably every way, which is the proper Action of the Fluids on the Solids.

If then it be faid, that thefe Bladders, when the Mufcle is ftretched, are drawn into oblong Spheroids : and when inflated by the mixture of the nervous Fluid, reduced to a fpherical Figure 5 by which means their Axes are /hort- ned, and their conjugate Diameters enlarged : 'Tis an- fwer'd, that thofe f mall Veficles are foft, flexible, diflrac- tile, and equally yielding every way ; and fince an inclu- ded expanfive Fluid muft prefs its containing Veffels e- qually yielding every way, and equally expanfive 5 a Veffel, notwithstanding fuch Diftenfion, muft retain its natural Fi- gure, and be equally ftretch'd in all Directions.

Again, fince the Blood circulates freely thro thefe Mxf- CK/firCelts, it is plain, that as foon as they begin to inflate, it muft be immediately puflVd forward with an increafed Velocity in the Courfe of its Circulation, which muft pre- vent any fuch Inflation in the Mufcles. Before thefe Ve- hicles, therefore, can be diftended in the manner fuppos'd, the Exit of the Fluid muft be hindred ; that is, the Cir- culation muft be ftopt. If any one doubt of this, let him try whether he can blow up a Bladder, or other Veffel, that is open at both ends, and where the expanfive Fluid has as free an Egrcfs as Ingrefs.

Thus much premifed, the natural Action of a Mufcle will be eafily explain'd. From its Structure, it follows, that on the Contraction of its tranfverfe and fpiral Fibres, which are the Ramifications of the Nerves, the longitudi- nal, red, and flciliy Fibres, or Blood-Veffels, which con- ftirute the Body of the Mufcle, muft be fqueezed and drawn together, as being compell'd to follow the Motion of thefe elaflic Cords ; by which means the Blood-Veffels being comprefs'd, muft be forced, with fome Impctuofity, thro the Mufcle, and propell'd forward in the Courfe of its Circulation.

Now if the Blood fiiould hereupon flop, and return no more to the Mufcle, 'tis plain the Mufcle muft for ever re- main in this contracted State, as its proper and natural State of Quiefcence to which it tends, and where it would reft: But the Biood having receiv'd a frefh Impetus by the Con- traction, and returning upon the Mufcle in the Courfe of its Circulation, again rufhes into the Blood-Veffels, which being inlarged in all their Dimenfions by the Force of the returning Blood, the tranfverfe and fpiral nervous Fibre* muft be hereby ftretch'd, andthe Mufcle extended 5 by this means the Blood-Veffels being brought to their natural extent, and confequently the diftending Force of the Blood ceafing, the contractive Power of the Nerves will in that ftate begin to act again, and reftore themfelves with the fame Force by which they were extended, till the return- ing Blood re-enters the Mufcle, and ftretches it again.

MUS

MUSEUM, was originally ufed to fignify a Place in the Palace ot Alexandria, which took up at leal! a fourth part of the Cry ; fo call'd as being dcitm'd and fet apart to the Mujes, and the Sciences. S;e Muse.

Here were lodged and entertained a great number of learned Men, who wete divided into Companies or Colle- ProYeffcT'" 18 t0<heSciences or SeAs whereof they were

To each Houfe or College, was allotted a handfome Re- venue.

This Eitabli/hmcnt is atttibuted to Ptolemy Philadelphia, who here fixed his Library. See Lierary.

Hence the word Uufeum has pal's'd into a general Deno- mination, and is now apply'd to any Place fet apart as a Repo- sitory of Things that have fome immediate Relation to the Arts or the Mufes, whence the Word firtt took its Rife. See Repository, l$c.

_ The Mk.im at Oxford, call'd the Jfimolean MtlsjEusi, is a noble Pile erefled at the Expence of the Univerfity, for the promoting and carrying on feveral Parts of cutious and ufetul Learning. It was 'begun in 1S75), and finifhed in 1603 ; at which time, a valuable Collodion of Curiofi- ues wasprefented to the Univerfity by Ellas AJhmok Efq; and the lame day thete repofited, and afterwards digellcd and put in a jull otder by Dr. Plott, who was contlituted foil Keeper of the Mufxum.

Divers considerable Acceffions have heen fince made to the Mufxum ; as of Hieroglyphics, and other Egyptian An- tiquities by Dr. Huntingdon j of an entire Mummy by Mr. Goodyear ; of a Cabinet of natural Rarities by Dr. Lifter ; as alfo of divers Roman Antiquities, Altars, Medals, Lamps, £S?c.

Over the Entrance of the Mufeum is this Infcription ;

MUSjEUM ASHMOLEANUM, SCHOLA NATU- RALIS HISTORIC, OFFICINA CHYMICA.

MUSES, Fabulous Divinities of the antient Heathens,, who were fuppofed to prcfide over the Arts, and Sciences.

The Ancients admitted nine Mufes, and made them the Daugthers of Jupiter and Mhemofyne, or Memory.

Atfiril, indeed, their Number was but three, viz. Melete, Mneme, and Mde ; Greek Words fignifying Memory, Singing, and Meditation. Eut a certain Sculptor of Sicyox having Orders to make three Statues of the three Mufes foe the Temple of Apollo, and miffaking his Inftruaions, made three feveral Statues of each Muje ; thefe however were found fo beautiful, that they were all fet up in the Temple, and from that time they began to reckon nine Mufes : To whom Hefiod afterwards gave Names ', viz. Calliope, Clio,- Erato, Thalia, Melpomene, Terpfichtre, Euterpe, Polhymnia, and Urania.

Each of thefe were fuppofed to ptefide over their re- fpeflive Art ; Calliope ova Heroic Poetry ; Clio over Hifto- ry 5 Melpomene over Tragedy 5 Thalia over Comedy ; Eu- terpe over Wind-Mufic 5 Urania over Aftronomy ; Ter^- ficlore over the Harp ; Erato the Lute ; Polhymnia Rhetoric^

They are painted Young, Handfome, and Modell, a- greeably drefs'd and crown'd with Flowers. Their ufual Abodes were about Mount Helicon in hceotia, and Mount Par- tialis in the Tbtcide. Their Bufincfs was to celebrate the "Vifloriesof rhe Gods, and toinfpire and aflift the Poets 5 and hence the Cuihim of Invoking their Aid at the begin- ning of a Poem. See Invocation.

It muft not, however, be imagined, that the Deities thus invoked, ate confider'd even by the antient Poets themlelves as Divine Berfons, from whom they expeft any real Help. Under the Name of Mufe they wifh for the Genius of Poetry, and all the Conditions and Circum- itances neceflary fur a happy Execution of their Under- taking.

They are mere Allegories and Manners of exprefung them- felves poetically 5 as when they make Gods of Sleep, of Fame, of Revenge, and other natural and moral things. See God.

Accordingly, the Mufes arc of all Ages, Countries, and even of all Religions. There are Chriliian as well as Heathen Mufes, Latin, Grec/t, Englijb, French, &c. There are alfo new Mufes, which appear every day in favour of thofe who, difdaining things too ttite and common, chufc to ftrike out of the Road.

When Virgil wrote his Eclogues, he invoked the Sicilian Mufes, becaufe he imitated Theocritus ; and the Sicilian Poet having fucceeded ; the Roman begg'd for a Genius as happy as that of this Iflander.

'1 he Mufes of the Poet Lucretius had never infpired any Perfon before him. 'Tis plain, from rhe Doarine of his Book, what kind of Divinity it was he invoked. He ad- drefles himfelf to Venus, bur at the fame time tells us, that none of the Gods trouble themfelves with human Affairs. His Mufes therefore mull of neceffuy be mere Allegories.

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