The Complete Engliíh 'Dijpenfatorj. Part II.

define diftinctly what Sleep is, or'ra-thcr (to avoid Confuiion and Dif-pute about Words) what differencethere is between an animal Bodywhen ajleep and when awake.

Firft then, there is no one butknows that in Sleep there is a Cef-fation from Action. When waking,we walk, difpute, move this orthat Limbic, but in natural orun-difturbed Reft, there is nothing ofsll thefe : that is, whereas being a-wake wc do perform lèverai Motionsby the ■voluntary Contractions ofour Muleles j when alleep, tholeMufcles only are contracted, wholeAction is in a manner involuntary,or to which the Mind has fo con-ftantly determin'd the Spirits, that itdoes it by a Habit, without the in-tervention of the rqaloning Faculty :fuch are tholè of the Hea-t andBrcift. So that there is it this timea kind of Relaxation or Looftnefs'il the moving Fibres of :he lèveraiMembers; or at leak ilich a quietPofmor. and State of them, bywhich all the antagonift Mufcles arein an EquHièrium and Equality ofAction, not overpowering one ano-ther. For this indeed fecms to beon'.: grçat Delign of Sleep, to îe-cever to the Parts overftretch'd bylabour, their former Force : andtherefore we do naturally, whencompoüng ourlelves to Rcß, putour Body into that Pofture, whichmoll favours the particularly wea-ty'd Limbs, and conduces to thisend.

In the next place, it is very plain,that there is in Sleep not only aReft, and a Sufpenfion for actingof moft of our bodily Organs, buteven oí our thinking Faculty too;that is,aceua;ionfrom lire h thoughts,as when waking we ave exerciicd a-kout, which we do reflect upon and

will, to employ our Mind with. Fortho Dreams are Thoughts, yet theyare imperfect and incoherent ones,and are indeed either fo faint andlanguid Reprelèntations, as to beconliftent with our Sleep, as fomemay be; or elle, if they be ftrongand lively, they are, as every oneknows, the Interruption and Diftur-bance of it. From hence it willfollow, that the Motion of the ar-terial Fluid mult be, c&teris paribus,more ièdate, even and regular, inthe time of flceping than waking.For belides the various Alterationswhich in the latter State this receivesfrom the feveral Paffions of theMind, the very Contractions of theMufcles themlelves in Exerciiès ofthe Body do differently forward itsCourfe ; whereas in Sleep, the Forceof the Heart and pectoral Mufcles,being more confiant and uniform,gives it a more calm and equallycontinu'd Impulfc. Hence alfo itwill come to pafs, that the Influxof the Liquor of the Nerves intothe Organs of the Body, as alfo itsReflux towards the Brain, is in Sleepeither none, or very inconfiderable :that is, that this Fluid has at thistime but little or no Motion. For'tis mulcular Action and Senfâtionthat require it tobe thus determin'd,this way or that, which are nowhardly any. And yet by the Arrivalof Blood at the Brain, this Juice willftill be feparated there, fit to be de-rived into its Canals or Tubes. Sothat by this means there will be akind oí Accumulation, or laying upin ftore, of Spirits, for the Officesand Requirements of Waking.

Thus we may, in ihort, look uponthe time of Watching as the timeof wearing out, or the Deftructionof the animal Fabric; and the timeot'Sleep as that in which it is repair'd

and