of mine having pil'd up many Cart-loads of these Brass-lumps in a Barn of his for some secret purposes of his own the Roof letting rain-water fall copiously in amongst them they all began to smoak and at last to take fire and burnt like red hot Coals so that the Town was in an uproar about quenching of them and one thing further I took special notice of in this unlucky Experiment that the Water which drained from the quenching of them left little pieces and Crystals of Copperase sticking all along to the Piles of Grass that grew in the Croft it run down Thus Antimony and Sublimate being mixed together will grow so hot the one relaxing the fermenting spirit in the other that they are not to be touched Thus in the Corrosion of Mettals by Aqua fortis what a strong heat is there in the Liquor and what a steam constantly evaporates during their fermentation In the Commixtion of Oyl of Vitriol with Oyl of Tartar per deliquium what a violent heat and effervescence do presently arise besides a sharp and acrimonious vapour that strikes our nostrils Nay and we see our Subterraneous Damps do sometimes with intermixtion with the moist Air grow to that over-height of fermentation that they fire of themselves and strike down all before them Thus the Spirit of Niter mixed with Butter of Antimony grows so hot that it is ready to rise in a flame Thus certainly do all Baths receive their heat from Mineral Vapours or the Minerals themselves being in solutis Principiis and so the fermenting Spirit sets a playing in them as the Learned Doctor Jordan did most rationally conjecture This universal fermenting Spirit does not onely play these feats in the Mineral but also operates in the same manner in the Vegetable Kingdome which we ocularly behold in the Artifice of Malt where the Grains of Barly being moistned with water the parts are relaxed the internal Spirits in them are dilated and put into action and the superfluity of water being removed which might choak it and the Barly being layd up in heaps the fermentation and heat presently appears with a kind of vinous steam and effluviums which passe from it and therefore it shoots forth into Spires Thus we see in wet-Hay how the spirits work not onely to a heat but if they be not cooled and prevented by Ventilation they break out into a flame also Nay in all Vegetables there is this constant Heat though it be below our Sensation as it is in some Fishes and colder Animals also and a constant steam and transpiration of particles as we have experimentally proved in our XXV Observation And now let us pursue these Spirits into the Animal Kingdom and we shall see that they have the like effects and operations there also as is formerly observed onely being there in greater plenty and more purely refined and in a constant state of Fusion and Volatility they work nobler effects Now the Spirits that are lodged in all the meats and drinks we receive being more or less fixed therein What does the Soul but like an excellent Chymist in this internal Laboratory of Man by a fermentation of our nourishment in the stomach and guts a filtration thereof through the Lacteae a digestion in the Heart a Circulation and Rectification in the Veins and Arteries what does she I say by these several Physico-Chymical operations but strive all this while to unfix exalt and volatilize the Spirits conteined in our nutriment that so they may be transmitted to the Brain and its divarications and in that reconditory kept and reposited for her use and service So that these we now call Animal Spirits are the purest subtlest and most volatile particles and activest Atoms of the bloud which by continual pulsation of the Heart are carried with the bloud by the carotidal Arteries up into the Brain and there by that lax and boggy substance are imbibed and separated from the bloud and thence by the Spinal Marrow and Nerves transmitted to all the parts of the Body Now as the Chyle is perfected in the stomach and guts and their appendent Vessels the lacteal Veins and as the bloud is perfected in the Heart and it s annexed Vessels the Veins and Arteries so the Animal Spirits are separated preserved and perfected in the Brain with its continued trunk and branches viz. the Spinal Marrow Nerves and Fibers for the uses hereafter to be declared Now the two former Liquors the Chyle and the Bloud because of their grosser liquidity need to be conveyed in hollow Pipes and Channels viz. the Veins and Arteries but the Spirits which is the quintessence of them both can easily pass by a swift filtration through the Brain Spinal Marrow and Nerves Membranes and Fibers which are as it were the Cords Sayls and Tackling to move this Engine or Vessel we call the Body Nay though we can give you no sensible eviction of it Why may not all those long filaments of which the substance of the Brain Spinal Marrow and Nerves consists be tubulous and hollow so that the Animal-Spirits may be channelled through them as the bloud through the Veins and Arteries I am sure we see by Observation xxxi and L. what infinitely small filaments and vessels there are in Animals and yet all tubulous and perforated so that the suddain inflation of all those capillary threads or pipes may serve for Motion of the Body and the constant though flower filtration of the Spirits through their Coats and Cylindrical Membranes may serve for Sensation So that it seems this Cottage of Clay with all its Furniture within it was but made in subserviency to the Animal Spirits for the extraction separation and depuration of which the whole Body and all the Organs and Utensils therein are but instrumentally contrived and preparatorily designed Just as the Chymical Elaboratory with all its Furnaces Crucibles Stills Retorts Cucurbits Matrats Bolt-heads Pelicans c. were made for no other end by the ingenious Chymist than for the extraction and depuration of his Spirits and Quintessences which he draws from those Bodies he deals with in the obtainment of which he hath come to the ultimate design of his indeavours Now as in Minerals and Vegetables the colluctancy of these fermenting Spirits with the grosser matter does both create a constant heat and evaporation of Atoms So in Animals the like is more eminently conspicuous to wit the vital heat or calidum innatum and those fuliginous effluviums which pass constantly out of us by insensible transpiration which Sanctorius hath proved to exceed the bulk and weight of all our sensible Evacuations whatsoever Having thus demonstrated how the Soul obtains these Spirits after her several operations of Digestion Chylification Sanguification Circulation c. the like now let us see what use she makes of so pretious a substance First therefore we affirm that this thin and spirituous matter which is called the Animal Spirits is the immediate Instrument of the Soul in
all her operations both of Sense and Motion First for sense it is plain by what is discovered in a Vertigo for the Brain it self is not of such a fluid substance as to turn round and make all objects to do so too wherefore t is a sign that the immediate corporeal instrument of conveying the images of things is the Spirits in the Brain Secondly That they are the chief Engine of Sight is plain not onely because the eye is full of these livid Spirits but also because dimness of sight comes from deficiency of them though the parts of the eye otherwayes be entire enough as in sick and old persons and in those troubled with an Amaurosis or Gutta Serena I had the last year a Patient a young Boy of seventeen years old who fell casually stark blind of his right eye in which you could outwardly discover no fault at all the Disease being an Amaurosis or obstruction of the Optick Nerve for that Nerve being by successful means disobstructed and relaxed so that the Animal Spirits were able to flow done to the Retina again he shortly after perfectly recovered his sight again without any relapse at all to this present day Thirdly If you cast a Ligature upon any Nerve you destroy both the sense and motion of that part whither that Nerve was propagated as by that pleasant Experiment by tying the recurrent Nerves in a living Dogg we have tryed till by relaxing the Ligature the Spirits may have the freedome to channel into the Nerves again Which truth is also handsomely made out by that ordinary example of a mans Leg being asleep as we call it for by compression of the Nerves the propagation of the Spirits into the part is hindred for as sense and motion is restored you may feel something creep into the Leg tingling and stinging like Pismires as Spigelius compares it which is the return of the Animal Spirits into that part again Fourthly That Spontaneous motion is performed by continuation of the Animal Spirits from the common Sensorium to the Muscle which is the gross Engine of Motion is sensibly evinced in dead Palsies where one side is taken away To all which add the former Observation of the Spirits circumundulation when the Snail at any time moved and of their joint quiescency together Having now shown you how these Animal Spirits are generated in our Body or to speak more properly disimprisoned and separated from our nutriment and so from fixation brought through Fusion to Volatilization having also shown you what use Nature makes of them in Sensation and Motion let us screw our Enquiry a little further and see if we can discover how the Spirits move in the Brain and Nerves to perform the same operations First therefore we affirm that a lesser quantity and slower motion of the Spirits is required for Sensation than there is for Motion for in this the Muscle swells that moves the part which is a plain Indication of a greater influx of Spirits directed thither a greater I say for I do not deny but there is required to sensation a moderate quantity and diffusion of the Spirits into all the parts of the Body else we should alwayes be benummed and stupid as when our Leg is asleep by an interception of the Spirits Secondly that their motion is slower in sensation then motion the former Experiment of the Snail does also manifest whose Animal Spirits never begin to undulate till she begin to move whereas she is sensible when they are in Quiescency as you may by pricking her with a Needle easily observe Thirdly in the return of the Spirits into the stupefied Leg we plainly perceive by the prickling what a flow motion the Spirits have All which Phaenomena do seem to favour our former Conjecture that for Motion the Spirits move impetuously down the nervous filaments which are hollow but for Sensation they onely creep by a filtration down their Coats and Membranes Now these Spirits being so subtle and dissipable the Soul spends them every day in using of them and they being much spent she can hardly move the Body any longer The sense whereof we call Lassitude For certainly as Doctor More very ingeniously inferrs if it were an immediate faculty of the Soul to contribute Motion to any matter I do not understand that Faculty never failing nor diminishing no more than the Soul it self can fail or diminish that we should ever be weary Thus are the Phaenomena of Sense and Motion best salved whilst we are awake now what happens when we sleep is a matter of further enquiry Some have defined Sleep to be a migration of all the Spirits out of the Brain into the exteriour parts of the Body whereas by our former Observations it may rather seem to the contrary that is The retraction of the Spirits into the Brain or at least a restagnation of them in the nervous parts does till Nature being recruited by a new supply and regeneration of them in the Brain direct them into the Spinal Marrow and Nerves which being replenished with them again they run their current as before so the whole Animal thereby is made capable of feeling the Impulses of any external object whatever which we call Walking and during this Interval and Non-tearm of sensation for so we may without a Complement call Sleep why may not the Soul be retracted and wholly intent upon and busied about her Vegetative and Plastical Operations So that when she has locked up the doors of this Laboratory the Body she may be busie in augmenting repairing and regenerating all the Organs and Utensils within and painting and plaistring the Walls without This I am sure we observe to be the greatest part of her obscure employment in the Womb where the Embryo for the most part sleeps whilst the Soul is in full exercise of her Plastick and Organo-Poïetical Faculty Now these Animal Spirits being continually transmitted from the Brain through the Spinal Marrow Nerves Tendons Fibers into all the parts of the Body especially whilst we are awaking may some of them at least have a kind of circulation for those which perspire not having lost their motion may either mix with the bloud in habitu partium or relapse into a kind of insipid phlegm as Chymical Spirits do that are not purely rectified and to be returned back by the Lymphiducts again Lastly I have but one paradoxical and extravagant Quaere to make and that is this That since we have proved these Animal Spirits to be the ultimate result of all the concoctions of the Body the very top and perfection of all Nature's operations the purest and most aetherial particles of all Bodies in the World whatsoever and so consequently of nearest alliance to Spiritualities and the sole and immediate instrument of all the Soul's operations here even in statu conjuncto the Body and the Organs thereof being but secondary and subservient Instruments to the Spirits These things being thus premised may
to be tubulous and hollow And therefore however though the learned Doctor Brown my ever honoured friend hath ranked this conceit of the Eyes of a Snail and especially their quadruplicity amongst the Vulgar errours of the multitude yet through a good Microscope he may easily see his own errour and Nature's most admirable variety in the plurality paucity and anomalous Situation of eyes and the various fabrick and motion of that excellent organ as our Observations will more particularly inform him If by a dextrous Dissection you would see the internal Fabrick of this Animal there are many excellent things that will recompence your curiosity For first you may find her Heart just over against that round hole near her neck which Doctor Harvey ingeniously conjectures to be the place of their respiration which hole you may observe to open and shut as she moves or stands still and out of which I have observed some salivous Matter to be evacuated We have observ'd her Heart to beat fairly for a quarter of an hour after her dissection afterwards we took out her guts which were of a pure green colour by reason of the thinness of their film and transparency of the green juice of hearbs with which they were repleated They were all diaper'd or branched over with pure white Capillary little veins which by help of the Microscope we could discern to be hollow with a blackish kind of pith running through the midst of the smallest of them which doubtless was their nutrimental juice coagulated there like the bloud starkn'd in the veins of dead Animals They are mouthed like a Hare or Rabbit with four or six needle-teeth like those in Leeches Nay this poor Animal how contemptible soever it may seem hath a whole Sett of the same parts and organs with other Animals as Heart Liver Spleen Stomach Guts Mouth and Teeth Veins and Arteries Yea and a pair more of the noblest of the Senses the Eyes Nay this Animal doth autoptically evince us that as sanguineous and more perfect Animals have a circulation of their bloud within them so this more ignoble creature hath also a circulation of its nutritive humour which is to it as Bloud is to other Animals Nay further which is the best Remarkable of all this juice hath not onely a circular motion but also the very Animal Spirits by which she moves seem to have the like Circulation For if you observe her with the bare eye to creep up the sides of a glass you shall see a little stream of clouds channel up her belly from her tail to her head which never return again the same way but probably go backwards again from the head down the back to the tail and thus so long as she is in local motion they retain their circulation which is a pleasant spectacle And more pleasant if you let her creep upon the lower side of your glass-object-plate and so view that wavy Current of Spirits through the Microscope which handsome experiment does not onely prove the Spirit 's circular motion but also ocularly demonstrates that the Animal Spirits are the Soul 's immediate instrument in all Loco-motion Now if you reply that it is onely the parts of her body that moving by a kind of undulation protrude one another forwards as Palmer-worms which we call Wool-boys and some sort of Caterpillars do To this I answer that do but intensly observe any one of the former spots or clouds and you shall see it go quite along from the tail to the head keeping alwayes an equal distance from the precedent and subsequent spot so that it is far more ingenious to believe it to be a gale of Animal Spirits that moving from her head along her back to her tail and thence along her belly to her head again is the cause of her progressive motion OBSERVAT. XXII Of Lampreys THe Lamprey hath seven holes or cavities on eiside three or four and no gills at all as other fishes have whence the common people through ignorance of these cavities and their proper use in nature have affirmed them to be Eyes an errour so gross and palpable that it needs not the Microscope to refute it For these holes or sluces do indeed supply the defect of gills and are assisted by the conduit in the head for like Cetaceous Animals the Lamprey hath a fistula spout or pipe at the back part of the head whereat they spirt out water so that both these cavities and the head-pipe together do very neatly supply the defect of gills and execute their office of receiving and ejecting water again These sluces and the fistula shoot themselves slopewise and not straight forwards into the cavity of her neck The Heart in this Animal is very strangely secured lies immured or capsulated in a Cartilage or grisly substance which includes the Heart and its Auricle as the Scull or Pericranium does the Brains in other Animals it is of a horny and transparent substance of an obtuse conical figure cemented and glewed as it were on all sides to the Pleura or innermost skin of the Thorax the Cone or obtuse Tip of this Capsula butts or shoots it self into the basis of the Liver which to give way thereunto has an oval cavity or hollowness exactly fit to receive it In this Cartilaginous Pericardium or purse of the heart is likewise the Auricle co-included lying not upon the basis of the heart as in other Animals but laterally adjacent thereunto insomuch that it being far more flaggy then the heart they seem to represent the right and left ventricle of the heart Yet is the Heart not onely more solid but seated in the right side and the Auricle in the left If the Lamprey be laid upon her back and you gently lift up with a probe the Heart and Auricle you shall see a fine thin Membrane arise which separates the Heart from the Auricle as the falx cerebri does separate the left side of the brain from the right From this Auricle proceeds a little short Channel which perforates this separating Membrane and brings the bloud from the auricle into the heart we thrust a probe just under this Channel betwixt the Heart and the Auricle to see the bloud passe from the Auricle into the Heart for at every pulse of the Auricle you might see the bloud passe through this Channel into the heart for alwayes as the bloud passed through it was blew and when empty pale and transparent that I could easily see the Probe thorow it Whilest I had the Probe in this position with another Instrument and it together I quite stopped the Channel on purpose to hinder the bloud from coming into the heart which thereupon grew very pale and in a short time ceased its motion the Auricle in the interim swelled and was very red I no sooner opened the Channel to let the bloud have a free passage as formerly but the heart began afresh to beat again We pricked the heart while it
nay and probably into the diaphanous humours also are not discernable but when they are preter-naturally distended in an Ophthalmia and so grow turgent and conspicuous To which we may adde that in most quick Fish though you cut a piece of their flesh off yet will no bloud be discernable though they be sanguineous Animals but the bloud is so divided by the minuteness of their Capillary Vessels or percribration through the habit of the Parts that either it has lost its redness or our eyes are not able to discover its tincture Secondly It is observable also from the former Experiments that in these minute Animals their nutritive Liquor never arises to the perfection of bloud but continually as it were remains Chyle within them for want of a higher heat to dye it into that Spirituous Liquor Nay you shall observe in perfect Sanguineous Animals a Circulation of an albugineous chylie-matter before the bloud have a being if you take Nature at the rise and critically observe her in her rudimental and obscure beginnings For view but an Egge after the second day's Incubation and you shall see the cicatricula in the Yolk dilated to the breadth of a groat or six-pence into transparent concentrical circles in the Centre whereof is a white Spot with small white threads which in futurity proves the Heart with its Veins and arteries but at present both its motion and circulation is undiscernable to the bare eye by reason of the feebleness thereof and also because both the Liquor and its Vessels were concolour to the white of the Eggs they swum in but the Heart does circulate this serous diaphanous Liquor before by a higher heat it be turned into bloud And one thing here I am tempted to annex which is a pretty and beneficial Observation of the Microscope and that is That as soon as ever you can see this red pulsing Particle appear which Doctor Harvey conceited not to be the Heart but one of its Auricles you shall most distinctly see it to be the whole Heart with both Auricles and both Ventricles the one manifestly preceding the pulse of the other which two motions the bare eye judges to be Synchronical and without any interloping perisystole at all So admirable is every Organ of this Machine of ours framed that every part within us is intirely made when the whole Organ seems too little to have any parts at all Thirdly It is peculiarly remarkable from Observation xxxi That not onely the bloud in perfect Animals and the chyle in imperfect ones but also the Animal Spirits have a Circulation which singular observation hath often provoked and entised our endeavours into a further enquiry after the Nature of these Spirits as to their Origin or Generation their activity and motion with some other eminent properties belonging to them we shall draw our thoughts together and so present them to your View I will not say that our discourse hereon shall pass for an un-controllable authentick Truth it is all my ambition if it attain but to the favourable reception of a rational Hypothesis at last A Digression of the Animal Spirits FIrst then we have not those narrow conceptions of these subtle Spirits to think that they are onely included within the Bodies of Animals or generated much less created there but we doe believe that they are universally diffused throughout all Bodies in the World and that Nature at first created this aetherial substance or subtle particles and diffused them throughout the Universe to give fermentation and concretion to Minerals vegetation and maturation to Plants life sense and motion to Animals And indeed to be the main though invisible Agent in all Natures three Kingdoms Mineral Vegetal and Animal And lest they should because of their exceeding volatility and activity be of little or no use Nature hath immersed them in grosser matter and imprisoned them in several Bodies with which she has intermixed them the better to curb the boundless activity of so thin and spirituous a substance and therefore the Spirits of all compound Bodies especially ought to be considered under a triple notion Viz. Under the state of 1. Fixation 2. Fusion 3. Volatilization First of Fixation when they are so complicated with the grosser Particles of Matter and lockt therein so fast that they can hardly be separated and dis-imprisoned as in Minerals but most especially in Gold Secondly The state of Fusion I call that when the Spirits by any kind of help have so wrought themselves towards a Liberty that they are in the middle way to Volatility as in half-concocted Minerals fermenting Vapours or Liquors and half-ripned Fruits c. Thirdly The Spirits are in their third state of Volatility when after a colluctancy with the grosser Particles they have so subjugated and overcome them that they are just upon wings and ready to fly away as in Wine when it is in the height of its fermentation and in some part of our arterial bloud alwayes Now we observe that those Bodies that relax and open the grosser composition of other Bodies do presently create a fermentation for being like so many Keys they set the imprisoned Spirits at Liberty which presently fall on working and by attenuating the grosser parts separating the Heterogeneous volatilizing some precipitating of others digesting of others expelling of others do at last mould it and work it to such a Body as the parts of it are fit to make up In all which interval of time there is a palpable and sensible heat produced Thus this Spirit being embowelled in the Earth and meeting there with convenient matter and adjuvant causes doth proceed to produce Minerals creating an actual heat wheresoever it operates as in Allum or Copperase Mines which being broken exposed and moistned will gather an actual heat and produce much more of those Minerals then else the Mine would yield as Agricola and Thurniseer do affirm and is proved by common experience The like is generally observed in Mines as Agricola Erastus and â—ibanius c. do affirm and avouch out of the dayly experience of Mineral men who affirm that in most places they find their Mines so hot as they can hardly touch them although it is likely that where they work for perfect Minerals the heat which was in fermentation whilst they were yet in breeding is now much abated the Mineral being grown to their perfection as the skilful and excellent Doctor Jordan very well infers The like heat we observe constantly to be in our Cole-Pits Nay we sometimes observe in our Brass-lumps as our Colliers call them which is a kind of Marcasite a very great heat for being exposed to the moist Air or sprinkled with water they will smoak and grow exceeding hot and if they be layd up on a heap and watered they will turn into a glowing red hot fire as I have seen them my self And it was a Casualty once terrible to our Neighbour-Town of Ealand for there one Wilson a Patient
he then vomits into a Vineger-glass again and that presents white Wine At the next disgorgement when his stomack is full of nothing but clear water indeed which he has fill'd so by the exceeding quantity of water which at every interval he drinks he then deludes the Spectators by vomiting Rose water Angelica water and Cinamon water into those glasses which have been formerly washed with those Spirits And thus was that famous Cheat perform'd and indeed acted with such a port and flowing grace by that Italian Bravado that he did not onely strike an Admiration into vulgar heads and common Spectators but even into the judicious and more knowing part of men who could not readily find out the ingenuity of his knavery The Chymical Elaboratories likewise do teach us this Truth in Fumes and Smoaks as well as Liquors which indeed are but rarified and expaused Liquors for Niter it self though nothing a kin to redness doth in distillation yield bloud-red Fumes called by the Chymists Salamanders-bloud which fall again into a Liquor which hath nothing of red in it So Soot though black yet when it is pressed and forced up into an exhalation by a strong fire will fill the Receiver with Milk white Fumes thus Sall-Armoniack and black Antimony being equally mixed and gradually sublimed in an Urinal will exhibit a Scene of Colours and will make a transition out of one into another with a delectable variety By all which pleasant Observations it palpably appears that the nature of Colours consists in the free admission transition refraction or reflection of light from the Objects discoloured For first you see several Colours introduced into Liquors by those Ingredients that neither had nor could communicate any such tincture Secondly 't is as plain that the minute Particles and Atoms of those Bodies that were imbibed by the Liquors and filled up their smallest Cavities or Interstices accordingly as they were altered in their site position and motion so were the Luminous Beams variously transmitted refracted or reflected and so consequently thence resulted those several Scenes of Colours Thus when the Atoms wherewith the Liquor is fully impregnated do relax and open themselves that the light may fairly penetrate then is the Liquor limpid and clear but if they draw up a little closer one to another so that the light be refracted then is the Liquor yellow if closer yet to a greater refraction of the Light then is the Liquor red but if in this randezvouz they draw up into a very close Body indeed so that by reason of their contiguity both in rank and file no light can be trajected through them then opacity and darkness arises If the Rays cannot break the front of them then is a milky-Whiteness presented there The Fifth COROLLARY Anatomical Considerations about the Eye OUr next Reflections shall be made upon the Eye to admire as well as contemplate Nature's variety in the constructure and conformation of so excellent an Organ The two Luminaries of our Microcosm which see all other things cannot see themselves nor discover the excellencies of their own Fabrick Nature that excellent Mistress of the Opticks seems to have run through all the Conick Sections in shaping and figuring its Parts and Dioptrical Artists have almost ground both their Brain and Tools in pieces to find out the Arches and Convexities of its prime parts and are yet at a loss to find their true Figurations whereby to advance the Fabrick of their Telescopes and Microscopes which practical part of Opticks is but yet in the rise but if it run on as successfully as it has begun our Posterity may come by Glasses to out-see the Sun and Discover Bodies in the remote Universe that lie in Vortexes beyond the reach of the great Luminary At present let us be content with what our Microscope demonstrates and the former Observations I am sure will give all ingenious persons great occasion both to admire Nature's Anomaly in the Fabrick as well as in the number of Eyes which she has given to several Animals We see the Tunica Cornea in most Insects is full of perforations as if it were a Tunica Vvea pinked full of Holes and whereas perfect Animals have but one Aperture these Insects have a thousand Pupils and so see a Hemisphere at once and indeed 't is worth our consideration to think that since their Eye is perfectly fixed and can move no wayes it was requisite to lattice that Window and supply the defect of its Motion with the multiplicity of its Apertures that so they might see at once what we can but do at several times our Eyes having the liberty and advantage to move every way like Balls in Sockets which theirs have not Secondly We observe no diaphanous parts in those lattic'd Eyes since it is probable that the Horney Coat of the Eye serves also for a Pericranium for their Brain For that the Brain of most Insects lies in their Eyes seems to me more than a probability First because in Flies Butter-flies Bees c. you can find no other place in their Heads wherein any matter analogous to the Brain can be lodged Secondly in the Eyes of those Insects you shall alwayes find great store of a pulpous substance like to be Brain in those Creatures Thirdly the Eyes in all Insects are very large and seem disproportional to so small Bodies if intended for no other use than Vision Fourthly why may not this lattic'd film of their Eye be their Tunica Retina which as it is concave in us is convex in them and as it is made of the Brain in us so it is in them and therefore lies contiguous to it and may indeed be over-cast by a transparent Cornea through which the Net-work of this interiour film may thus eminently appear For certainly such Animals as have distinction of Senses as Seeing Feeling c. must needs have an Animal-Sensation an Animal I say for I hold also a natural Sensation which is performed without a Brain and such an one is discoverable even in Animals and in our own Selves for besides the Animal-Sensation whose original is in the Brain the Stomach Guts and the Parenchymata of the Body yea and the Bloud too has a natural Sensation of what is good and what is bad for them as Doctour Harvey has excellently proved Lib. de Gener. and so some of the lowest rank of Animals as the Zoophyta and plant-Animals may perchance be utterly devoid of Animal and have onely a Natural Sensation but this belongeth to some Anatomical Observations I have by me where I may perchance prove that all Vegetables as well as the Sensitive and humble Plants have this latter kind of Sensation as well as Animals But let us return to the Eye again of which curious Organ I am tempted to say much more but that I have reserved that discourse as more proper for my Telescopical Observations Onely for the present to encourage the Lovers of free Philosophy and to let
partly arise from the variations of the Climates the Air being more thin and hot then ours partly from the difference and altitude of the Atmosphere here and there as shall hereafter be made more intelligible and partly from the diversity of our measures and theirs or from the club and combination of all these causes joyned together To which I may well super-add the negligence or inconsideration of those that try this Experiment for you may alter the height of the Mercurial Cylinder as you do rudely or cautiously tunnel in the Quicksilver into the Tube for I have some time with exact caution made it to rise to 30. inches in altitude from the Surface of the restagnant Quicksilver in the Vessel I set down 29. inches as its determinate height to which it will for the most mount though you use but a careless kind of carefulness in the management of the Experiment CHAP. II. That in the superiour part of the Tube there is no absolute Vacuity BEfore we proceed to any further Experiments we will first canvass the Cause of this Primitive one of Torricellius which has given occasion of trying all the rest and then we wilâ— deliver our Hypothesis which I hope will salve all the strange appearances not onely in this but in those stranger that follow Valerianus Magnus and some others are so fond to believe this deserted Cylinder to be an absolute Vacuity which is not only non-philosophical but very ridiculous 1. For the Space deserted hath both Longitude Latitude and Profundity therefore a Body for the very nature of a Body consists onely in extension which is the essential and unseparable property of all Bodies whatsoever 2. Again we have the sensible eviction of our own eyes to confute this Suppositional Vacuity for we see the whole Space to be Luminous as by Obser. Now Light must either be a Substance or else how should it subsist if a bare Quality in a Vacuity where there is nothing to support it 3. Again the Magnetical Efluxions of the Earth are diffused through that seeming Vacuity as per Experiment 4. There is some Air also interspersed in that seeming Vacuity which cannot be expelled upon any inclination of the Tube whatsoever as by Obser. is manifest 5. The most full Evidence against this pretended Vacuity is from the returgenscency of the empty Bladder suspended in this Vacuity for how should it be so full blown from nothing as is by Exp. most incomparably evinced CHAP. III. That it is not the Efluviums of Mercury that fill up that seeming Vacuity BEfore we come positively to declare what it is that supplies this seeming Vacuity let us draw some negative Conclusions and see if we can prove that it is not supplied with any Spirits Mercurial or Exhalations and this we shall most fully do by an ingenious Experiment borrowed from the Mechanical Wit of Doctor Pascal which shall passe for the second in the Bedroll of our Experiments Doctor Pascal's Experiment 2. THat the deserted part of the Tube is not filled up with any Hydrargyral emanations may be thus evinced because he hath found the same Experiment to succeed in water onely without any Quicksilver at all for he took a Tube or Lead-Pipe of 46. foot in length made close at the one end in casting of it and having filled it full of water and reversed it into a paile of water underneath about a foot deep he found the water to fall within 32. foot of that in the Vessel so that the deserted part of the Pipe was 13. foot so tall a Cylinder of that Liquor being it seems but aequi-ponderous to a Mercurial Cylinder of 28. inches Kircher and Birthius it seems also have tried the like in a Lead-Pipe of a 100. foot long and an inch diameter into which at the top was let in a short neck'd weather-glass or bolt-head and fastned so to that no Air could pierce the coement that luted the Glass and Lead-Pipe together which Lead-Pipe at the bottome was also fitted with a Turn-cock which when it was once filled with water would keep it in till they had reversed it into a Hogshead of water underneath and then by a turn of the Cock letting out the water it deserted the Bolt head and superiour part of the Tube wherein appeared this seeming Vacuity Experiment 3. BUt for a further Confirmation of this Truth let me subjoyn another Experiment which shall here pass for our third of the same Author 's Take a Glass-Syringe or Squirt of what length you please exactly fitted with a Squirt-staff stop the mouth of your Syringe close with your finger and so drown it over head and ears with hand and all in a large Vessel of water then draw back the Squirt staff and the Syringe will appear a Vacuity which will pain your finger by an Introsuction of it in at the Orifice but if then you erect the Syringe perpendicular and draw it all out of the water excepting that end closed by your finger and then open the Orifice you shall see the water suddainly arise and fill the deserted Cavity of the Syringe Both which Experiments do sufficiently prove that this seeming Vacuity may be exhibited without the help of any Quicksilver at all and therefore this imaginary Space in the Torricellian-Experiment aforesaid cannot rationally be supposed to be repleated with any Mercurial Effluviums CHAP. IV. Experiment 4. That it is not Light onely which supplies this seeming Vacuity TAke the Barrel of a long Gun about 4. foot long and Bunging up the Touch-Hole fill it easily with Mercury and reversing of it into the Vessel'd Quicksilver as before you may measure it to observe the determinate height aforesaid which you may easily perceive First By the flushing out of the Quicksilver upon removal of your finger into the Vessel where the restagnant Quicksilver receives it Secondly By the re-ascent of the Quicksilver upon tilting or plucking the Gun quite out of the restagnant Mercury as also by the forceable introsuction of your finger if you close the muzzle of the Barrel within the Vessel'd Mercury and so draw it out and reverse it as also by the plucks and shogs it will give in that action Thirdly and most perceptibly By the repletion of it with water if you draw the Tube gently out of the Quicksilver in the Vessel into a super-incumbent region of water which you first poured into the same Vessel for then if you stop the Orifice with your finger whilst it stands immers'd in the region of water and so draw it out and reverse it you shall perceive it full of water The like no doubt will succeed in Tubes of other Mettals Again if Light onely onely I say because we do not deny light to be there fill up that empty Cylinder it would be certainly far more Luminous as containing nothing but the pure Solary Atoms than the external medium and region of the Air about it which is confusedly intermixed both with