Philosophical Transactions of the Royal Society Part 7

First therefore, after that M _Auzout_ had raised some scruple against the Contrivance of Signor _Campani_ for making _Great Optick-Gla.s.ses_ without _Moulds_, by the means of a _Turn-lath_, he examines the _Observations_, made with such _Gla.s.ses_: Where, having commended _Campani_'s sincerity in relating what he thought to have seen in _Saturn_, without accomodating it to M. _Hugens_'s _Hypothesis_, he affirms, that supposing, there be a _Ring_ about _Saturn_, Signor _Campani_ could not see in all those different times, that he observed it, _the same Appearances_, which he notes to have _actually_ seen. For, having seen it sometimes in _Trine Aspect_ with the _Sun_, and _Oriental_; sometimes, in the same _Aspect_, but _Occidental_; sometimes in _s.e.xtil Aspect_, and _Occidental_; at another time, again in _Trine_, and _Oriental_, this Author cannot conceive, how _Saturn_ could in all these different times have no difference in its _Phasis_, or keep always the same _Shadow_; seeing that, according to the _Hypothesis_ of the _Ring_, when it was _Oriental_, it must cast the _Shadow_ upon the _left_ side of the _Ring_ beneath, without casting any on the _right_ side: and when it was _Occidental_, it could not but cast it on the _right_ side beneath, and nothing of it on the other.

Concerning the _Shadow above_, which _Campani_ affirms to be made by the _Ring_ upon the Body of _Saturn_, M. _Auzout_ judges, that there could be no such _Phaenomenon_, by reason of its _Northern Lat.i.tude_ at the times, wherein the _Observations_ were made, _vid._ in _April_ 1663; in the midst of _August_, and the beginning of _October_, next following, and in _April_ 1664, except it were in _October_, and the _Shadow_ strong enough to become _visible_.

But as to the _Shadow below_, he agrees with _Campani_, that it does appear, yet not as he notes it, seeing that it must be sometimes on the one side, sometimes on the other; and towards the _Quadrat_ with the _Sun_ it must appear biggest, as _indeed_ he affirms to have seen it himself _this_ year, insomuch that sometimes it seemed to him, that it covered the whole _Ring_, and that the _Shadow_, joyning with the obscure s.p.a.ce between both, did interrupt the circ.u.mference of the _Ring_; but beholding it at other times in a cleer Sky, and when there was no Trepidation of the Air, {72} he thought, that he saw also the Light continued from without, although very slender. But he acknowledges, that he could never yet _precisely_ determine, by how much the largeness of the _Ring_ was bigger than the _Diameter_ of _Saturn's_ Body. As for the proportion of the Length to the Breadth, he affirms, to have alwaies estimated it to be two and a half, or very neer so; and to have found in his _Observations_, that in _January_ last, one time, the length of _Saturn_ was 12 _Lines_, and the breadth 5.

Another time, the length was 12. _Lines_, and the breadth 4. and this by a peculiar method of his own. But yet he acknowleges also, that sometimes he hath estimated it as 7. to 3. and at other times as 13. to 5. and that if there do not happen a change in the magnitude of the _Ring_ (as it is not likely there does) that must needs proceed from the Const.i.tution of the air, or of the Gla.s.s's having more or less _Aperture_, or from the difficulty of making an exact estimate of their proportions. However it is not much wide (saith he) of two and a half, although _Campani_ make the length of the _Ring_ but double to its breadth.

Monsieur _Auzout_ believes, that he was one of the first that have well observed this shadow of _Saturn's_ Body upon its _Rings_ which he affirms happened two years since; when, observing in _July_, for the first time, with a _Telescope_ of 21. and then another of 27. foot, he perceived, that the _Angle_ of the obscure s.p.a.ce on the _right side_ beneath, was bigger and wider, than the three other _Angles_, and that some interruption appear'd _there_, between the _Ring_, and the _Body of Saturn_; of which he saith to have given notice from that time to all his friends, and in particular, as soon as conveniently he could, to Monsieur _Hugens_.

He confesseth, that he hath not had the opportunity of observing _Saturn_ in his _Oriental Quadrat_; yet he doubts not, but that the _shadow_ appears on the _Left-side_, considering, that the _Existence_ of the _Ring_ can be no longer doubted of, after so many _Observations_ of the _shadow_ cast by _Saturn's_ Body upon it, according as it must happen, following that _Hypothesis_; there being no reason, why it should cast the said _shadow_ on one side, and not on the other.

Concerning the Observation of _Jupiter_ and its _satellites_, the famous _Astronomer_ of _Bononia_, _Ca.s.sinus_, having {73} published, that on the 30. day of _July_, 1664. at 2 of the clock in the morning, he had observ'd, with _Campani_'s Gla.s.ses, that there pa.s.sed through the broad obscure _Belt_ of _Jupiter_ two obscurer _spots_, by him esteemed to be the _shadows_ of the _Satellites_, moving between _Jupiter_ & the _Sun_, and eclipsing him, and emerging from the Occidental Brim thereof: This _Authour_ did first conceive, that they were not _shadows_, but some _Sallies_, or _Prominencies_ in that _Belt_; which he was induced to believe, because he perceived not, that that _Prominency_, which he there saw, was so black, nor so round as _Ca.s.sini_ had represented his _spots_; wherefore, seeing it but little differing in colour, from the _Belt_, and so not judging it round, because it did stand only about half its diameter out of the _Belt_, he persuaded himself, that it was rather a _Sally_, or _Prominency_ of the _Belt_, than a round _shadow_, as that of a _Satellite_ of _Jupiter_ must have bin. But having been since informed of _all_ the _Observations_ made by _Ca.s.sini_ and _Campani_, with the _New_ Gla.s.ses, and seen his _Figure_, he candidly and publickly wisheth, that he had not spoken of that _Sally_, or _Prominency_; advowing that he can doubt no longer, but that it was the _shadow_ of the _Satellit_ between _Jupiter_ and the _Sun_, having seen the other emerge, as soon as with a 20. foot Gla.s.s he made the Observation, and having not perceiv'd these _shadows_ with a 12. foot Gla.s.s: But although he grants that they did ghess better than he, yet he doth it with this _proviso_, _vid._ in case they made _that_ Observation on of _July_ 30. not with their 36. but 12. or 17. foot _Telescope_. If it be wondred at, that Monsieur _Auzout_ did not see this _shadow_ move, he allegeth his indisposition for making _long Observations_, and addeth, that it may be much more wondred at, that neither _Campani_ nor himself did see upon the obscure _Belt_ the Bodies of the _Satellites_, as parts more Luminous than the _Belt_. For (saith he) although the _Lat.i.tude_ was _Meridional_, it being no more than of 9. or 10. minutes, the Body of the _Satellites_ should, thinks he, pa.s.s between _us_ and the _Belt_, especially according to _Campani_, who maketh the _Belt_ so large, and puts the _shadows_ farr enough within the same. This maketh him conclude, that either they have not observed well enough, or that the motion of the _Satellites_ doth not exactly follow the _Belts_, and is inclin'd unto them. Whereupon he resolves, that when he shall know that they are to pa.s.s between _Jupiter_ and _us_, and to be over against the _Belt_, that {74} then he will observe, whether he can see them appear upon the _Belt_, as upon a darker ground, especially, the _third_ of them, which is sensibly greater, and more Luminous, than the rest. He hopeth also, that in time, the _shadow_ of _Saturns Moon_ will be seen upon _Saturn_, although we are yet some years to stay for it, and to prepare also for better Gla.s.ses.

From this rare Observation, he inferrs the _Proportion_ of the _Diameter_ of the _Satellites_ to that of _Jupiter_; and judgeth, that no longer doubt can be made of the turning of these 4. _Satellites_, or _Moons_ about _Jupiter_, as our _Moon_ turns about the _Earth_, and after the same way as the rest of the Celestial Bodies of our _Systeme_ do move: whence also a strong conjecture may be made, that _Saturns_ Moon turns likewise about _Saturn_.

Hence he also taketh occasion to intimate, that we need not scruple to conclude, that if these two _Planets_ have _Moons_ wheeling about them, as our _Earth_ hath one that moves about it, the conformity of these _Moons_ with our _Moon_, does prove the conformity of our _Earth_ with those _Planets_, which carrying away their _Moons_ with themselves, do turn about the _Sun_, and very probably make their _Moons_ turn about them in turning themselves about their _Axis_; and also, that there is no cause to invent perplex'd and incredible _Hypotheses_, for the receding from this _a.n.a.logie_ since (saith he) if this be truth, the Prohibitions of publishing this doctrine, which formerly were caused by the offence of Novelty, will be laid aside, as one of the most zealous Doctors of the contrary Opinion hath given cause to hope, witness _Eustachius de Divinis_, in his _Tract_ against Monsieur _Hugen_'s _Systeme_ of _Saturn_, _p._ 49.

where we are inform'd, that that learned Jesuit, _P. Fabry_, Penitentiary of S _Peter_ in _Rome_, speaks to this purpose:

Ex vestris, iisque Coryphaeis non semel quaesitum est, utrum aliquam haberent demonstrationem pro _Terrae motu_ adstruendo. Nunquam ausi sunt id a.s.serere Nul igitur obstat quin loca illa in sensu literali Ecclesia intelligat, & intelligenda esse declaret, quamdiu nulla demonstratione contrarium evincitur; quae si forte aliquando a vobis excogitetur (quod vix crediderim) in hoc casu nullo modo dubitabit Ecclesia declarare, loca illa in sensu figurato & improprio intelligenda esse, ut illud Poetae, _Terraeque Urbesque recedunt_.

_It hath been more than once asked of your Chieftains, whether they had a Demonstration for a.s.serting the motion of the Earth? They durst never yet affirm they had; wherefore nothing hinders, but that the Church may understand those Scripture-places, that speak of this matter, in a _literal_ sence, and declare they should be so understood, as long as the contrary is not evinced by any demonstration; {75} which, if perhaps it should be found out by you (which I can hardly believe it wil) in this case the Church will not at all scruple to declare, that these places are to be understood in a figurative and improper sence, according to that of the Poet, _Terraeque Urbesque recedunt_._

Whence this Author concludes, that the said _Jesuite_ a.s.suring us that the _inquisition_ hath not _absolutely_ declared, that those Scripture-places are to be understood _literally_, seeing that the _Church_ may make a contrary declaration, no man ought to scruple to follow the _Hypothesis_ of the _Earths motion_, but only forbear to maintain it in _publick_, till the prohibition be called in. But to return to the matter in hand, this Author, upon all these observations and relations of _Ca.s.sini_ and _Campani_, doth find no reason to doubt any more of the excellency of the Gla.s.s used by them, above his; except this difference may be imputed to that of the _Air_, or of the _Eys_. But yet he is rather inclined to ascribe it to the goodness of their Gla.s.ses, and that the rather, because, he would not be thought to have the vanity of magnifying his own; of which, yet he intimates by the by, that he caused one to be wrought, of 150 _Parisian_ feet; which though it proved none of the best, yet he despairs not to make good ones of _that_, and of far greater Length.

__Signor Campani's_ Answer: and Monsieur _Auzout_'s Animadversions thereon._

The other part of this _French Tract_, conteining _Campani_'s Answer, and Mr. _Auzout_ his _Reflections_ thereon, begins with the pretended _Shadows_ of the _Ring_ upon _Saturn_, and of _Saturn_ upon the _Ring_. Concerning which, the said _Campani_ declareth, that he never believed them to be _shadows_, made by the _Ring_ upon the _Disk_ of _Saturn_, or by the body of _Saturn_ upon the _Ring_, but the _Rimms_ of these bodies, which being _unequally_ Luminous, did shew these appearances. In which Explication, forasmuch as it represents, that the said _Campani_ meant to note only the _Inequality of the Light_, which, _he saith_, his Gla.s.ses did discover, Mr.

_Auzout_ does {76} so far acquiesce, that he only wishes, that his own Gla.s.ses would shew him those differences. Next to the Objection, made by Monsieur _Auzout_, against Signor _Campani_, touching the Proportion of the Length of the _Ring_ to its breadth, _Campani_ replyeth, that the Gla.s.ses of Monsieur _Auzout_, shew not all the particulars, that his do, and therefore are unfit for determining the true Figure and breadth of the apparent _Ellipsis_ of the _Ring_. To which M. _Auzout_ rejoyns, that he is displeased at his being dest.i.tute of better Gla.s.ses, but that it will be very hard for the future to convince _Campani_ touching the _Proportion_ of the _Ring_, seing that the breadth of the _Ellipsis_ is always diminishing, although, if the declination of the _Ring_ remains always the same, one can at all times know, which may have been its greatest breadth. But he a.s.sures, that the breadth of the _Ring_ is not the half of its length, and that it doth not spread out so much beyond _Saturn_'s Body, as he hath alleged. And withal desirs to know, what can be answered by Sig. _Campani_ to M. _Hugens_, who being persuaded, that the Declination of the _Ring_ is not above 23 deg. 30' having seen the _Ring_ to spread out above the Body of _Saturn_, concludes, in a Letter to M. _Auzout_, that the length of the _Ring_ is more than treble the _Diameter_ of _Saturn_'s body, which, according to _Campani_, is only as about 67 to 31. Which difference yet dos not appear to M. _Auzout_ to be so great; but that M. _Hugens_ perhaps will impute it to the Optical reason, which he (_Auzout_) hath alleged of the Advance of the light upon the obscure s.p.a.ce; although he is of Opinion, he should not have concluded so great a Length, if he had not seen the Breadth spread out more, than he hath done: for (_saith he_) if the Length of the _Ring_ be to the body of _Saturn_, 2 to 1. and the _Inclination_ be 23 deg. 30' the _Ring_ will be just as large, as the body, without spreading out; but if the _Ring_ be bigger, it will a little spread out; and if it were treble, it must needs spread out the half of its breadth, which hath not so appeared to him.

Further, to M. _Auzout's_ change of Opinion, and believing, that the _Advance_ or _Sally_, seen by him in _Jupiter_, was the _Shadow_ of one of his Moons, _Campani_ declares, that he would not have him guilty of that change: Whereupon M. _Auzout_ wonders, why _Campani_ then hath not marked it in his _Figure_; and would {77} gladly know, whether that _Sally_ be more easie to discover, than the _Shadows_ of the _Satellites_, which _Campani_ believs, _Auzout_ hath not seen; and whether he be a.s.sured, that those obscure parts, which he there distinguishes, do not change: for if they should not change, then _Jupiter_ would not turn about his _Axis_, which yet, he saith, it doth, according to the _Observation_ made by Mr.

_Hook_, _May_ 9 1664. inserted in the first papers of these _Transactions_.

The full Discovery of which particular also he makes to be a part of _Ca.s.sini's_ and _Campani_'s work, seeing that they so distinctly see the inequalities in the _Belts_, and see also sometimes other _Spots_ besides the _Shadows_ of the _Satellites_: where he exhorts all the Curious, that have the conveniency of observing, to endeavor the discovery of a matter of that importance, which would prove one of the greatest _a.n.a.logies_ for the _Earth's Motion_.

_An Account of Mr. _Richard Lower_'s newly published _Vindication_ of Doctor _Willis_'s _Diatriba_ de _Febribus_._

The t.i.tle of this Curious piece, is _Diatribae Thomae Willisii Med. Doct. & Profess. Oxon. De Febribus Vindicatio, Auth.o.r.e Richardo Lower, &c._ In it are occasionally discussed many considerable Medical and Anatomical inquiries, as, Whether a Fever does consist in an Effervescence of Blood?

And if so, of what kind? Whether there be a _Nervous_ and _Nutritious_ Juice? Whether the office of sanguification belongs to the Blood it self, existing _before_ those _Viscera_ (at least) that are commonly esteemed to be the Organs of sanguification? How _Nutrition_ is performed, and the nourishing substance a.s.similated? Whether the Blood affords both the Matter for the structure of the Body, and such parts also, as are fit for the nourishment of the same? Whether the Pulse of the Heart ceasing, there remains yet a certain Motion in the blood, arguing, that _Pulse_ and _Life_ do ultimately rest in the _Blood_? Whether the Umbilical Vessels convey the blood of the Mother to the Child, or whether the _Foetus_ be for the most part form'd and {78} acted by the circulating blood, before the existence of the Umbilical Vessels, or before the connecting of the _Foetus_ with the _Uterus_? A new Experiment to prove that the _Chyle_ is not trans.m.u.ted into _Blood_ by the _Liver_. A discourse of the Nature of the _Blood_, and what difference there is between the _Venal_ and _Arterial_ blood, and for what Uses both the one and the other are particularly designed. Where it is considered, what _Life_ is, and whence the _Soul_ of _Brutes_, and its subsistence, and operations do depend. It is also inquired into, what the uses of the _Lungs_ are in _hot_ Animals? And many other such material disquisitions are to be found in this small, but very Ingenious and Learned Treatise.

_A Note touching a Relation, inserted in the last _Transactions_._

In the Experiment of killing _Ratle-Snakes_, mentioned in the last of the precedent Papers (wherein, by a mistake, these words, _The way_, were put for _A way_, or _An Experiment_) it should have been added, that the Gentleman there mention'd, did affirm, that, in those places, where the Wild _Penny-Royal_ or _Dittany_ grows, no _Ratle-Snakes_ are observed to come.

_Errata._

Pag. 59. line 11. read, _bignesses_, l. 20. r. _endure_, for, resist. l.

30. r. _those_, for, these. l. 31. r. _Plain_, for, place.

_LONDON,_

Printed with Licence, By _John Martyn_, and _James Allestry_, Printers to the _Royal-Society_, at the _Bell_ in St. _Pauls Church-Yard_. 1665.

{79}

_Numb._ 5.

PHILOSOPHICAL _TRANSACTIONS._

_Munday_, _July_ 3. 1665.

The Contents.

_An Account, how _Adits_ and _Mines_ are wrought at _Liege_ without _Air-shafts_, communicated by Sir _Robert Moray_. A way to break _easily_ and _speedily_ the hardest _Rocks_; imparted by the same _Person_, as he received it from Monsieur _Du Son_ the Inventor.

Observables upon a _Monstrous Head_. Observables in the Body of the Earl of _Belcarres_, sent out of _Scotland_. A Relation of the designed Progress to be made in the _Breeding of Silk-worms_, and the _Making_ of _Silk_, in _France_. Enquiries touching _Agriculture_, for _Arable_ and _Meadows_._

_An Account, how _Adits_ & _Mines_ are wrought at _Liege_ without _Air-shafts_, communicated by Sir _Robert Moray_._

It is well known to those conversant in _Mines_, that there is nothing of greater inconvenience in the working or _driving_, as they call it, of _Mines_ or _Adits_ under ground, for carrying away of Water, or such _Minerals_ as the _Mine_ affords, than the _Damp, want,_ and _impurity of Air,_ that {80} occur, when such _Adits_ are wrought or driven inward upon a _Level_, or near it, 20, 30, or 40. fathom, more or less. Aswel because of the expence of money, as of time also, in the _Ordinary_ way of preventing or remedying those inconveniences; which is, by letting down _shafts_ from the _day_ (as _Miners_ speak) to meet with the _Adit_; by which means the Air hath liberty to play through the whole work, and so takes away bad vapours and furnishes good Air for Respiration. The Expence of which _shafts_, in regard of their vast depth, hardness of the Rock, drawing of water, &c. doth sometimes equal, yea exceed the _ordinary_ charge of the whole _Adit_.

Amongst the _Expedients_ that have been devised to remedy this, there is one practised in the _Coal-mines_, near the Town of _Liege_ (or _Luyck_) that seems preferable to all others for Efficacy, Ease, and Cheapness: the description whereof followeth.

At the mouth or entry of the _Adit_ there is a structure raised of _Brick_, like a _Chimney_, some 28. or 30. foot high in all: at the bottom, two opposite sides are (or may be) some 5 foot broad; and the other two, 5.

foot: the wall 1 _Brick_ thick. At the lower part of it, is a hole, some 9. or 10. inches square, for taking out of the Ashes, which when it is done, this Ash-hole is immediately stopt so close, as Air cannot possibly get in at any part of it. Then, some 3. foot above ground or more, there is on that side, that is next to the _Adit_ or Pit, a square hole of 8. or 9.

inches every way, by which the Air enters to make the Fire burn: Into this hole there is fixed a square _Tube_ or _Pipe_ of Wood, whereof the Joints and c.h.i.n.ks are so stopt with Parchment pasted or glewed upon them, that the Air can no where get in to the Pipe but at the end: And this Pipe is still lengthened, as the _Adit_ or Pit advanceth, by fitting the new Pipes so, as one end is alwaies thrust into the other, and the Joints and c.h.i.n.ks still carefully cemented and stopt as before. So the Pipe or Tube being still carried on, as near as is necessary, to the wall or place, where fresh Air is requisite; the Fire within the Chimney doth still attract {81} (so to speak) Air through the Tube, without which it cannot burn, which yet it will do, as is obvious to conceive (all Ill.u.s.trations and Philosophical Explications being here superfluous,) and so, while the Air is drawn by the fire from the farthest or most inward part of the _Mine_ or _Adit_, fresh Air must needs come in from without to supply the place of the other, which by its motion doth carry away with it all the ill vapors, that breath out of the ground; by which meanes the whole _Adit_ will be alwaies filled with fresh Air, so that men will there breath as surely as abroad, and not only Candles burn, but Fire, when upon occasion there is use for it for breaking of the Rock.

Now that there may be no want of such fresh Air, the Fire must alwaies be kept burning in the Chimney, or at least as frequently as is necessary: For which purpose there must be two of the Iron Grates or Chimneys, that when any accident befals the one, the other may be ready to be in its place, the Coals being first well kindled in it: but when the fire is neer spent, the Chimney or Grate being haled up to the dore, is to be supplied with fresh fuel.