Chapter 36

_An Account, formerly promised, of Monsieur _Hevelius's_ Calculation of the late _Solar Eclipse's_ Quantity, Duration, &c. The Figure of the Star in the Constellation of _Cygnus_, together with the New Star in it, discovered some years ago, and very lately seen again by the same Mr. _Hevelius_. An Extract of a Letter, written by Mr. _Auzout_, concerning a way of his, for taking the _Diameters_ of the Planets, and for knowing the _Parallax_ of the _Moon_: Giving also a Reason, why in the _Solar Eclipse_ above-mentioned, the _Diameter_ of the _Moon_ did increase about the end. A Relation of the loss of the Way to prepare the _Bononian Stone_ for shining. A Description of a _Swedish Stone_, affording _Sulphur, Vitriol, Allum_, and _Minium_. A Relation of the Raining of Ashes. An Extract of a Letter from _Rome_, rectifying the Relation of _Salamanders_ living in Fire. An Account of several Engagements for _Observing of Tydes_. Some Suggestions for Remedies against Cold. A Relation of an uncommon accident in two Aged Persons. An Account of Two Books, _I. ISMAELIS BULLIALDI ad Astronomos Monita duo: Primum, de Stella Nova, in _Collo Ceti_ ante aliquot annos visa. Alterum, de Nebulosa Stella in _Andromedæ_ Cinguli parte _Borea_, ante biennium iterum ortâ. II. ENTRETIENS sur les vies & sur les Ouvrages des plus excellens Peintres, antients & modernes, par M. FELIBIEN_._

* * * * *

_Monsieur _Hevelius_'s Calculation of the late _Solar Eclipse's_ Quantity, Duration, &c._

This _Calculus_ was not long since communicated by Monsieur _Hevelius_ in a Letter to the _Publisher_, as follows, {370}

_Eclipsis Solaris._

_Observata An. 1666. D. 2. Julii, St. N. Mane, à Johanne Hevelio._

----+-----------------+-----------+----------+--------+--------+---- Ordo| |Temp æstin | |Altitude| | Pha-|Quantitas |sec. horol |Temp. sec.| [Sun] |Tempus | sium|Phasium |ambulat. |Sciother. | |correct.|Anim. ----+-----------------+-----------+----------+--------+--------+---- | |H. ' " |H. ' " | °. ' |H. ' " | | |5.51.11 |5.51. 0 |17.45 |5.53.12 | 1. | |5.57. 5 |5.57. 0 |18.37 |5.59.28 | | |6. 0. 0 |6. 0. 0 |18.55 |6. 1.28 | ----+-----------------+-----------+----------+--------+--------+---- |Initium |6.55.30 | | |6.57.30 | 2. 1 |0-3/8 dig. |6.57.30 | | |5.59.30 | 2 |0-3/4 |7. 0.23 |7. 0. 0 | |7. 2.23 | 3 |1-1/8 |7. 2.30 |7. 2. 0 | |7. 4.30 | ----+-----------------+-----------+----------+--------+--------+---- 4 |1-1/2 dig. |7. 4.50 |7. 5 ferè.| |7. 6.50 | 5 |1-3/8 ferè. |7.10.57 |7.10 | |7.12.57 | 6 |3-3/8 |7.14.59 |7.15 | |7.16.59 | 7 |3-3/4 |7.17.50 |7.18 ferè.| |7.19.50 | ----+-----------------+-----------+----------+--------+--------+---- 8 |4-3/8 dig. |7.21.35 |7.21 | |7.23.35 | 9 |4-2/3 |7.23.43 |7.23 ferè.| |7.25.43 | 10 |5-1/4 |7.27.53 |7.28 | |7.29.53 | 3. 11 |6 |7.31.50 |7.32 | |7.33.50 | ----+-----------------+-----------+----------+--------+--------+---- 12 |6-3/4 |7.36.55 |7.37 | |7.38.55 | 13 |6-7/8 paul. plus.|7.38. 5 |7.38 | |7.40. 0 | 14 |7-1/8 |7.39.45 |7.39 | |7.41.45 | 15 |7-1/4 paul. plus.|7.42.30 |7.42 | |7.44.30 | ----+-----------------+-----------+----------+--------+--------+---- 16 |7-1/2 |7.44. 6 |7.44 | |7.46. 6 | 17 |7-2/3 |7.46. 0 |7.46 | |7.48. 0 | 18 |8 ferè |7.48.25 |7.48 ferè | |7.50.25 | 19 |8-1/5 |7.51.15 |7.51 | |7.53.15 | ----+-----------------+-----------+----------+--------+--------+---- 20 |8-1/4 paul. plus.|7.53.37 |7.52 | |7.55.37 | 21 |8-3/4 |7.55.45 |7.56 ferè | |7.57.45 | 22 |8-3/4 paul. min. |7.59. 5 |7.59 | |8. 1. 5 | 4. 23 |8-1/5 |8. 6.30 |8. 6 | |8. 8.30 | {371} ----+-----------------+-----------+----------+--------+--------+---- 24 |7-3/4 |8.11.25 |8.12 | |8.13.25 | 5. 25 |7-1/4 ferè. |8.17.30 |8.18 | |8.19.30 | 26 |7 ferè. |8.19.41 |8.19 | |8.21.41 | 27 |5-7/8 |8.28. 8 |8.28 | |8.30. 8 | ----+-----------------+-----------+----------+--------+--------+---- 28 |5-1/2 ferè. |8.30.14 |8.30 | |8.32.14 | 29 |4-3/4 |8.36.25 |8.36 | |8.38.25 | 30 |3-5/8 |8.43.19 |8.43 | |8.45.19 | 31 |3-1/4 |8.46.12 |8.46 ferè.| |8.48.12 | ----+-----------------+-----------+----------+--------+--------+---- 32 |3 |8.47.32 |8.47 | |8.29.32 | 33 |2-3/4 |8.50.57 |8.50 | |8.52.57 | 34 |2-1/2 ferè |8.54.15 |8.54 | |8.56.15 | 35 |1-3/4 |8.58.24 |8.58 | |9. 0.24 | ----+-----------------+-----------+----------+--------+--------+---- 36 |1-1/8 |8.59.35 |8.59 | |9. 1.35 | 37 |0-5/6 |9. 1.38 |9. 1 | |9. 3.38 | 38 |0-1/2 |9. 3.20 |9. 3 |Altit. |9. 5.20 | 39 |Finis. |9. 6.53 |9. 6 |[Sun] |9. 8.53 | 6. ----+-----------------+-----------+----------+--------+--------+---- | |9.23. 6 | |47.33 |9.25 28 | | |9.24.16 | |47.42 |9.26.45 | | |9.28.29 | |48.10 |9.30.42 | | |9.30.36 | |48.28 |9.33.12 |

_Animadvertenda._

1. Quòd Sciatericum cum correcto tempore non omnino convenit, non-nisi Lineæ Meridianæ imputandum.

2. Initium circa 79 gr. à puncto _Zenith_ occasum versùs contigit.

3. Hujusque Semidiameter Lunæ æqualis extitit Solari.

4. Maxima obscuratio extitit digit. 8.25' hora 8.2'.

5. Hic Semidiameter _Lunæ/_ ad 8" vel 9" major apparuit.*

* _See Numb. 19 of the Philosophical Transactions, p. 347._

6. Punctum finis distitit à verticali ad Ortum 143 gr.

This Observation is by the same _Astronomer_, represented also by the _Figures AAAAAA_; as that of the _Horizontal Eclipse_ of the _Moon_, is, by the _Figures BB_.

{372}

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_The Figure of the Stars in the Constellation of _Cygnus_; together with the _New Star_ in it, discover'd some years since, and very lately seen by M. _Hevelius_ again._

The Relation concerning this _New Star_ in the _Brest of Cygnus_, very lately discover'd again at _Dantzick_, by M. _Hevelius_, was publish't _Numb_. 19. _p_. 349. The _Figure_ of that _Constellation_, with the _New Star_ in it, was thus, hastily drawn, sent over by that Observer.

{373}

* * * * *

_An Extract of a Letter written _Decemb. 28. 1666_. by M. _Auzout_ to the Publisher, concerning a way of his, for taking the _Diameters_ of the _Planets_, and for knowing the _Parallax_ of the _Moon_; as also the Reason, why in the _Solar Eclipse_ above calculated, the _Diameter_ of the _Moon_ did increase about the end._

I did apply my self the last Summer to the taking of the _Diameters_ of the Sun, Moon, and the other Planets, by a Method, which one M. _Picard_ and my self have, esteem'd by Us the best of all those, that have been practis'd hitherto; since we can take the _Diameters_ to _Second Minutes_, being able to divide one foot into 24000. or 30000. parts, scarce failing as much as in one only part, so as we can in a manner be _assur'd_, not to deceive our selves in 3. or 4. _seconds_. I shall not now tell you my Observations, but I may very well assure you, that the _Diameter_ of the _Sun_ has not been much less in his _Apogee_, than 31. m. 37. or 40. sec. and certainly not lesse than 31. m. 35. sec. and that at present in his _Perigee_ it passes not 32. m. 45. sec. and may be lesse by a second or two. That, which is at the present troublesome, is, that the _Vertical_ Diameter, which is the most easie to take, is diminisht, even at _Noon_, by 8. or 9. sec., because of the _Refractions_, which are much greater in Winter than Summer at the same height; and that the _Horizontal_ Diameter is difficult, because of the swift motion of the Heavens.

As for the _Moon_, I never yet found her Diameter less than 29. m. 44. or 45. sec. and I have not seen it pass 33. m. or if it hath, it was only by a few _seconds_. But I have not yet taken her in all the kinds of situations of the _Apogees_ and _Perigees_ which happen, with the _Conjunctions_ and _Quadratures_. I do not mention all, what can be deduced from thence, but if you have Persons at _London_, that observe these _Diameters_, we may entertain our selves more about this Subject, another time. I shall only tell you, that I have found a Way to know the _Parallax_ of the _Moon_, by the means of her _Diameter_: _Vid_. If on a day, when she is to be in her _Apogee_ or _Perigee_, and in the most _Boreal_ Signes, you take her Diameter towards the _Horizon_, and then towards the _South_, with her _Altitudes_ {374} above the Horizon. For, if the Observation of the Diameters be exact; as in these Situations the Moon changes not considerably her Distance from the Earth in 6. or 7. hours, the _Difference_ of the Diameters will shew the Proportion there is of her Distance, with the Semi-diameter of the Earth. I do not enlarge, because that as soon as one hath this _Idea_, the rest is easie. The same would yet be practis'd better in the places, where the Moon passes through the _Zenith_, than here, for the greater the difference is of the Heights, the greater is that of the Diameters. I do not note (for it easily appears) that, if one were under the same _Meridian_, or the same _Azimuth_ in two very different places, and took at the same time the Diameter of the Moon, one would do the same thing, though this Method goes not to preciseness.

From what has been said, may be collected the reason of the Observation, which M. _Hevelius_ made in the last _Eclipse of the Sun_, touching the increase of the Moon's Diameter about the end. I am exceeding glad, that a person, who probably knew not the cause of it, has made the Experiment: but it is strange, that until now no Astronomer has foreseen, that that should happen, nor given any precepts for the Change of the _Moons Diameter_ in the _Eclipses of the Sun_, according to the places, where they should happen, and according to the Hour and Height, the Moon should have. For, what hapned in that _Eclipse_ of Augmentation, would have faln out contrarily, if it had been in the Evening; for, the Moon, which in that _Eclipse_, that began in the Morning, was higher about the end than at the beginning, was nearer us, and consequently was to appear bigger: But if the _Eclipse_ should happen in the Evening, she would be lower at the end, and therefore more distant from us, and consequently appear lesser. So also in two different places, whereof one should have the Eclipse in the Morning, and the other at Noon, the Moon should appear bigger to him that hath it at Noon: And she must likewise appear bigger to those, who shall have a leser _Elevation_ of the _Pole_ under the same _Meridian_, because the Moon will be nearer them.

I wish, I could satisfie you about the _Optick Glasses_ of Signior _Burattini_ in _Poland_, which he hath sent hither; but I have not yet seen their performances my self. I only saw once the Glasses, {375} which are perfectly well wrought and well polisht. Those, that have tried them, find them very good; but they are only, the one of 10, the other of 8. foot. A good Astronomer told me, that they would bear a great _Aperture_ in respect of their length.

I do not well know, what to say to yours concerning M. _Hevelius_. Mean while, the interest of truth, and the obliging manner, he has treated me with, engage me to answer him, in the matter of the _Comets_: I am perswaded, I shall convince him; but since he hath taken the _Illustrious Royal Society_ for Judge, I accept that with all my heart.

* * * * *

_A Relation of the loss of the Way to prepare the _Bononian Stone_ for shining._

[Sidenote: * It is hoped notwithstanding (which also a late Letter from abroad does hint) that some or other of the _Italian_ Vertuosi at _Florence_ have secured this Secret.]

Though several Persons have pretended to know the Art of preparing and calcining the _Bononian_ Stone, for keeping a while the Light once imbibed; yet there hath been indeed but one, who had the true secret of performing it. This was an _Ecclesiastick_, who is now dead, without having left that skill of his to any one, as Letters from _Italy_ and _France_, some while since, did inform. There is no substance, in Nature, known to us, that hath the effect of this Stone; so that (to the shame of the present Age) this _Phænomenon_ is not like to be found any where, but in Books, except some happy _Genius_ light upon same or the like skill. *

* * * * *

_A Description of a _Swedish_ Stone, which affords _Sulphur_, _Vitriol_, _Allum_ and _Minium_._

This was communicated to the _R. Society_ by Sir _Gilbert Talbot_ Knight, a Worthy Member of that Body, as he had received it in _Denmark_, being his Majesties Extraordinary Envoy there; as follows,

There is a Stone in _Sweden_ of a Yellow Colour, intermixed with streaks of white (as if composed of Gold and Silver) and heavy withal. It is found in firm Rocks, and runs in Veins, {376} upon which they lay Wood, and set it on fire. When the Stone is thus heated, they cast Water upon it, to make it rend, and then dig it up with Mattocks. This done, they break it into smaller pieces; and put it into Iron-pots, of the shape represented by _Figure_ C; the mouth of the one going into the other. These they place, the _one_ in the Oven upon an Iron fork sloping, so that, the Stone being melted, it may run into the _other_, which stands at the mouth of the Oven, supported upon an Iron. The first running of the Stone is _Sulphur_.

The remainder of the burned Stone is carry'd out, and laid upon a high Hill, where it lies exposed to the Sun and Air for the space of two years, and then taketh fire of it self, casting forth a thin blew flame, scarce discernable in the day time. This being consumed, leaveth a blew dust behind it; which the Workmen observe, and mark with woodden pins. This they dig up, and carry into the Work-house, and put it into great Tubs of Water, where it infuseth 24. hours or more. The Water they afterward boyl in Kettles, as we do Saltpeter, and put it into cooling Tubs, wherein they place crosse Sticks, and on them the _Vitriol_ fastens, as Sugar-candy doth.

The Water, that remains after the extraction of the _Vitriol_, they mix with an eight part of Urin and the Lees of Wood-ashes, which is again boyled very strong, and being set to cool in Tubbs, crosse Sticks are likewise placed, and thereon the _Allum_ fastens.

In the Water, which remains after the _Allum_, is found a Sediment, which being separated from the Water, is put into an Oven, and Wood laid upon it and fired, till it become red, which makes the _Minium_, wherewith they paint their Houses, and make plaister.

_So far this Description_; Which gave occasion to a curious person to call to mind, That there was a kind of Stone in the _North_ of _England_, yielding the same substances, except _Minium_. {377}

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_A Relation of the Raining of _Ashes_, in the _Archipelago_, upon the Eruption of Mount _Vesuvius_, some years ago._

This came but lately to hand from that knowing person, Mr. _Henry Robinson_, and was thought fit to be now inserted here, that it might not be lost, though it hath hapned above 30 years ago. It was contained in a Letter, (subscribed by Capt. _Will. Badily_) in these words:

[Sidenote: * Some of these Ashes were produced by Mr. _John Evelyn_, before the _Royal Society_.]

The 6^{th.} of _December_ 1631, being in the Gulf of _Volo_, riding at Anchor, about ten of the Clock that Night, it began to rain Sand or Ashes, and continued till two of the Clock the next Morning. It was about two inches thick on the Deck, so that we cast it over board with Shovels, as we did Snow the day before: The quantity of a Bushel we brought home, and presented to several Friends *, especially to the Masters of _Trinity House_. There was in our Company, Capt. _John Wilds_ Commander of the _Dragon_, and Capt. _Anthony Watts_, Commander of the _Elisabeth_ and _Dorcas_. There was no Wind stirring, when these Ashes fell, it did not fall onely in the places, where we were, but likewise in other parts, as Ships were coming from St. _John D'Acre_ to our Port; they being at that time a hundred Leagues from us. We compared the Ashes together, and found them both one. If you desire to see the Ashes, let me know.

* * * * *

_An Extract Of A Letter not long since written from _Rome_, rectifying the Relation of _Salamanders_ living in Fire._

This came from that Expert Anatomist M. _Steno_, to Dr. _Croone Videl_. That a Knight called _Corvini_, had assured him, that, having cast a _Salamander_, brought him out of the _Indies_, into the Fire, the Animal thereupon swell'd presently, and then vomited store of thick slimy matter, which did put out the neighbouring Coals, to which the _Salamander_ retired immediately, putting them out again in the same manner, as soon as they {378} rekindled, and by this means saving himself from the force of the Fire, for the space of two hours, the Gentleman above-mentioned being then unwilling to hazard the Creature any further: That afterwards it lived nine Months: That he had kept it eleven Months without any other food, but what it took by licking the Earth, on which it moved, and on which it had been brought out of the _Indies_; which at first was covered with a thick moisture, but being dried afterwards, the Urin of the Animal served to moisten the same. After the eleven Months, the Owner having a mind to try, how the Animal would do upon _Italian_ Earth, it died three dayes after it had changed the Earth.

* * * * *

_An Account of several Engagements for Observing of Tydes._

Since nothing is more important for discovering the Cause of that Grand _Phænomenon_ of Nature, the _Flux_ and _Reflux of the Sea_, than a true and full _History of the Tydes_; the _Virtuosi_ of _England_ have of late (especially since the Publication of Dr. _Wallis_ his _Theory_ touching that _Apparence_) taken care, to direct and recommend in several parts of the World, and particularly in the most proper places of these _Ilands_, such Observations, as may contribute to the elucidating of that Subject.

And as formerly they have sent their _Inquiries_ of this Nature to the Isle of St. _Helena_, situated in the open Ocean beyond the _Æquinoctial_, and already received some account thereupon; so they have since dispatcht the like for the _Bermudas_, an _Isle_ that hath no less conveniency of situation for that purpose. And they intend (as will more amply appear, God permitting, in a short time) to lodge with such Masters of Ships and Pilots, as shall sayl into remote parts, very particular directions of that kind, to be printed at the _Royal Societies_ charges, and to be committed to the care of the Masters of _Trinity House_ for disposing of them to that end.

And, as for the Observations, to be made in these Kingdoms; 'tis hoped, that the Masters in the Art of Navigation at _Bristol_ (Mr. _Standridge_ and Mr. _Iff_) will undertake that business with affection and care: the former of these two having already (as we are informed from a good hand) made a Collection of the Tydes; {379} for some years past, and found them differing from former Observations and Tables; the other promising future diligence in this matter; noting in the mean time, that some Tydes of last Autumn were so far differing from former Observations, that neither he, nor any others there, could make any thing of it.

We must not omit here to mention the readiness, expressed by these worthy Gentlemen, Mr. _Rob. Boyle_, Sir _Rob. Moray_, and Mr. _Henry Powle_, for concurring in this Work; the first, having undertaken to recommend Observations of this nature, to be made, upon the _Western_ Coast of _Ireland_ *; the second, upon the West of _Scotland_; and the third, in the Isle of _Lundy_; to whom we must adde the inquisitive Mr. _Sam. Colepresse_, for _Plymouth_, and the _Lands-end_. Besides, we hope to engage the curious of _France_ in the same undertaking, especially for procuring, besides what is known already concerning that place, a very particular and exact account of the Tydes upon the Coast of _Britany_, where (especially about St. _Malo_) they are found to rise to admiration, even to 60, 70, and sometime 80, feet, at the New and Full Moon.

* The Observations particularly recommended for that Coast, are these;

1. At what hour it is High-water on the day of the New and Full Moon, upon every Cape and Bay of the Western Coast of _Ireland_.

2. How long after the New and Full Moon the highest Spring-tides fall out.

3. What are the perpendicular heights of the Flood, both at the ordinary, and the Spring-tydes.

* * * * *

_Some Suggestions for Remedies against _Cold_._

As there have been Remedies found out against excessive _Heat_, and Means of cooling Meat and Drink; so it was lately, on the occasion of the sharp Season, suggested, That Remedies might be thought on against _Cold_; and that particularly it might be inquired into,

1. What things in Nature, or by Art, or Mechanical contrivance will retain a warming Heat longest, or a melting or scorching Heat?

2. What will continue or maintain Fire longest?

Some that observe common practises and vulgar Trades, take notice, That _Joyners_ use _Leaden-Pots_ for their Glue, alledging for a Reason, That Lead, being a close Mettal, retains the heat {380} longer than other Mettals. _Cary_'s Warming-stone promised a warmth for six or eight hours; if it performed but for two or three hours, it would be of great use. 'Tis found by sad experience, how hurtful Bright Fires, and especially of Stone-coal are to the Eyes.

To retain Fire long, certain _Black_ Earths are useful, as we were newly informed by the Inquisitive Dr. _B._ That a Gentleman in _Sommertsetshire_, called Mr. _Speke_, had bountifully obliged _Ilminster_, and his Neighborhood, by a Black Fat-Earth lately found in his Park. But the same Correspondent adds, That he never saw any parallel to a _Sea-weed_, which he and some of his Fellow-Students had in _Cambridge_ in the mouth of a Barrel of good Oysters. It was smaller than Pease-halm, yet cut, it lasted two very great Fires of Sea-coal, burning bright in the midst of the Fire; and by a stroak of the Tongues, it fell into the Hearth, jingling like Mettal.

* * * * *

_A Relation of an uncommon Accident in two Aged Persons._

This was imparted by the above-mentioned Mr. _Colepresse_, who assures in his Letter, containing this Account, That the matter of fact was thorowly examined by himself, and that he was fully, and in all respects, satisfied of the truth thereof.