Philosophical Transactions/Volume 1/Number 21

From Wikisource
Jump to navigation Jump to search

Numb. 21.



Munday, January 21. 1666.

The Contents.

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,

Eclipsis Solaris
Observata An. 1666. D. 2. Julii, St. N. Mane, à Johanne Hevelio.

Ordo Phasium Quantitas Phasium. Temp. æstim. sec. horol ambulat Temp ex Sciother. Altitude
Tempus correct. Animadvertanda
H.   ′   ″ H.   ′   ″ O.   ′ H.   ′   ″ Quod Sciatericum cum correcto tempore non omnino convenit, non-nisi Lineæ Meridianæ imputandum.
5.51.11 5.51.  0 17.45 5.53.12
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 Initium circa 79 gr: à puncto Zenith occasum versus contigit.
1 0 dig. 6.57.30 5.59.30
2 0 dig. 7.  0.23 7.  0.  0 7.  2.23
3 1 7.  2.30 7.  2.  0 7.  4.30
4 1 dig. 7.  4.50 7.  5 ferè. 7.  6.50
5 1 ferè. 7.10.57 7.10 7.12.57
6 3 7.14.59 7.15 7.16.59
7 3 7.17.50 7.18 ferè. 7.19.50
8 4 dig. 7.21.35 7.21 7.23.35
9 4 7.23.43 7.23 ferè. 7.23.43
10 5 7.27.53 7.28 7.29.53 Hujusque Semidiameter Lunæ æqualis extitit Solari.
11 6 7.31.50 7.32 7.33.50
12 6 7.36.55 7.37 7.38.55
13 6 paul. plus. 7.38.  5 7.38 7.40.  0
14 7 7.39.45 7.39 7.41.45
15 7 paul. plus. 7.42.30 7.42 7.44.30
16 7 7.44.  6 7.44 7.46.  6
17 7 7.46.  0 7.46 7.48.  0
18 8 ferè. 7.48.25 7.48 ferè. 7.50.25
19 8 7.51.15 7.51 7.53.15
20 8 paul. plus. 7.53.37 7.52 7.55.37
21 8 7.55.45 7.56 ferè. 7.57.45
22 8 paul. min 7.59.  5 7.59 8.  1.  5 Maxima obscuratio extitit digit. 8.25′, hora 8.2′.
23 8 8.  6.30 8.  6 8.  8.30
24 7 8.11.25 8.12 8.13.25 Hic Semidiameter Lunæ ad 8th vel 9th major apparuit.*
*See Numb. 19. of the Philosophical Transactions, p. 347.
25 7 ferè. 8.17.30 8.18 8.19.30
26 7 fere. 8.19.41 8.19 8.21.41
27 5 8 30 14 8.30 8.32.14
28 5 fere. 8 36 14 8.30 8.32.14
29 4  8 36 25 8.36 8.38.25
30 4 8 43 19 8.43 8.45.19
31 3 8 46 12 8.46 ferè. 8.48.12
32 3 8.47.32 8.47 8.29.32
33 2 8.50.57 8.50 8  .2.57
34 2 fere. 8.54.15 8.54 8.56.15
35 1 8.58.24 8.58 9.  0.24
36 1 8.59.35 8.59 9.  1.35
37 0 9.  1.38 9.  1 9.  3.38
38 0 9.  3.20 9.  3 9.  5.20
39 Finis. 9.  6.53 9.  6. Altit. ☉ 9.  8.53 Punctum finis distitit à verticali ad Ortum 143 gr.
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

This Observation is by the same Astronomer, represented also by the Figures AAAAAAA; as that of the Horizontal Eclipse of the Moon, is, by the Figures BB.

Philosophical Transactions - Volume 1 - Number 21 - Figure A.png
Philosophical Transactions - Volume 1 - Number 21 - Figure AAAA.png
Philosophical Transactions - Volume 1 - Number 21 - Figure B.png
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 discoverd again at Dantzick, by M. Hevelius, was publish't Numb. 19. p. 349. The Figure of that Constellation with New Star in it, was thus, hastily draw, sent over by the Observer.

Philosophical Transactions - Volume 1 - Number 21 - figure.jpg

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 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 distant 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, not 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 the must likewise appear bigger to those, who shall have a lesser 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, 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 or 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.

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 [* 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.]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 the 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, 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.

Philosophical Transactions - Volume 1 - Number 21 - Figure C.png

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 like wise 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.

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:

THe 6th 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, * Some of these Ashes were produced by Mr. John Evelyn, before the Royal Society.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. Croon; 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 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 Society 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, 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 * 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.
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.

Some Suggestions
for Remedies against

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 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.

The Relation of the one, is in these words.

Joseph Shute Clerk, Parson of Mary (nigh Plymouth) in the County of Devon, aged 81 years, being a temperate man, and of an healthy constitution, having the in-most Grinder loose, and so remaining, perceived, that his mouth, about three Moneths since, was somewhat streightned; and upon inquiry, into the cause of it, found, That he had a new Tooth (the third Grinder) being the innermost of the upper Jaw in the Right Cheek, which still remains firm.

The Account of the other follows thus.

Maria Stert of Benecliffe, in Plympton St. Mary (near Plymouth) in Devon, aged about 75 years, an healthy person, having had nine children, about the fortieth year of her age lost three of her upper Incisores or Cutters, the other drawn out, and so remained Toothless, as to them, for about 25 years, when she perceived, that a new Tooth came forth (without any pain) next the Canini of the left Check: And about two years after, another Tooth grew out likewise without pain, close by the former. The first whereof, never came to above half the length of her former Cutters, the latter scarce breaking the skin: Both which yet proved serviceable, till about six weeks since, when she eating (no hard, crusty, or solid) Meat, that Tooth which came out first, fell down into her Mouth, without any loosness before hand perceived, or any pain; which had not a phang like other Cutters, but much less, and shorter. The other abides firm, and serviceable.

To the truth of these Relations, not onely the said Joseph Shute and Maria Stert, have put the one his name, the other her Mark, the third and seventh of January, 1666. but also Sir William Strode, and Mr. Colepresse have subscribed the same, as believing the Relation to be true.

An Account of two Books.

1. ISMAELIS BULLIALDI ad Astronomos Monita duo: Primum, De Stella Nova, quæ in Collo Ceti ante annos aliquot visa est. Alterum, De Nebuslosa in Andromedæ Cinguli parte Borca, ante biennium iterum orta.

The chief end of the Author in publishing this Tract, seems to be, To excite Astronomers to a diligent observation, both of that New Star in the Neck of the Whale, to be seen in February and March next; and of that other, in the Northern part of Andromeda's Girdle, to be seen at this very present.

As to the former of these Stars, he affirms, that, as it hath appeared for many years in the said place, so it will in the beginning of March next appear equal to the Stars of the third Magnitude, or perhaps bigger; and that about the end of the same Month, if the Crepuscle do not hinder, the greatest Phasis of it will appear, if so be, that it keep the same Analogy of Motions and Periods, which it observed from An. 1638, to An. 1664. Where he takes notice of the Causes, why its two greatest Appearances could not be seen, An. 1664, 1665, 1666; and how he comes to know, that in the beginning of March next, it will equal, or even exceed the Stars of the Third Magnitude, noting, that from the Observations hitherto made of this Star, it is manifest, that the greatest Phases thereof do every year anticipate by 32. or 33. dayes; forasmuch as An. 1660. its greatest Appearance was about the end of October and the beginning of November; An. 1661. about the end of September, or the beginning of October; An. 1662, about the end of August, &c. so that this year it must be in March, if the former Analogy do hold.

He collects also from the Observations, That one Period from the greatest Phasis to the next, consists of about 333. dayes: but that the interval of the time betwixt the times of its beginning to appear equal to the Stars of the Sixt Magnitude, and of its ending to do so, consists of about 120. dayes: And that its greatest Appearance lasts about 15. dayes: All which yet he would have understood with some latitude.

This done, he proceeds to the investigation of the Causes of the Vicissitudes in the Emersion and Dis-appearance of this Star, and having discoursed, That the apparent Increase and Decrement of every Lucid Body proceeds either from its changed distance from the Eye of the Observer; or from its various site and position in respect of him, whereby the angle of Vision is changed; or from the increase or diminution of the bulk of the lucid body it self: and having also demonstrated it impossible, that this Star should move in a Circle, or in an Ellipsis; and proved it improbable that it should move in a Strait Line; he concludes, that there can be no other genuin, or at least, no other more probable cause of its Emersion and Occultation, than this, That the bigger part of that round Body is obscure and inconspicuous to us, and its lesser part lucid, the whole Body turning about its own Center, and one Axe; whereby for one determinate space of time it exhibits its lucid part to the Earth, for another, subducts it: it not being likely, that fires should be kindled in the Body of that Star, and that the matter thereof should at certain times take fire and shine, at other times be extinguisht upon the consumption of that matter.

So far of that Star. As to the other in the Girdle of Andromeda, seen about the beginning of An. 1665; he relates, that, when in the end of 1664. the World beheld the then appearing Comet, Astronomers observed also this new Phænomenon, which was called by them Nebulosa in Cingulo Andromedæ. Concerning which, he notes, that the same had been already seen many years before by Simon Marius, vid. An. 1612. when with a Telescope he search'd for the Satellits of Jupiter, and observed their motions; alledging for proof hereof, the said Authors own words, out of his own Book, De Mundo Joviali, publisht An. 1614. And farther shews, that it hath formerly appear'd (about 150. years ago) and been taken notice off by an expert, though Anonymous, Astronomer; whose words he cites out of a Manuscript, brought out of Holland by the Excellent Jacobus Augustus Thuanus, returning from his Embassy to Paris; wherein also was marked the Figure of that Phænomenon, represented in print by our Author: who from all this collects, that, whereas this Star hath been seen formerly, and that 150. years since, but yet neither observed by Hipparchus, nor any other of the Antients, that we can find, nor also in the former Age by Tycho Brahe, nor in our Age, by Bayerus, and appear'd also in the Month of November last (wherein he wrote this Tract) much lessened and obscure, after it had, two years ago, shone very bright; that therefore it must needs appear and dis-appear by turns, like those in the Necks of the Whale and Swan.

II. ENTRIENS sur les Vies et sur les Ouvrages Des plus excellens Peintres, Anciens et Modernes, par Monsieur FELIBIEN.

This Author, having first discoursed of that Royal Pallace the Louvre, and the Designs of finishing it; passes on to the Art of Picturing, and treats of the three principal things, wherein a good Master of the Art must excel, vid. the Composition, Designing, and Laying on of Colours, which done, he ravels into the Origine, and deduces the Progress of Painting, and relates what is most remarkable in the Lives of the Antient Painters: And among many particulars, he observes in the Life of Andreas de Sarte, how difficult it is, to judge well of a Picture; relating, that a Duke of Mantua, having obtained of Clement VII. a Pourtrait of Leo X. which had been done by Raphael Urbin, and was at Florence, those of that Town being unwilling to lose so excellent a piece, caused a Copy thereof to be made by the said Andreas de Sarte, which they sent instead of the Original. This Copy was so perfect, that Julio Romano, who had been bred and taught by Raphael, and was one of the best Painters of Italy, took it for an Original; and would never have been undeceived, if one Vasari had not assured him, that it was but a Copy, which himself had seen made, and had not shew'd him certain marks, that were there put to discriminate it from the Original.

In the Second Part, the Author has set down all that is requisite to judge and discourse well of Painting. But, to add Examples to Precepts, he discourses of the Modern Painters, and making a Description of their best Works, he takes occasion to observe, what is there found most excellent, and to shew, how they have put in practice the Rules of Art. He treats also of the declining of Painting, and affirms, that nothing considerable hath been done in it from the time of Constantine, till An., 1240; when one, Cimabue, began to raise this Art again. After this, he gives a List of the Painters, that since have been famous for their Works, preferring before all others, Raphael Urbin. The last of all is the above-mention'd Andre de Sartes, who died, An. 1530. and whom the liberality of Francis I. had drawn into France.

The Printing of these Tracts is now return'd to the first Printer thereof, as being somewhat re-setled after the late sad Fire of London.


In the SAVOY
Printed by T. N. for John Martyn, Printer to the Royal Society, and are to be sold at his Shop a little without Temple-Bar, 1667.