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of the spherical form, that although the
moon, or the earth, were it absolutely Observations on the Moon-Nebule- smooth, would indeed be a more perfect Saturn—Venus-Mars.
sphere than in its present rough state, yet
touching the perfection of the earth, THERE were other discoveries an- considered as a natural body calculated nounced in Galileo's book of great and for a particular purpose, every one must unprecedented importance, and which see that absolute smoothness and sphescarcely excited less discussion than the ricity would make it not only less percontroverted Medicæan planets. His fect, but as far from being perfect as observations on the moon threw addı- possible. “ What else," he demanded, tional light on the constitution of the “would it be but a vast unblessed desert, solar system, and cleared up the difficul- void of animals, of plants, of cities and ties which encumbered the explanation of men ; the abode of silence and inacof the varied appearance of her surface. tion; senseless, lifeless, soulless, and The different theories current at that stript of all those ornaments which make day, to account for these phenomena, are it now so various and so beautiful ?" collected and described by Benedetti, He reasoned to no purpose with and also with some liveliness, in a my- the slaves of the ancient schools: nothological poem, by Marini.* We are thing could console them for the detold, that, in the opinion of some, the struction of their smooth unalterable dark shades on the moon's surface arise surface, and to such an absurd length from the interposition of opaque bodies was this hallucination carried, that one floating between her and the sun, which opponent of Galileo, Lodovico delle prevents his light from reaching those Colombe, constrained to allow the eviparts : others thought, that on account dence of the sensible inequalities of the of her vicinity to the earth, she was moon's surface, attempted to reconcile partly tainted with the imperfection of the old doctrine with the new observaour terrestrial and elementary nature, tions, by asserting, that every part of the and was not of that entirely pure and moon, which to the terrestrial observer refined substance of which the more appeared hollow and sunken, was in remote heavens consist: a third party fact entirely and exactly filled up with looked on her as a vast mirror, and a clear crystal substance, perfectly immaintained that the dark parts of her perceptible by the senses, but which surface were the reflected images of our restored to the moon her accurately earthly forests and mountains.
spherical and smooth surface. Galileo Galileo's glass taught him to believe met the argument in the manner most that the surface of this planet, far from fitting, according to one of Aristotle's being smooth and polished, as was gene- own maxims, that“ it is foolish to rerally taken for granted, really resembled fute absurd opinions with too much our earth in its structure; he was able dis- curiosity." Truly,” says he, “ the tinctly to trace on it the outlines of moun- idea is admirable, its only fault is that tains and other inequalities, the summits it is neither demonstrated nor demonstraof which reflected ihe rays of the sun ble; but I am perfectly ready to believe before these reached the lower parts, it, provided that, with equal courtesy, and the sides of which, turned from his I may be allowed to raise upon your beams, lay buried in deep shadow. He smooth surface, crystal mountains(which recognised a distribution into something nobody can perceive) ten times higher similar to continents of land, and than those which I have actually seen oceans of water, which reflect the sun's and measured.” By threatening to prolight to us with greater or less vivacity, ceed to such extremities, he seems to according to their constitution. These have scared the opposite party into moconclusions were utterly odious to the deration, for we do not find that the Aristotelians; they had formed a pre- crystalline theory was persevered in. conceived notion of what the moon In the same essay, Galileo also exought to be, and they loathed the doc- plained at some length the cause of that trines of Galileo, who took delight, as part of the moon being visible, which is they said, in distorting and ruining the unenlightened directly by the sun in her fairest works of nature. It was in vain first and last quarter. Maestlin, and behe argued, as to the imaginary perfection fore him Leonardo da Vinci, had already
declared this to arise from what may • Adone di Marini, Venetiis, 1623, Cant. x.
be called earthshine, or the reflec.
tion of the sun's light from the terres- sufficiently to detain his attention from trial globe, exactly similar to that which his telescope and astronomical observathe moon affords us when we are simi- tions; but he knew too well where his larly placed between her and the sun; but real strength lay, and they had scarcely the notion had not been favourably re- time to compound any thing like an arceived, because one of the arguments gument against him and his theories, against the earth being a planet, revolv- before they found him in possession of ing like the rest round the sun, was, that some new facts, which they were unit did not shine like them, and was prepared to meet, otherwise than by therefore of a different nature; and this the never-failing resource of abuse and argument, weak as it was in itself, the affected contempt. The year had not theory of terrestrial reflection completely expired before Galileo had new intellioverturned. The more popular opinions gence to communicate of the highest imascribed this feeble light, some to the portance. Perhaps he had been taught fixed stars, some to Venus, some to the caution from the numerous piracies which rays of the sun, penetrating and shining had been committed upon his discoveries, through the moon. Even the sagacious and he first announced his new discoBenedetti adopted the notion of this veries enigmatically, veiling their real light being caused by Venus, in the import by transpositions of the letters in same sentence in which he explains the the words which described them, (a practrue reason of the faint light observed tice then common, and not disused even during a total eclipse of the moon, points at a much later date,) and inviting all ing out that it is occasioned by those astronomers to declare, within a certain rays of the sun, which reach the moon, time, if they had noted any thing new after being bent round the sides of in the heavens worthy of observation, the earth by the action of our atmo- The transposed letters which he published sphere.* Galileo also announced the detection
"Smaismrmilne poeta leumi bune nugttaviras." of innumerable stars, invisible to the Kepler, in the true spirit of his riddling unassisted sight; and those remark- philosophy, endeavoured to decypher the able appearances in the heavens, ge- meaning, and fancied he had succeeded nerally called nebulæ, the most con
when he formed a barbarous Latin siderable of which is familiar to all
verse, under the name of the milky way, when
“Salve umbistineum geminatum Martia proles," examined by his instrument, were found conceiving that the discovery, whatever to resolve themselves into a vast collec- it might be, related to the planet Mars, tion of minute stars, too closely congre- to which Kepler's attention had before gated to produce a separate impression been particularly directed. The reader, upon the unassisted eye.t. Benedetti
, however, need 'not weary himself in who divined that the dark shades on the seeking 'a translation of this solution, moon's surface arose from the constitu- for at the request of the Emperor Rotion of those parts which suffered much dolph, Galileo speedily sent to him the of the light to pass into them, and con
real readingsequently reflected a less portion of it, had maintained that the milky way was
Altissimum planetam tergeminum observavi ; the result of the converse of the same
that is,“ I have observed that the most phenomenon, and declared, in the lan- distant planet is triple," or, as he further guage of his astronomy, that it was a explains the matter, “ I have with great part of the eighth orb, which did not, admiration observed that Saturn is not like the rest, allow the sun's light to
a single star, but three together, which traverse it freely, but reflected a small
as it were touch each other; they have no part feebly to our sight.
relative motion, and are constituted in The Anti-Copernicans would probably this form o0o the middle being some
If have been well pleased, if by these eter- what larger than the lateral ones. nally renewed discussions and disputes,
we examine them with an eye-glass which they could have occupied Galileo's time magnifies the surface less than 1000
times, the three stars do not appear Speculat. Lib Venetiis, 1585, Epistolæ. + This opinion, with respect to the milky way,
very distinctly, but Saturn has an obbeen held by some of the ancient astronomers. See long appearance, like the appearance of
an olive, thus O. Now I have dis“ Anne magis densú stellarum turba corona Conterit Hammas, et crisso lumine candet,
covered a court for Jupiter, and two Et fulgore nitet collato clarior vrbis."
servants for this old man, who aid his
Manilius. Lib. i. v. 753.
steps and never quit his side." Galileo seeing the enlightened portion in each was, however, no match in this style position assume the form appropriate to of writing for Kepler, who disapproved that hypothesis. It was with reason, his friend's metaphor, and, in his usual therefore, that he laid stress on the ima fanciful and amusing strain," I will portance of this observation, which also not," said he,“ make an old man of established another doctrine scarcely less Saturn, nor slaves of his attendant obnoxious to the Anti - Copernicans, globes, but rather let this tricorporate namely, that a new point of resemblance form be Geryon, so shall Galileo be was here found between the earth and Hercules, and the telescope his club; one of the principal planets; and as the armed with which, he has conquered reflection from the earth upon
the moon that distant planet, and dragged him had shewn it to be luminous like the from the remotest depths of nature, and planets when subjected to the rays of exposed him to the view of all." Gali- the sun, so this change of apparent leo's glass was not of sufficient power to figure demonstrated that one of the shew him the real constitution of this planets not near the earth, and thereextraordinary planet; it was reserved fore probably all, were in their own for Huyghens, about the year 1656, to nature not luminous, and only reflected declare to the world that these supposed the sun's light which fell upon them; attendant stars are in fact part of a an inference, of which the probability ring which surrounds, and yet is com- was still farther increased a few years pletely distinct from the body of Saturn;* later by the observation of the transit of and the still more accurate observations Mercury over the sun's disc. of Herschel have ascertained that it It is curious that only twenty-five consists of two concentric rings revolv- years before this discovery of the phases ing round the planet, and separated (or appearances) of Venus, a commenfrom each other by a space which our tator of Aristotle, under the name of most powerful telescopes scarcely enable Lucillus Philalthæus, had advanced the us to measure.
doctrine that all the planets except the Galileo's second statement concluded moon are luminous of themselves, and with the remark, that " in the other pla- in proof of his assertion had urged, nets nothing new was to be observed ;" “ that if the other planets and fixed but a month had scarcely elapsed, before stars received their light from the sun, he communicated to the world another they would, as they approached and reenigma,
ceded from him, or as he approached and
receded from them, assume the same Hæc immatura d me jam frustra leguntur oy,
phases as the moon, which, he adds, which, as he said, contained the an
we have never yet observed."—He furnouncement of a new phenomenon, in ther remarks, - that Mercury and Vethe highest degree important to the truth nus would, in the supposed case of their of the Copernican system. The inter- being nearer the earth than the sun, pretation of this is,
eclipse it occasionally, just as eclipses Cynthiæ figuras æmulatur mater amorum,
are occasioned by the moon.” Perhaps it is still more remarkable, that these
very that is to say,--Venus rivals the ap- passages, in which the reasoning is so pearances of the moon — for Venus correct
, though the facts are too hastily being now arrived at that part of her taken for granted, (the common error of orbit in which she is placed between the that school,) are quoted by Benedetti, exearth and the sun, and consequently, pressly to shew the ignorance and prewith only a part of her enlightened sur- sumption of the author. Copernicus, face turned towards the earth, the tele- whose want of instruments had prescope shewed her in a crescent form, like vented him from observing the horned the moon in a similar position, and tra- appearance of Venus when between cing her through the whole of her orbit the earth and sun, had perceived how round the sun, or at least so long as she formidable an obstacle the non-appearwas not invisible from his overpowering ance of this phenomenon presented to light, Galileo had the satisfaction of his system; he endeavoured, though
unsatisfactorily, to account for it by • Hayghens annonnced his discovery in this form : da a aa aacccccdeeee e ghiiiiiiilllimman supposing that the rays of the sun * ann n n N O OU OP P Irrsitettu uu u u, which he passed freely through the body of the cingitur, tenui, planu, nusquam cohærente, ad eclipti planet, and Galileo takes occasion to cam inclinato. De Saturni Lunâ, Hage, 1656. praise him for not being deterred from adopting the system, which, on the whole, much dissatisfaction to all those who appeared to agree best with the phe- were connected with that university. nomena, by meeting with some which it Perhaps not fully appreciating his dedid not enable him to explain. Milton, sire of returning to his native country, whose poem is filled with allusions to and the importance to him and to the Galileo and his astronomy, has not suf- scientific world in general, of the comfered this beautiful phenomenon to pass plete leisure which Cosmo secured to unnoticed. After describing the creation him at Florence, (for by the terms of his of the Sun, he adds :
diploma he was not even required to reHither, as to their fountain, other stars
side at Pisa, nor to give any lectures, Repairing, in their golden urus draw light, And hence the morning planet gilds her horns.* : except on extraordinary occasions, to
Galileo also assured himself, at the sovereign princes and other strangers of same time, that the fixed stars did not distinction.) the Venetians remembered receive their light from the sun. This he only that they had offered him an hoascertained by comparing the vividness nourable asylum when almost driven of their light, in all positions, with the from Pisa; that they had increased his feebleness
of that of the distant planets, salary to four times the sum which any and by observing the different degrees previous professor had enjoyed; and, of brightness with which all the planets finally, by an almost unprecedented deshone at different distances from the cree, that they had but just secured him sun. The more remote planets did not, in his post during the remainder of his of course, afford equal facilities with life. Many took such offence as to Venus for so decisive an observation;
refuse to have any further communicabut Galileo thought he observed, that tion with him; and Sagredo, a constant when Mars was in quadratures, (or in friend of Galileo, wrote him word that the quarters, the middle points of his he had been threatened with a similar path on either side,) his figure varied desertion unless he should concur in slightly from a perfect circle. Galileo the same peremptory resolution, which concludes the letter, in which he an
threats, however, Sagredo, at the same nounces these last observations to his time, intimates his intention of braving. pupil Castelli, with the following ex- Early in the year 1611, Galileo made pressions, shewing how justly he esti. his first appearance in Rome, where he mated the opposition they encounter
was received with marks of distinguished ed :-“ You almost make me laugh by consideration, and where all ranks were saying that these clear observations are
eager to share the pleasure of contemsufficient to convince the most obstinate: plating the new discoveries. “Whether it seems you have yet to learn that long we consider cardinal, prince, or prelate, ago the observations were enough to he found an honourable reception from convince those who are capable of rea- them all, and had their palaces as open soning, and those who wish to learn and free to him as the houses of his prithe truth ; but that to convince the ob- vate friends."* Among other distincstinate, and those who care for nothing tions he was solicited to become a membeyond the vain applause of the stupid ber of the newly-formed philosophical and senseless vulgar, not even the testi- society, the once celebrated Academia mony of the stars would suffice, were Lincea, to which he readily assented. they to descend on earth to speak for the founder of this society was Federigo themselves. Let us then endeavour to Cesi, the Marchese di Monticelli, a young procure some knowledge for ourselves, Roman nobleman, the devotion of whose and rest contented with this sole satis time and fortune to the interests of scifaction ; but of advancing in popularence has not been by any means reopinion, or gaining the assent of the warded with a reputation commensurate book-philosophers, let us abandon both with his deserts. If the energy of his the hope and the desire."
mind had been less worthily employed
than in fostering the cause of science and CHAPTER IX.
truth, and in extending the advantages Account of the Academia Lincea-Del of his birth and fortune to as many as
Cimento- Royal Society. were willing to co-operate with him, the Galileo's resignation of the mathema- name of Federigo Cesi might have aptical professorship at Padua occasioned peared more prominently on the page of * B. vii. v. 364. Other passages may be examined
history. Cesi had scarcely completed in B. i. 286 ; iii. 565-590, 722—733 ; iv, 589; v, 261, 414; vii. 577; viii. 1-178. :
Salusbury, Math, Coll.
his 18th year, when, in 1603, he formed be learned from the habits of constant the plan of a philosophical society, correspondence with each other, and which in the first instance consisted alternate offices of counsel and assistonly of himself and three of his most ance.—Let the first fruits of wisdom be intimate friends, Hecke, a Flemish phy- love; and so let the Lynceans love each sician, Stelluti, and Anastasio de Filiis, other as if united by the strictest ties, Cesi's father, the Duca d'Acquasparta, nor suffer any interruption of this sinwho was of an arbitrary and extravagant cere bond of love and faith, emanating temper, considered such pursuits and from the source of virtue and philosophy. associates as derogatory to his son's -Let them add to their names the title rank; he endeavoured to thwart the de- of Lyncean, which has been advisedly sign by the most violent and unjusti- chosen as a warning and constant stifiable proceedings, in consequence of mulus, especially when they write on which, Cesi in the beginning of 1605 any literary subject, also in their private
in obliged to leave Italy altogether from ral when any work comes from them fear of the Inquisition, which was excited wisely and well performed.—The Lynagainst him, and the academy was for ceans will pass over in silence all poli a time virtually dissolved. The details tical controversies and quarrels of every of these transactions are foreign to the kind, and wordy disputes, especially present narrative: it will be enough to gratuitous ones, which give occasion mention that, in 1609, Cesi, who had to deceit, unfriendliness, and hatred; never altogether abandoned his scheme, like men who desire peace, and seek to found the opposition decaying which he preserve their studies free from molestaat first experienced, and with better suc- tion, and to avoid every sort of disturbcess he renewed the plan which he had ance. And if any one by command of sketched six years before. A few extracts his superiors, or from some other nefrom the Regulations will serve to shew cessity, is reduced to handle such matthe spirit in which this distinguished ters, since they are foreign to physical society was conceived:
and mathematical science, and conse“The Lyncean Society desires for its quently alien to the object of the Acaacademicians, philosophers eager for demy, let them be printed without the real knowledge, who will give them- Lyncean name." selves to the study of nature, and espe- The society which was eventually orcially to mathematics; at the same time ganized formed but a very trifling part it will not neglect the ornaments of ele- of the comprehensive scheme which gant literature and philology, which Cesi originally proposed to himself; it like a graceful garment adorn the whole had been his wish to establish a scienbody of science.--In the pious love of tific Order which should have correwisdom, and to the praise of the most sponding lodges in the principal towns of good and most high God, let the Lyn- Europe, and in other parts of the globe, ceans give their minds, first to obser- each consisting of not more than five nor vation and reflection, and afterwards less than three members, besides an unto writing and publishing.--It is not limited number of Academicians not within the Lyncean plan to find leisure restricted to any particular residence or for recitations and declamatory assem- regulations. The mortifications and blies; the meetings will neither be fre- difficulties to which he was subjected quent nor full, and chiefly for transact- from his father's unprincipled behaviour, ing the necessary business of the society: render it most extraordinary and admibut those who wish to enjoy such exercises rable that he should have ventured to will in no respect be hindered, provided undertake even so much as he actually they attend them as accessory studies, carried into execution. He promised to decently and quietly, and without furnish to the members of his society making promises and professions of such assistance as they might require in how much they are about to do. For the prosecution of their respective rethere is ample philosophical employment searches, and also to defray the charges for every one by himself
, particularly if pains are taken in travelling and in • Perhaps it was to deprecate the hostility of the the observation of natural phenomena, Lynceans are directed to address their prayers,
Jesuits that, at the close of these Regulations, the and in the book of nature which every among other Saints, especially to Ignatius Loyola, one has at home, that is to say, the
as to one who greatly favoured the interests of learn
ing. Odescalchi. Memorie dell' Acad. de' Lincei, heavens and the earth; and enough may Roma. 1806.