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of a soldier or statesman. The life of and ancient Florentine family, which, a man who is shut up during the greater in the middle of the fourteenth century, part of his time in his study or labora- adopted this surname instead of Bonatory supplies but scanty materials for juti, under which several of their anpersonal details; and the lapse of time cestors filled distinguished offices in the rapidly removes from us the opportuni. Florentine state. Some misapprehenties of preserving such peculiarities as sion has occasionally existed, in consemight have been worth recording. An quence of the identity of his proper account of it will therefore consist chiefly name with that of his family ; his most in a review of his works and opinions, correct appellation would perhaps be and of the influence which he and they Galileo de Galilei, but the surname have exercised over his own and suc- usually occurs as we have written it. ceeding ages. Viewed in this light, few He is most commonly spoken of by lives can be considered more interesting his Christian name, agreeably to the Itathan that of Galileo ; and if we compare lian custom ; just as Sanzio, Buonarotti, the state in which he found, with that in Sarpi, Reni, Vecelli, are universally which he left, the study of nature, we known by their Christian names of Rashall feel how justly an enthusiastic phael, Michel Angelo, Fra Paolo, Guipanegyric pronounced upon the age do, and Titian. immediately following him may be trans- Several authors have followed Rossi ferred to this earlier period. “This is the in styling Galileo illegitimate, but without age wherein all men's minds are in a having any probable grounds even when kind of fermentation, and the spirit of they wrote, and the assertion has since wisdom and learning begins to mount been completely disproved by an inspecand free itself from those drossie and tion of the registers at Pisa and Florence, terrene impediments wherewith it has in which are preserved the dates of his been so long clogged, and from the in- birth, and of his mother's marriage, sipid phlegm and caput mortuum of eighteen months previous to it.* useless notions in which it hath endured His father, Vincenzo Galilei, was a so violent and long a fixation. This is man of considerable talent and learning, the age wherein, methinks, philosophy with a competent knowledge of mathecomes in with a spring tide, and the pe- matics, and particularly devoted to the ripatetics may as well hope to stop the theory and practice of music, on which current of the tide, or, with Xerxes, to he published several esteemed treatises. fetter the ocean, as hinder the overflowing The only one which it is at present easy of free philosophy. Methinks I see how to procure—his Dialogue on ancient and all the old rubbish must be thrown away, modern music-exhibits proofs, not only and the rotten buildings be overthrown of a thorough acquaintance with his and carried away, with so powerful an subject, but of a sound and vigorous inundation. These are the days that must understanding applied to other topics lay a new foundation of a more magnifi- incidentally discussed. There is a pascent philosophy, never to be overthrown, sage in the introductory part, which that will empirically and sensibly can- becomes interesting when considered as vass the phenomena of nature, deducing affording some traces of the precepts the causes of things from such originals by which Galileo was in all probability in nature as we observe are producible trained to reach his preeminent station by art, and the infallible demonstration in the intellectual world.
“ It appears of mechanics: and certainly this is the to me," says one of the speakers in the way, and no other, to build a true and dialogue, “ that they who in proof of permanent philosophy."**
any assertion rely simply on the weight of authority, without adducing any ar
gument in support of it, act very CHAPTER II.
absurdly: I, on the contrary, wish to be
allowed freely to question and freely to Galileo's Birth--Family-Education
answer you without any sort of adulaObservation of the Pendulum—Pul- tion, as well becomes those who are silogies - Hydrostatical Balance— truly in search of truth." Sentiments Lecturer at Pisa.
like these were of rare occurrence at Galileo Galilei was born at Pisa, on
the close of the sixteenth century, and it is the 15th day of February, 1564, of a noble
Erythræus, Pinacotheca, vol. i. ; Salusbury's • Power's Experimental Philosophy, 1663, Life of Galileo. Nelli, Vita di Gal. Galilei,
to be regretted that Vincenzo hardly he was then living. These two were
the university of his native town, Pisa.• De his quæ diu vivunt, Patavii, 1612. his father at this time intending thai
.N. 2. 6
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he should adopt the profession of me- employed in ascertaining the rate of the dicine. In the matriculation lists at Pisa, pulse, and its variation from day to he is styled Galileo, the son of Vincenzo day. He immediately carried the idea Galilei, a Florentine, Scholar in Arts, into execution, and it was for this sole It is dated 5th November, 1581. Vi- and limited purpose that the first penviani, his pupil, friend, and panegy- dulum was constructed. Viviani tells rist, declares that, almost from the us, that the value of the invention was first day of his being enrolled on the rapidly appreciated by the physicians of lists of the academy, he was noticed the day, and was in common use in for the reluctance with which he lis- 1654, when he wrote. tened to the dogmas of the Aristote- Santorio, who was professor of medilian philosophy, then universally taught; cine at Padua, has given representaand he soon became obnoxious to tions of four different forms of these the professors from the boldness with which he promulgated what they styled his philosophical paradoxes. His early habits of free inquiry were irreconcileable with the mental quietude of
NO3 his instructors, whose philosophic doubts, when they ventured to entertain any, were speedily lulled by a quota
Non 30 tion from Aristotle. Galileo thought himself capable of giving the world an example of a sounder and more original mode of thinking; he felt himself destined to be the founder of a new school of rational and experimental philosophy. Of this we are now se
. curely enjoying the benefits; and it is difficult at this time fully to appreciate the obstacles which then presented themselves to free inquiry: but we shall see, in the course of this narrative, how arduous their struggle was who happily effected this important re
instruments, which he calls pulsilogies, volution. The vindictive rancour with (pulsilogias,) and strongly recommends which the partisans of the old phi- to medical practitioners. * These instrulosophy never ceased to assail Galileo ments seem to have been used in the is of itself a sufficient proof of the following manner: No. 1 consists merely prominent station which he occupied of a weight fastened to a string and a in the contest.
graduated scale. The string being gather Galileo's earliest mechanical disco- ed up into the hand till the vibrations of very, to the superficial observer appa
the weight coincided with the beatings of rently an unimportant one, occurred the patient's pulse, the length was ascerduring the period of his studies at Pisa. tained from the scale, which, of course, His attention was one day arrested by if great, indicated a languid, if shorter, the vibrations of a lamp swinging from
a more lively action. In No. 2 the imthe roof of the cathedral, which, whether provement is introduced of connecting great or small , seemed to recur at equal latter is regulated by the turns of a peg
the scale and string, the length of the intervals. The instruments then employed for measuring time were very showed the measure.
at a, and a bead upon the string at b imperfect: Galileo attempted to bring
No. 3 is still his observation to the test before quit
more compact, the string being shortting the church, by comparing the vi- ened by winding upon an axle at the brations with the beatings of his own
back the dial-plate. The construcpulse, and his mind being then princi- tion of No. 4, which Santorio claims as pally employed upon his intended pro
his own improvement, is not given, but fession, it occurred to him, when he had it is probable that the principal index, further satisfied himself of their regula- by its motion, shifted a weight to differ. rity by repeated and varied experiments, ent distances from the point of suspenthat the process he at first adopted sion, and that the period of vibration might be reversed, and that an instrument on this principle might be usefully • Comment, in Avicennam. Venetiis, 1625.
was still more accurately adjusted by a gress soon revealed the true nature of smaller weight connected with the se- his pursuits : Vincenzo yielded to the cond index. Venturi seems to have irresistible predilection of his son's mind, mistaken the third figure for that of a and no longer attempted to turn him pendulum clock, as he mentions this as from the speculations to which his whole one of the earliest adaptations of Gali- existence was thenceforward abandoned. leo's principle to that purpose* ; but it After mastering the elementary wriis obvious, from Santorio's description, ters, Galileo proceeded to the study of that it is nothing more than a circular Archimedes, and, whilst perusing the scale, the index showing, by the figure Hydrostatics of that author, composed to which it points, the length of string his earliest work,-an Essay on the Hyremaining unwound upon the axis. We drostatical Balance. In this he explains shall, for the present, postpone the con- the method probably adopted by Archisideration of the invention of pendulum medes for the solution of Hiero's celeclocks, and the examination of the dif- brated questions, and shows himself ferent claims to the honour of their first already well acquainted with the true construction.
principles of specific gravities. This At the time of which we are speaking, essay had an immediate and important Galileo was entirely ignorant of mathe- influence on young Galileo's fortunes, matics, the study of which was then at a for it introduced him to the approving low ebb, not only in Italy, but in every notice of Guido Ubaldi, then one of part of Europe. Commandine had re- the most distinguished mathematicians cently revived a taste for the writings of of Italy. At his suggestion Galileo apEuclid and Archimedes, and Vieta Tar- plied himself to consider the position of talea and others had made considerable the centre of gravity in solid bodies, a progress in algebra, Guido Ubaldi and choice of subject that sufficiently showed Benedetti had done something towards the estimate Ubaldi had formed of his establishing the principles of statics, talents; for it was a question on which which was the only part of mechanics Commandine had recently written, and as yet cultivated; but with these incon- which engaged at that time the attention siderable exceptions the application of of geometricians of the highest order. mathematics to the phenomena of na- Galileo tells us himself that he discontiture was scarcely thought of. Galileo's nued these researches on meeting with first inducement to acquire a knowledge Lucas Valerio's treatise on the same of geometry arose from his partiality for subject. Ubaldi was so much struck with drawing and music, and from the wish the genius displayed in the essay with to understand their principles and the which Galileo furnished him, that he inory. His father, fearful lest he should troduced him to his brother, the Cardi. relax his medical studies, refused nal Del Monte: by this latter he was openly to encourage him in this new mentioned to Ferdinand de Medici, the pursuit ; but he connived at the instruc- reigning Duke of Tuscany, as a young tion which his son now began to receive man of whom the highest expectations in the writings of Euclid, from the might be entertained. By the Duke's tuition of an intimate friend, named patronage he was nominated, in 1589, Ostilio Ricci, who was one of the pro- to the lectureship, of mathematics at fessors in the university. Galileo's Pisa, being then in his twenty-sixth year. whole attention was soon directed to the His public salary was fixed at the insignienjoyment of the new sensations thus ficant sum of sixty crowns annually, but communicated to him, insomuch that he had an opportunity of greatly adding Vincenzo, finding his prognostics veri- to his income by private tuition. fied, began to repent his indirect sanction, and privately requested Ricci to in
CHAPTER III. vent some excuse for discontinuing his Galileo at Pisu-Aristotle-Leonardo lessons. But it was fortunately too late ; da Vinci —Galileo becomes a Coperthe impression was made and could not nican —Urstisius—Bruno— Experibe effaced; from that time Hippocrates ments on falling bodies-Galileo at and Galen lay unheeded before the Padua-Thermometer. young physician, and served only to conceal from his father's sight the mathe. No sooner was Galileo settled in his matical volumes on which the whole of new office than he renewed his inquiries his time was really employed.
llis pro- creased diligence. He instituted a course
into the phenomena of nature with in* Essai sur les Ouvrages de Leonard da Vinci. Paris, 1797.
► See Treatise on HYDROSTATICS.
of experiments for the purpose of put- 'their discovery, a contemporary student ting to the test the mechanical doctrines, with Galileo at Pisa. Kopernik, or, as of Aristotle, most of which he found vin- he is usually called, Copernicus, a nasupported even by the pretence of ex- tive of Thorn in Prussia, had published perience. It is to be regretted that we his great work, De Revolutionibus, in do not more frequently find detailed his 1543, restoring the knowledge of the method of experimenting, than occasion- true theory of the solar system, and his ally in the course of his dialogues, and opinions were gradually and silently it is chiefly upon the references which gaining ground. he makes to the results with which the It is not satisfactorily ascertained at experiments furnished him, and upon what period Galileo embraced the new the avowed and notorious character of astronomical theory. Gerard Voss attrihis philosophy, that the truth of these butes his conversion to a public lecture accounts must be made to depend. Ven- of Mæstlin, the instructor of Kepler; and turi has found several unpublished pa- later writers (among whom is Laplace) pers by Galileo ori the subject of motion, repeat the same story, but without rein the Grand Duke's private library at ferring to any additional sources of inFlorence, bearing the date of 1590, in formation, and in most instances merely which are many of the theorems which transcribing Voss's words, so as to shew he afterwards developed in his Dialogues indisputably whence they derived their on Motion. These were not published account. Voss himself gives no authortill fifty years afterwards, and we shall ity, and his general inaccuracy makes reserve an account of their contents till his mere word not of much weight. we reach that period of his life.
The assertion appears, on many accounts, Galileo was by no means the first who destitute of much probability. If the had ventured to call in question the au- story were correct, it seems likely that thority of Aristotle in matters of science, some degree of acquaintance, if not of althcugh he was undoubtedly the first friendly intercourse, would have subwhrse opinions and writings produced a sisted between Mæstlin, and his supvery marked and general effect. Nizzoli, posed pupil, such as in fact we find a celebrated scholar who lived in the early subsisting between Mæstlin and his acpart of the 16th century, had condemned knowledged pupil Kepler, the devoted Juristotle's philosophy, especially his Phy- friend of Galileo; but, on the contrary, sics, in very unequivocal and forcible we find Mæstlin writing to Kepler himterms, declaring that, although there self of Galileo as an entire stranger, were many excellent truths in his wri- and in the most disparaging terms. If tings, the number was scarcely less of Mæstlin could lay claim to the honour of false, useless, and ridiculous proposi- so celebrated a disciple, it is not likely tions*. About the time of Galileo's that he could fail so entirely to comprebirth, Benedetti had written expressly hend the distinction it must confer upon in confutation of several propositions himself as to attempt diminishing it contained in Aristotle's mechanics, and by underrating his pupil's reputation. had expounded in a clear manner some There is a passage in Galileo's works of the doctrines of statical equilibrium.which more directly controverts the claim Within the last forty years it has been advanced for Mastlin, although Salusestablished that the celebrated painter bury, in his life of Galileo, having appaLeonardo da Vinci, who died in 1519, rently an imperfect recollection of its amused his leisure hours in scientific tenor, refers to this very passage in conpursuits; and many ideas appear to firmation of Voss's statement. In the have occurred to him which are to be second part of the dialogue on the Cofound in the writings of Galileo at a later pernican system, Galileo makes Sagredo, date. It is not impossible (though there one of the speakers in it, give the folare probably no means of directly ascer- lowing account:-“ Being very young, taining the fact) that Galileo may have and having scarcely finished my course been acquainted with Leonardo's inves of philosophy, which I left off as tigations, although they remained, till being set upon other employments, there very lately, almost unknown to the ma- chanced to come into these parts a certhematical world. This supposition is tain foreigner of Rostoch, whose name, rendered more probable from the fact, as I remember, was Christianus Urstia that Mazenta, the preserver of Leonardo's sius, a follower of Copernicus, who, in manuscripts, was, at the very time of an academy, gave two or three lectures • Antibarbarus Philosophicus. Francofurti, 16,4.
upon this point, to whom many flocked + Speculationum liber. Venetiis, 1585.
as auditors; but I, thinking they went