beacon lights of history-iii-2-第71章

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the　university　of　his　native　city　that　his　attention　was　arrested

by　the　vibrations　of　a　lamp　suspended　from　the　ceiling　of　the

cathedral；　and　before　he　had　quitted　the　church；　while　the　choir

was　chanting　mediaeval　anthems；　he　had　compared　those　vibrations

with　his　own　pulse；　which　after　repeated　experiments；　ended　in　the

construction　of　the　first　pendulum；applied　not　as　it　was　by

Huygens　to　the　measurement　of　time；　but　to　medical　science；　to

enable　physicians　to　ascertain　the　rate　of　the　pulse。　　But　the

pendulum　was　soon　brought　into　the　service　of　the　clockmakers；　and

ultimately　to　the　determination　of　the　form　of　the　earth；　by　its

minute　irregularities　in　diverse　latitudes；　and　finally　to　the

measurement　of　differences　of　longitude　by　its　connection　with

electricity　and　the　recording　of　astronomical　observations。　　Thus

it　was　that　the　swinging　of　a　cathedral　lamp；　before　the　eye　of　a

man　of　genius；　has　done　nearly　as　much　as　the　telescope　itself　to

advance　science；　to　say　nothing　of　its　practical　uses　in　common

life。



Galileo　had　been　destined　by　his　father　to　the　profession　of

medicine；　and　was　ignorant　of　mathematics。　　He　amused　his　leisure

hours　with　painting　and　music；　and　in　order　to　study　the　principles

of　drawing　he　found　it　necessary　to　acquire　some　knowledge　of

geometry；　much　to　the　annoyance　of　his　father；　who　did　not　like　to

see　his　mind　diverted　from　the　prescriptions　of　Hippocrates　and

Galen。　　The　certain　truths　of　geometry　burst　upon　him　like　a

revelation；　and　after　mastering　Euclid　he　turned　to　Archimedes　with

equal　enthusiasm。　　Mathematics　now　absorbed　his　mind；　and　the

father　was　obliged　to　yield　to　the　bent　of　his　genius；　which　seemed

to　disdain　the　regular　professions　by　which　social　position　was

most　surely　effected。　　He　wrote　about　this　time　an　essay　on　the

Hydrostatic　Balance；　which　introduced　him　to　Guido　Ubaldo；　a　famous

mathematician；　who　induced　him　to　investigate　the　subject　of　the

centre　of　gravity　in　solid　bodies。　　His　treatise　on　this　subject

secured　an　introduction　to　the　Grand　Duke　of　Tuscany；　who　perceived

his　merits；　and　by　whom　he　was　appointed　a　lecturer　on　mathematics

at　Pisa；　but　on　the　small　salary　of　sixty　crowns　a　year。



This　was　in　1589；　when　he　was　twenty…five；　an　enthusiastic　young

man；　full　of　hope　and　animal　spirits；　the　charm　of　every　circle　for

his　intelligence；　vivacity；　and　wit；　but　bold　and　sarcastic；

contemptuous　of　ancient　dogmas；　defiant　of　authority；　and　therefore

no　favorite　with　Jesuit　priests　and　Dominican　professors。　　It　is

said　that　he　was　a　handsome　man；　with　bright　golden　locks；　such　as

painters　in　that　age　loved　to　perpetuate　upon　the　canvas；　hilarious

and　cheerful；　fond　of　good　cheer；　yet　a　close　student；　obnoxious

only　to　learned　dunces　and　narrow　pedants　and　treadmill　professors

and　zealous　priests；all　of　whom　sought　to　molest　him；　yet　to　whom

he　was　either　indifferent　or　sarcastic；　holding　them　and　their

formulas　up　to　ridicule。　　He　now　directed　his　inquiries　to　the

mechanical　doctrines　of　Aristotle；　to　whose　authority　the　schools

had　long　bowed　down；　and　whom　he　too　regarded　as　one　of　the　great

intellectual　giants　of　the　world；　yet　not　to　be　credited　without

sufficient　reasons。　　Before　the　〃Novum　Organum〃　was　written；　he

sought；　as　Bacon　himself　pointed　out；　the　way　to　arrive　at　truth；

a　foundation　to　stand　upon；　a　principle　tested　by　experience；

which；　when　established　by　experiment；　would　serve　for　sure

deductions。



Now　one　of　the　principles　assumed　by　Aristotle；　and　which　had　never

been　disputed；　was；　that　if　different　weights　of　the　same　material

were　let　fall　from　the　same　height；　the　heavier　would　reach　the

ground　sooner　than　the　lighter；　and　in　proportion　to　the　difference

of　weight。　　This　assumption　Galileo　denied；　and　asserted　that；　with

the　exception　of　a　small　difference　owing　to　the　resistance　of　the

air；　both　would　fall　to　the　ground　in　the　same　space　of　time。　　To

prove　his　position　by　actual　experiment；　he　repaired　to　the　leaning

tower　of　Pisa；　and　demonstrated　that　he　was　right　and　Aristotle　was

wrong。　　The　Aristotelians　would　not　believe　the　evidence　of　their

own　senses；　and　ascribed　the　effect　to　some　unknown　cause。　　To　such

a　degree　were　men　enslaved　by　authority。　　This　provoked　Galileo；

and　led　him　to　attack　authority　with　still　greater　vehemence；

adding　mockery　to　sarcasm；　which　again　exasperated　his　opponents；

and　doubtless　laid　the　foundation　of　that　personal　hostility　which

afterwards　pursued　him　to　the　prison　of　the　Inquisition。　　This

blended　arrogance　and　asperity　in　a　young　man　was　offensive　to　the

whole　university；　yet　natural　to　one　who　had　overturned　one　of　the

favorite　axioms　of　the　greatest　master　of　thought　the　world　had

seen　for　nearly　two　thousand　years；　and　the　scorn　and　opposition

with　which　his　discovery　was　received　increased　his　rancor；　so　that

he；　in　his　turn；　did　not　render　justice　to　the　learned　men　arrayed

against　him；　who　were　not　necessarily　dull　or　obstinate　because

they　would　not　at　once　give　up　the　opinions　in　which　they　were

educated；　and　which　the　learned　world　still　accepted。　　Nor　did　they

oppose　and　hate　him　for　his　new　opinions；　so　much　as　from　dislike

of　his　personal　arrogance　and　bitter　sarcasms。



At　last　his　enemies　made　it　too　hot　for　him　at　Pisa。　　He　resigned

his　chair　（1591）；　but　only　to　accept　a　higher　position　at　Padua；　on

a　salary　of　one　hundred　and　eighty　florins；not；　however；　adequate

to　his　support；　so　that　he　was　obliged　to　take　pupils　in

mathematics。　　To　show　the　comparative　estimate　of　that　age　of

science；　the　fact　may　be　mentioned　that　the　professor　of　scholastic

philosophy　in　the　same　university　was　paid　fourteen　hundred

florins。　　This　was　in　1592；　and　the　next　year　Galileo　invented　the

thermometer；　still　an　imperfect　instrument；　since　air　was　not

perfectly　excluded。　　At　this　period　his　reputation　seems　to　have

been　established　as　a　brilliant　lecturer　rather　than　as　a　great

discoverer；　or　even　as　a　great　mathematician；　for　he　was

immeasurably　behind　Kepler；　his　contemporary；　in　the　power　of

making　abstruse　calculations　and　numerical　combinations。　　In　this

respect　Kepler　was　inferior　only　to　Copernicus；　Newton；　and　Laplace

in　our　times；　or　Hipparchus　and　Ptolemy　among　the　ancients；　and　it

is　to　him　that　we　owe　the　discovery　of　those　great　laws　of

planetary　motion　from　which　there　is　no　appeal；　and　which　have

never　been　rivalled　in　importance　except　those　made　by　Newton

himself；laws　which　connect　the　mean　distance　of　the　planets　from

the　sun　with　the　times　of　their　revolutions；　laws　which　show　that

the　orbits　of　planets　are　elliptical；　not　circular；　and　that　the

areas　described　by　lines　drawn　from　the　moving　planet　to　the　sun

are　proportionable　to　the　times　employed　in　the　motion。　　What　an

infinity　of　calculation；　in　the　infancy　of　sciencebefore　the

invention　of　logarithms；was　necessary　to　arrive　at　these　truths！

What　fertility　of　invention　was　displayed　in　all　his　hypotheses；

what　patience　in　working　them　out；　what　magnanimity　in　discarding

those　which　were　not　true！　　What　power　of　guessing；　even　to　hit

upon　theories　which　could　be　established　by　elaborate

calculations；all　from　the　primary　thought；　the　grand　axiom；　which

Kepler　was　the　first　to　propose；　that　there　must　be　some　numerical

or　geometrical　relations　among　the　times；　distances；　and　velocities

of　the　revolving　bodies　of　the　solar　system！　　It　would　seem　that

although　his　science　was　deductive；　he　invoked　the　aid　of　induction

also：　a　great　original　genius；　yet　modest　like　Newton；　a　man　who

avoided　hostilities；　yet　given　to　the　most　boundless　enthusiasm　on

the　subjects　to　which　he　devoted　his　life。　　How　intense　his

raptures！　　〃Nothing　holds　me；〃　he　writes；　on　discovering　his　great

laws；　〃I　will　indulge　in　my　sacred　fury。　　I　will　boast　of　the

golden　vessels　I　have　stolen　from　the　Egyptians。　　If　you　forgive

me；　I　rejoice。　　If　you　are　angry；　it　is　all　the　same　to　me。