Nantes；　Queen　Elizabeth　had　defeated　the　Invincible　Armada；　and
  William　the　Silent　had　achieved　the　independence　of　Holland。
  Such　were　some　of　the　lights　and　some　of　the　enterprises　of　that
  great　age；　when　the　profoundest　questions　pertaining　to　philosophy；
  religion；　law；　and　government　were　discussed　with　the　enthusiasm
  and　freshness　of　a　revolutionary　age；　when　men　felt　the　inspiration
  of　a　new　life；　and　looked　back　on　the　Middle　Ages　with　disgust　and
  hatred；　as　a　period　which　enslaved　the　human　soul。　　But　what
  peculiarly　marked　that　period　was　the　commencement　of　those
  marvellous　discoveries　in　science　which　have　enriched　our　times　and
  added　to　the　material　blessings　of　the　new　civilization。　　Tycho
  Brahe；　Copernicus；　Galileo；　Kepler；　and　Bacon　inaugurated　the　era
  which　led　to　progressive　improvements　in　the　physical　condition　of
  society；　and　to　those　scientific　marvels　which　have　followed　in
  such　quick　succession　and　produced　such　astonishing　changes　that　we
  are　fain　to　boast　that　we　have　entered　upon　the　most　fortunate　and
  triumphant　epoch　in　our　world's　history。
  Many　men　might　be　taken　as　the　representatives　of　this　new　era　of
  science　and　material　inventions；　but　I　select　Galileo　Galilei　as
  one　of　the　most　interesting　in　his　life；　opinions；　and　conflicts。
  Galileo　was　born　at　Pisa；　in　the　year　1564；　the　year　that　Calvin
  and　Michael　Angelo　died；　four　years　after　the　birth　of　Bacon；　in
  the　sixth　year　of　the　reign　of　Elizabeth；　and　the　fourth　of　Charles
  IX。；　about　the　time　when　the　Huguenot　persecution　was　at　its
  height；　and　the　Spanish　monarchy　was　in　its　most　prosperous　state；
  under　Philip　II。　　His　parents　were　of　a　noble　but　impoverished
  Florentine　family；　and　his　father；　who　was　a　man　of　some　learning；
  a　writer　on　the　science　of　music；gave　him　the　best　education　he
  could　afford。　　Like　so　many　of　the　most　illustrious　men；　he　early
  gave　promise　of　rare　abilities。　　It　was　while　he　was　a　student　in
  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　hypot