retend　to　reason　retrospectively　from　the　nineteenth　to　the　fourteenth　century；　but　if　we　take　a　general　view　of　the　occurrences；　that　century　will　give　us　copious　information；　and；　as　applicable　to　all　succeeding　times；　of　high　importance。
  In　the　progress　of　connected　natural　phenomena　from　east　to　west；　that　great　law　of　nature　is　plainly　revealed　which　has　so　often　and　evidently　manifested　itself　in　the　earth's　organism；　as　well　as　in　the　state　of　nations　dependent　upon　it。　　In　the　inmost　depths　of　the　globe　that　impulse　was　given　in　the　year　1333；　which　in　uninterrupted　succession　for　six　and　twenty　years　shook　the　surface　of　the　earth；　even　to　the　western　shores　of　Europe。　　From　the　very　beginning　the　air　partook　of　the　terrestrial　concussion；　atmospherical　waters　overflowed　the　land；　or　its　plants　and　animals　perished　under　the　scorching　heat。　　The　insect　tribe　was　wonderfully　called　into　life；　as　if　animated　beings　were　destined　to　complete　the　destruction　which　astral　and　telluric　powers　had　begun。　　Thus　did　this　dreadful　work　of　nature　advance　from　year　to　year；　it　was　a　progressive　infection　of　the　zones；　which　exerted　a　powerful　influence　both　above　and　beneath　the　surface　of　the　earth；　and　after　having　been　perceptible　in　slighter　indications；　at　the　commencement　of　the　terrestrial　commotions　in　China；　convulsed　the　whole　earth。
  The　nature　of　the　first　plague　in　China　is　unknown。　　We　have　no　certain　intelligence　of　the　disease　until　it　entered　the　western　countries　of　Asia。　　Here　it　showed　itself　as　the　Oriental　plague；　with　inflammation　of　the　lungs；　in　which　form　it　probably　also　may　have　begun　in　China；　that　is　to　say；　as　a　malady　which　spreads；　more　than　any　other；　by　contagiona　contagion　that；　in　ordinary　pestilences；　requires　immediate　contact；　and　only　under　favourable　circumstances　of　rare　occurrence　is　communicated　by　the　mere　approach　to　the　sick。　　The　share　which　this　cause　had　in　the　spreading　of　the　plague　over　the　whole　earth　was　certainly　very　great；　and　the　opinion　that　the　Black　Death　might　have　been　excluded　from　Western　Europe　by　good　regulations；　similar　to　those　which　are　now　in　use；　would　have　all　the　support　of　modern　experience；　provided　it　could　be　proved　that　this　plague　had　been　actually　imported　from　the　East；　or　that　the　Oriental　plague　in　general；　whenever　it　appears　in　Europe；　has　its　origin　in　Asia　or　Egypt。　　Such　a　proof；　however；　can　by　no　means　be　produced　so　as　to　enforce　conviction；　for　it　would　involve　the　impossible　assumption；　either　that　there　is　no　essential　difference　between　the　degree　of　civilisation　of　the　European　nations；　in　the　most　ancient　and　in　modern　times；　or　that　detrimental　circumstances；　which　have　yielded　only　to　the　civilisation　of　human　society　and　the　regular　cultivation　of　countries；　could　not　formerly　keep　up　the　glandular　plague。
  The　plague　was；　however；　known　in　Europe　before　nations　were　united　by　the　bonds　of　commerce　and　social　intercourse；　hence　there　is　ground　for　supposing　that　it　sprang　up　spontaneously；　in　consequence　of　the　rude　manner　of　living　and　the　uncultivated　state　of　the　earth；　influences　which　peculiarly　favour　the　origin　of　severe　diseases。　　Now　we　need　not　go　back　to　the　earlier　centuries；　for　the　fourteenth　itself；　before　it　had　half　expired；　was　visited　by　five　or　six　pestilences。
  If；　therefore；　we　consider　the　peculiar　property　of　the　plague；　that　in　countries　which　it　has　once　visited　it　remains　for　a　long　time　in　a　milder　form；　and　that　the　epidemic　influences　of　1342；　when　it　had　appeared　for　the　last　time；　were　particularly　favourable　to　its　unperceived　continuance；　till　1348；　we　come　to　the　notion　that　in　this　eventful　year　also　the　germs　of　plague　existed　in　Southern　Europe；　which　might　be　vivified　by　atmospherical　deteriorations；　and　that　thus；　at　least　in　part；　the　Black　Plague　may　have　originated　in　Europe　itself。　　The　corruption　of　the　atmosphere　came　from　the　East；　but　the　disease　itself　came　not　upon　the　wings　of　the　wind；　but　was　only　excited　and　increased　by　the　atmosphere　where　it　had　previously　existed。
  This　source　of　the　Black　Plague　was　not；　however；　the　only　one；　for　far　more　powerful　than　the　excitement　of　the　latent　elements　of　the　plague　by　atmospheric　influences　was　the　effect　of　the　contagion　communicated　from　one　people　to　another　on　the　great　roads　and　in　the　harbours　of　the　Mediterranean。　　From　China　the　route　of　the　caravans　lay　to　the　north　of　the　Caspian　Sea；　through　Central　Asia；　to　Tauris。　　Here　ships　were　ready　to　take　the　produce　of　the　East　to　Constantinople；　the　capital　of　commerce；　and　the　medium　of　connection　between　Asia；　Europe；　and　Africa。　Other　caravans　went　from　India　to　Asia　Minor；　and　touched　at　the　cities　south　of　the　Caspian　Sea；　and；　lastly；　from　Bagdad　through　Arabia　to　Egypt；　also　the　maritime　communication　on　the　Red　Sea；　from　India　to　Arabia　and　Egypt；　was　not　inconsiderable。　　In　all　these　directions　contagion　made　its　way；　and；　doubtless；　Constantinople　and　the　harbours　of　Asia　Minor　are　to　be　regarded　as　the　foci　of　infection；　whence　it　radiated　to　the　most　distant　seaports　and　islands。
  To　Constantinople　the　plague　had　been　brought　from　the　northern　coast　of　the　Black　Sea；　after　it　had　depopulated　the　countries　between　those　routes　of　commerce；　and　appeared　as　early　as　1347　in　Cyprus；　Sicily；　Marseilles；　and　some　of　the　seaports　of　Italy。　The　remaining　islands　of　the　Mediterranean；　particularly　Sardinia；　Corsica；　and　Majorca；　were　visited　in　succession。　　Foci　of　contagion　existed　also　in　full　activity　along　the　whole　southern　coast　of　Europe；　when；　in　January；　1348；　the　plague　appeared　in　Avignon；　and　in　other　cities　in　the　south　of　France　and　north　of　Italy；　as　well　as　in　Spain。
  The　precise　days　of　its　eruption　in　the　individual　towns　are　no　longer　to　be　ascertained；　but　it　was　not　simultaneous；　for　in　Florence　the　disease　appeared　in　the　beginning　of　April；　in　Cesena　the　1st　June；　and　place　after　place　was　attacked　throughout　the　whole　year；　so　that　the　plague；　after　it　had　passed　through　the　whole　of　France　and　Germanywhere；　however；　it　did　not　make　its　ravages　until　the　following　yeardid　not　break　out　till　August　in　England；　where　it　advanced　so　gradually；　that　a　period　of　three　months　elapsed　before　it　reached　London。　　The　northern　kingdoms　were　attacked　by　it　in　1349；　Sweden；　indeed；　not　until　November　of　that　year；　almost　two　years　after　its　eruption　in　Avignon。　　Poland　received　the　plague　in　1349；　probably　from　Germany；　if　not　from　the　northern　countries；　but　in　Russia　it　did　not　make　its　appearance　until　1351；　more　than　three　years　after　it　had　broken　out　in　Constantinople。　　Instead　of　advancing　in　a　north…westerly　direction　from　Tauris　and　from　the　Caspian　Sea；　it　had　thus　made　the　great　circuit　of　the　Black　Sea；　by　way　of　Constantinople；　Southern　and　Central　Europe；　England；　the　northern　kingdoms；　and　Poland；　before　it　reached　the　Russian　territories；　a　phenomenon　which　has　not　again　occurred　with　respect　to　more　recent　pestilences　originating　in　Asia。
  Whether　any　difference　existed　between　the　indigenous　plague；　excited　by　the　influence　of　the　atmosphere；　and　that　which　was　imported　by　contagion；　can　no　longer　be　ascertained　from　facts；　for　the　contemporaries；　who　in　general　were　not　competent　to　make　accurate　researches　of　this　kind；　have　left　no　data　on　the　subject。　　A　milder　and　a　more　malignant　form　certainly　existed；　and　the　former　was　not　always　derived　from　the　latter；　as　is　to　be　supposed　from　this　circumstancethat　the　spitting　of　blood；　the　infallible　diagnostic　of　the　latter；　on　the　first　breaking　out　of　the　plague；　is　not　similarly　mentioned　in　all　the　reports；　and　it　is　therefore　probable　that　the　milder　form　belonged　to　the　native　plaguethe　more　malignant；　to　that　introduced　by　contagion。　Contagion　was；　however；　in　itself；　only　one　of　many　causes　which　gave　rise　to　the　Black　Plague。
  This　disease　was　a　consequence　of　violent　commotions　in　the　earth's　organismif　any　disease　of　cosmical　origin　can　be　so　considered。　　One　spring　set　a　thousand　others　in　motion　for　the　annihilation　of　living　beings；　transient　or　permanent；　of　mediate　or　immediate　effect。　　The　most　powerful　of　all　was　contagion；　for　in　the　most　distant　countries；　which　had　scarcely　yet　heard　the　echo　of　the　first　concussion；　the　people　fell　a　sacrifice　to　organic　poisonthe　untimely　offspring　of　vital　energies　thrown　into　violent　commotion。
  CHAPTER　IVMORTALITY
  We　have　no　certain　measure　by　which　to　estimate　the　ravages　of　the　Black　Plague；　if　numerical　statements　were　wanted；　as　in　modern　times。　　Let　us　go　back　for　a　moment　to　the　fourteenth　century。　The　people　were　yet　but　little　civilised。　　The　Church　had　indeed　subdued　them；　but　they　all　suffered　from　the　ill　consequences　of　their　original　rudeness。　　The　dominion　of　the　law　was　not　yet　confirmed。　　Sovereigns　had　everywhere　to　combat　powerful　enemies　to　internal　tranquillity　and　security。　　The　cities　were　fortresses　for　their　own　defence。　　Marauders　encamped　on　the　roads。　　The　husbandman　was　a　feudal　slave；　without　possessions　of　his　own。　Rudeness　was　general；　humanity　as　yet　unknown　to　the　people。　Witches　and　heretics　were　burned　alive。　　Gentle　rulers　were　contemned　as　weak；　wild　passions；　severity　and　cruelty；