turned　rapidly　on　its　hinges；　and　Satellite　was　thrown　out。
  Scarcely　a　particle　of　air　could　have　escaped；　and　the　operation
  was　so　successful　that　later　on　Barbicane　did　not　fear　to
  dispose　of　the　rubbish　which　encumbered　the　car。
  CHAPTER　VI
  QUESTION　AND　ANSWER
  On　the　4th　of　December；　when　the　travelers　awoke　after
  fifty…four　hours'　journey；　the　chronometer　marked　five　o'clock
  of　the　terrestrial　morning。　　In　time　it　was　just　over　five
  hours　and　forty　minutes；　half　of　that　assigned　to　their　sojourn
  in　the　projectile；　but　they　had　already　accomplished　nearly
  seven…tenths　of　the　way。　　This　peculiarity　was　due　to　their
  regularly　decreasing　speed。
  Now　when　they　observed　the　earth　through　the　lower　window；
  it　looked　like　nothing　more　than　a　dark　spot；　drowned　in　the
  solar　rays。　　No　more　crescent；　no　more　cloudy　light！　　The　next
  day；　at　midnight；　the　earth　would　be　_new_；　at　the　very　moment
  when　the　moon　would　be　full。　　Above；　the　orb　of　night　was　nearing
  the　line　followed　by　the　projectile；　so　as　to　meet　it　at　the
  given　hour。　　All　around　the　black　vault　was　studded　with　brilliant
  points；　which　seemed　to　move　slowly；　but；　at　the　great　distance
  they　were　from　them；　their　relative　size　did　not　seem　to　change。
  The　sun　and　stars　appeared　exactly　as　they　do　to　us　upon　earth。
  As　to　the　moon；　she　was　considerably　larger；　but　the　travelers'
  glasses；　not　very　powerful；　did　not　allow　them　as　yet　to　make
  any　useful　observations　upon　her　surface；　or　reconnoiter　her
  topographically　or　geologically。
  Thus　the　time　passed　in　never…ending　conversations　all　about
  the　moon。　　Each　one　brought　forward　his　own　contingent　of
  particular　facts；　Barbicane　and　Nicholl　always　serious；　Michel
  Ardan　always　enthusiastic。　　The　projectile；　its　situation；
  its　direction；　incidents　which　might　happen；　the　precautions
  necessitated　by　their　fall　on　to　the　moon；　were　inexhaustible
  matters　of　conjecture。
  As　they　were　breakfasting；　a　question　of　Michel's；　relating　to
  the　projectile；　provoked　rather　a　curious　answer　from　Barbicane；
  which　is　worth　repeating。　　Michel；　supposing　it　to　be　roughly
  stopped；　while　still　under　its　formidable　initial　speed；　wished
  to　know　what　the　consequences　of　the　stoppage　would　have　been。
  〃But；〃　said　Barbicane；　〃I　do　not　see　how　it　could　have　been　stopped。〃
  〃But　let　us　suppose　so；〃　said　Michel。
  〃It　is　an　impossible　supposition；〃　said　the　practical　Barbicane；
  〃unless　that　impulsive　force　had　failed；　but　even　then　its　speed
  would　diminish　by　degrees；　and　it　would　not　have　stopped　suddenly。〃
  〃Admit　that　it　had　struck　a　body　in　space。〃
  〃What　body？〃
  〃Why　that　enormous　meteor　which　we　met。〃
  〃Then；〃　said　Nicholl；　〃the　projectile　would　have　been　broken
  into　a　thousand　pieces；　and　we　with　it。〃
  〃More　than　that；〃　replied　Barbicane；　〃we　should　have　been　burned
  to　death。〃
  〃Burned？〃　exclaimed　Michel；　〃by　Jove！　　I　am　sorry　it　did　not
  happen；　‘just　to　see。'〃
  〃And　you　would　have　seen；〃　replied　Barbicane。　　〃It　is　known　now
  that　heat　is　only　a　modification　of　motion。　　When　water　is
  warmed　that　is　to　say；　when　heat　is　added　to　itits　particles
  are　set　in　motion。〃
  〃Well；〃　said　michel；　〃that　is　an　ingenious　theory！〃
  〃And　a　true　one；　my　worthy　friend；　for　it　explains　every
  phenomenon　of　caloric。　　Heat　is　but　the　motion　of　atoms；　a
  simple　oscillation　of　the　particles　of　a　body。　　When　they　apply
  the　brake　to　a　train；　the　train　comes　to　a　stop；　but　what
  becomes　of　the　motion　which　it　had　previously　possessed？　　It　is
  transformed　into　heat；　and　the　brake　becomes　hot。　　Why　do　they
  grease　the　axles　of　the　wheels？　　To　prevent　their　heating；
  because　this　heat　would　be　generated　by　the　motion　which　is　thus
  lost　by　transformation。〃
  〃Yes；　I　understand；〃　replied　Michel；　〃perfectly。　　For　example；
  when　I　have　run　a　long　time；　when　I　am　swimming；　when　I　am
  perspiring　in　large　drops；　why　am　I　obliged　to　stop？
  Simply　because　my　motion　is　changed　into　heat。〃
  Barbicane　could　not　help　smiling　at　Michel's　reply；　then；
  returning　to　his　theory；　said：
  〃Thus；　in　case　of　a　shock；　it　would　have　been　with　our
  projectile　as　with　a　ball　which　falls　in　a　burning　state　after
  having　struck　the　metal　plate；　it　is　its　motion　which　is　turned
  into　heat。　　Consequently　I　affirm　that；　if　our　projectile　had
  struck　the　meteor；　its　speed　thus　suddenly　checked　would　have
  raised　a　heat　great　enough　to　turn　it　into　vapor　instantaneously。〃
  〃Then；〃　asked　Nicholl；　〃what　would　happen　if　the　earth's　motion
  were　to　stop　suddenly？〃
  〃Her　temperature　would　be　raised　to　such　a　pitch；〃　said
  Barbicane；　〃that　she　would　be　at　once　reduced　to　vapor。〃
  〃Well；〃　said　Michel；　〃that　is　a　way　of　ending　the　earth　which
  will　greatly　simplify　things。〃
  〃And　if　the　earth　fell　upon　the　sun？〃　asked　Nicholl。
  〃According　to　calculation；〃　replied　Barbicane；　〃the　fall　would
  develop　a　heat　equal　to　that　produced　by　16；000　globes　of　coal；
  each　equal　in　bulk　to　our　terrestrial　globe。〃
  〃Good　additional　heat　for　the　sun；〃　replied　Michel　Ardan；　〃of
  which　the　inhabitants　of　Uranus　or　Neptune　would　doubtless　not
  complain；　they　must　be　perished　with　cold　on　their　planets。〃
  〃Thus；　my　friends；〃　said　Barbicane；　〃all　motion　suddenly　stopped
  produces　heat。　　And　this　theory　allows　us　to　infer　that　the　heat
  of　the　solar　disc　is　fed　by　a　hail　of　meteors　falling
  incessantly　on　its　surface。　　They　have　even　calculated〃
  〃Oh；　dear！〃　murmured　Michel；　〃the　figures　are　coming。〃
  〃They　have　even　calculated；〃　continued　the　imperturbable　Barbicane；
  〃that　the　shock　of　each　meteor　on　the　sun　ought　to　produce　a　heat
  equal　to　that　of　4；000　masses　of　coal　of　an　equal　bulk。〃
  〃And　what　is　the　solar　heat？〃　asked　Michel。
  〃It　is　equal　to　that　produced　by　the　combustion　of　a　stratum　of
  coal　surrounding　the　sun　to　a　depth　of　forty…seven　miles。〃
  〃And　that　heat〃
  〃Would　be　able　to　boil　two　billions　nine　hundred　millions　of
  cubic　myriameters　＇2＇　of　water。〃
  ＇2＇　The　myriameter　is　equal　to　rather　more　than　10；936
  cubic　yards　English。
  〃And　it　does　not　roast　us！〃　exclaimed　Michel。
  〃No；〃　replied　Barbicane；　〃because　the　terrestrial　atmosphere
  absorbs　four…tenths　of　the　solar　heat；　besides；　the　quantity　of
  heat　intercepted　by　the　earth　is　but　a　billionth　part　of　the
  entire　radiation。〃
  〃I　see　that　all　is　for　the　best；〃　said　Michel；　〃and　that　this
  atmosphere　is　a　useful　invention；　for　it　not　only　allows　us　to
  breathe；　but　it　prevents　us　from　roasting。〃
  〃Yes！〃　said　Nicholl；　〃unfortunately；　it　will　not　be　the　same　in
  the　moon。〃
  〃Bah！〃　said　Michel；　always　hopeful。　　〃If　there　are　inhabitants；
  they　must　breathe。　　If　there　are　no　longer　any；　they　must　have
  left　enough　oxygen　for　three　people；　if　only　at　the　bottom　of
  ravines；　where　its　own　weight　will　cause　it　to　accumulate；　and
  we　will　not　climb　the　mountains；　that　is　all。〃　　And　Michel；
  rising；　went　to　look　at　the　lunar　disc；　which　shone　with
  intolerable　brilliancy。
  〃By　Jove！〃　said　he；　〃it　must　be　hot　up　there！〃
  〃Without　considering；〃　replied　Nicholl；　〃that　the　day　lasts　360　hours！〃
  〃And　to　compensate　that；〃　said　Barbicane；　〃the　nights　have　the
  same　length；　and　as　heat　is　restored　by　radiation；　their
  temperature　can　only　be　that　of　the　planetary　space。〃
  〃A　pretty　country；　that！〃　exclaimed　Michel。　　〃Never　mind！
  I　wish　I　was　there！　　Ah！　my　dear　comrades；　it　will　be　rather
  curious　to　have　the　earth　for　our　moon；　to　see　it　rise　on　the
  horizon；　to　recognize　the　shape　of　its　continents；　and　to　say
  to　oneself；　‘There　is　America；　there　is　Europe；'　then　to　follow
  it　when　it　is　about　to　lose　itself　in　the　sun's　rays！　　By　the
  bye；　Barbicane；　have　the　Selenites　eclipses？〃
  〃Yes；　eclipses　of　the　sun；〃　replied　Barbicane；　〃when　the　centers
  of　the　three　orbs　are　on　a　line；　the　earth　being　in　the　middle。
  But　they　are　only　partial；　during　which　the　earth；　cast　like　a
  screen　upon　the　solar　disc；　allows　the　greater　portion　to　be　seen。〃
  〃And　why；〃　asked　Nicholl；　〃is　there　no　total　eclipse？　　Does　not
  the　cone　of　the　shadow　cast　by　the　earth　extend　beyond　the　moon？〃
  〃Yes；　if　we　do　not　take　into　consideration　the　refraction
  produced　by　the　terrestrial　atmosphere。　　No；　if　we　take　that
  refraction　into　consideration。　　Thus　let　　be
  the　horizontal　parallel；　and　_p_　the　apparent　semidiameter〃
  〃Oh！〃　said　Michel。　　〃Do　speak　plainly；　you　man　of　algebra！〃
  〃Very　well；　replied　Barbicane；　〃in　popular　language　the　mean
  distance　from　the　moon　to　the　earth　being　sixty　terrestrial
  radii；　the　length　of　the　cone　of　the　shadow；　on　account　of
  refraction；　is　reduced　to　less　than　forty…two　radii。
  The　result　is　that　when　there　are　eclipses；　the　moon　finds
  itself　beyond　the　cone　of　pure　shadow；　and　that　the　sun　sends
  her　its　rays；　not　only　from　its　edges；　but　also　from　its　center。〃
  〃Then；〃　said　Michel；　in　a　merry　tone；　〃why　are　there　eclipses；
  when　there　ought　not　to　be　any？〃
  〃Simply　because　the　solar　rays　are　weakened　by　this　refraction；
  and　the　atmosphere　through　which　they　pass　extinguished　the
  greater　part　of　them！〃
  〃That　reason　satisfies　me；〃　replied　Michel。　　〃Besides　we　shall
  see　when　we　get　there。　　Now；　tell　me；　Barbicane；　do　you　believe
  that　the　moon　is　an　old　comet？〃
  〃There's　an　idea！〃
  〃Yes；〃　replied　Michel；　with