the underground city- 第7部分

〃So　we　are　going　to　the　end　of　the　last　vein？〃　said　James　Starr。


〃Ay！　　You　know　the　mine　well　still。〃

〃Well；　Simon；〃　returned　the　engineer；　〃it　will　be　difficult　to　go　further　than　that；　if　I　don't　mistake。〃

〃Yes；　indeed；　Mr。　Starr。　　That　was　where　our　picks　tore　out　the　last　bit　of　coal　in　the　seam。　　I　remember　it　as　if　it　were　yesterday。　I　myself　gave　that　last　blow；　and　it　re…echoed　in　my　heart　more　dismally　than　on　the　rock。　　Only　sandstone　and　schist　were　round　us　after　that；　and　when　the　truck　rolled　towards　the　shaft；　I　followed；　with　my　heart　as　full　as　though　it　were　a　funeral。　It　seemed　to　me　that　the　soul　of　the　mine　was　going　with　it。〃

The　gravity　with　which　the　old　man　uttered　these　words　impressed　the　engineer；　who　was　not　far　from　sharing　his　sentiments。　They　were　those　of　the　sailor　who　leaves　his　disabled　vessel　of　the　proprietor　who　sees　the　house　of　his　ancestors　pulled　down。　He　pressed　Ford's　hand；　but　now　the　latter　seized　that　of　the　engineer；　and；　wringing　it：

〃That　day　we　were　all　of　us　mistaken；〃　he　exclaimed。　　〃No！　　The　old　mine　was　not　dead。　　It　was　not　a　corpse　that　the　miners　abandoned；　and　I　dare　to　assert；　Mr。　Starr；　that　its　heart　beats　still。〃

〃Speak；　Ford！　　Have　you　discovered　a　new　vein？〃　cried　the　engineer；　unable　to　contain　himself。　　〃I　know　you　have！　　Your　letter　could　mean　nothing　else。〃

〃Mr。　Starr；〃　said　Simon　Ford；　〃I　did　not　wish　to　tell　any　man　but　yourself。〃

〃And　you　did　quite　right；　Ford。　　But　tell　me　how；　by　what　signs；　are　you　sure？〃

〃Listen；　sir！〃　resumed　Simon。　　〃It　is　not　a　seam　that　I　have　found。〃

〃What　is　it；　then？〃

〃Only　positive　proof　that　such　a　seam　exists。〃

〃And　the　proof？〃

〃Could　fire…damp　issue　from　the　bowels　of　the　earth　if　coal　was　not　there　to　produce　it？〃

〃No；　certainly　not！〃　replied　the　engineer。　　〃No　coal；　no　fire…damp。　No　effects　without　a　cause。〃

〃Just　as　no　smoke　without　fire。〃

〃And　have　you　recognized　the　presence　of　light　carburetted　hydrogen？〃

〃An　old　miner　could　not　be　deceived；〃　answered　Ford。　　〃I　have　met　with　our　old　enemy；　the　fire…damp！〃


〃But　suppose　it　was　another　gas；〃　said　Starr。　　〃Firedamp　is　almost　without　smell；　and　colorless。　　It　only　really　betrays　its　presence　by　an　explosion。〃

〃Mr。　Starr；〃　said　Simon　Ford；　〃will　you　let　me　tell　you　what　I　have　done？　　Harry　had　once　or　twice　observed　something　remarkable　in　his　excursions　to　the　west　end　of　the　mine。　Fire；　which　suddenly　went　out；　sometimes　appeared　along　the　face　of　the　rock　or　on　the　embankment　of　the　further　galleries。　How　those　flames　were　lighted；　I　could　not　and　cannot　say。　But　they　were　evidently　owing　to　the　presence　of　fire…damp；　and　to　me　fire…damp　means　a　vein　of　coal。〃

〃Did　not　these　fires　cause　any　explosion？〃　asked　the　engineer　quickly。

〃Yes；　little　partial　explosions；〃　replied　Ford；　〃such　as　I　used　to　cause　myself　when　I　wished　to　ascertain　the　presence　of　fire…damp。　Do　you　remember　how　formerly　it　was　the　custom　to　try　to　prevent　explosions　before　our　good　genius；　Humphry　Davy；　invented　his　safety…lamp？〃

〃Yes；〃　replied　James　Starr。　　〃You　mean　what　the　'monk；'　as　the　men　called　him；　used　to　do。　　But　I　have　never　seen　him　in　the　exercise　of　his　duty。〃

〃Indeed；　Mr。　Starr；　you　are　too　young；　in　spite　of　your　five…and…fifty　years；　to　have　seen　that。　　But　I；　ten　years　older；　often　saw　the　last　'monk'　working　in　the　mine。　He　was　called　so　because　he　wore　a　long　robe　like　a　monk。　His　proper　name　was　the　'fireman。'　　At　that　time　there　was　no　other　means　of　destroying　the　bad　gas　but　by　dispersing　it　in　little　explosions；　before　its　buoyancy　had　collected　it　in　too　great　quantities　in　the　heights　of　the　galleries。　The　monk；　as　we　called　him；　with　his　face　masked；　his　head　muffled　up；　all　his　body　tightly　wrapped　in　a　thick　felt　cloak；　crawled　along　the　ground。　　He　could　breathe　down　there；　when　the　air　was　pure；　and　with　his　right　hand　he　waved　above　his　head　a　blazing　torch。　When　the　firedamp　had　accumulated　in　the　air；　so　as　to　form　a　detonating　mixture；　the　explosion　occurred　without　being　fatal；　and；　by　often　renewing　this　operation；　catastrophes　were　prevented。　Sometimes　the　'monk'　was　injured　or　killed　in　his　work；　then　another　took　his　place。　　This　was　done　in　all　mines　until　the　Davy　lamp　was　universally　adopted。　　But　I　knew　the　plan；　and　by　its　means　I　discovered　the　presence　of　firedamp　and　consequently　that　of　a　new　seam　of　coal　in　the　Dochart　pit。〃

All　that　the　old　overman　had　related　of　the　so…called　〃monk〃　or　〃fireman〃　was　perfectly　true。　　The　air　in　the　galleries　of　mines　was　formerly　always　purified　in　the　way　described。

Fire…damp；　marsh…gas；　or　carburetted　hydrogen；　is　colorless；　almost　scentless；　it　burns　with　a　blue　flame；　and　makes　respiration　impossible。　　The　miner　could　not　live　in　a　place　filled　with　this　injurious　gas；　any　more　than　one　could　live　in　a　gasometer　full　of　common　gas。　　Moreover；　fire…damp；　as　well　as　the　latter；　a　mixture　of　inflammable　gases；　forms　a　detonating　mixture　as　soon　as　the　air　unites　with　it　in　a　proportion　of　eight；　and　perhaps　even　five　to　the　hundred。　When　this　mixture　is　lighted　by　any　cause；　there　is　an　explosion；　almost　always　followed　by　a　frightful　catastrophe。

As　they　walked　on；　Simon　Ford　told　the　engineer　all　that　he　had　done　to　attain　his　object；　how　he　was　sure　that　the　escape　of　fire…damp　took　place　at　the　very　end　of　the　farthest　gallery　in　its　western　part；　because　he　had　provoked　small　and　partial　explosions；　or　rather　little　flames；　enough　to　show　the　nature　of　the　gas；　which　escaped　in　a　small　jet；　but　with　a　continuous　flow。

An　hour　after　leaving　the　cottage；　James　Starr　and　his　two　companions　had　gone　a　distance　of　four　miles。　　The　engineer；　urged　by　anxiety　and　hope；　walked　on　without　noticing　the　length　of　the　way。　He　pondered　over　all　that　the　old　miner　had　told　him；　and　mentally　weighed　all　the　arguments　which　the　latter　had　given　in　support　of　his　belief。　He　agreed　with　him　in　thinking　that　the　continued　emission　of　carburetted　hydrogen　certainly　showed　the　existence　of　a　new　coal…seam。　If　it　had　been　merely　a　sort　of　pocket；　full　of　gas；　as　it　is　sometimes　found　amongst　the　rock；　it　would　soon　have　been　empty；　and　the　phenomenon　have　ceased。　　But　far　from　that。　According　to　Simon　Ford；　the　fire…damp　escaped　incessantly；　and　from　that　fact　the　existence　of　an　important　vein　might　be　considered　certain。　Consequently；　the　riches　of　the　Dochart　pit　were　not　entirely　exhausted。　The　chief　question　now　was；　whether　this　was　merely　a　vein　which　would　yield　comparatively　little；　or　a　bed　occupying　a　large　extent。

Harry；　who　preceded　his　father　and　the　engineer；　stopped。


〃Here　we　are！〃　exclaimed　the　old　miner。　　〃At　last；　thank　Heaven！　you　are　here；　Mr。　Starr；　and　we　shall　soon　know。〃　The　old　overman's　voice　trembled　slightly。

〃Be　calm；　my　man！〃　said　the　engineer。　　〃I　am　as　excited　as　you　are；　but　we　must　not　lose　time。〃

The　gallery　at　this　end　of　the　pit　widened　into　a　sort　of　dark　cave。　No　shaft　had　been　pierced　in　this　part；　and　the　gallery；　bored　into　the　bowels　of　the　earth；　had　no　direct　communication　with　the　surface　of　the　earth。

James　Starr；　with　intense　interest；　examined　the　place　in　which　they　were　standing。　　On　the　walls　of　the　cavern　the　marks　of　the　pick　could　still　be　seen；　and　even　holes　in　which　the　rock　had　been　blasted；　near　the　termination　of　the　working。　The　schist　was　excessively　hard；　and　it　had　not　been　necessary　to　bank　up　the　end　of　the　tunnel　where　the　works　had　come　to　an　end。　There　the　vein　had　failed；　between　the　schist　and　the　tertiary　sandstone。　From　this　very　place　had　been　extracted　the　last　piece　of　coal　from　the　Dochart　pit。

〃We　must　attack　the　dyke；〃　said　Ford；　raising　his　pick；　〃for　at　the　other　side　of　the　break；　at　more　or　less　depth；　we　shall　assuredly　find　the　vein；　the　existence　of　which　I　assert。〃

〃And　was　it　on　the　surface　of　these　rocks　that　you　found　out　the　fire…damp？〃　asked　James　Starr。

〃Just　there；　sir；〃　returned　Ford；　〃and　I　was　able　to　light　it　only　by　bringing　my　lamp　near　to　the　cracks　in　the　rock。　Harry　has　done　it　as　well　as　I。〃

〃At　what　height？〃　asked　Starr。

〃Ten　feet　from　the　ground；〃　replied　Harry。

James　Starr　had　seated　himself　on　a　rock。　　After　critically　inhaling　the　air　of　the　cavern；　he　gazed　at　the　two　miners；　almost　as　if　doubting　their　words；　decided　as　they　were。　In　fact；　carburetted　hydrogen　is　not　completely　scentless；　and　the　engineer；　whose　sense　of　smell　was　very　keen；　was　astonished　that　it　had　not　revealed　the　presence　of　the　explosive　gas。　At　any　rate；　if　the　gas　had　mingled　at　all　with　the　surrounding　air；　it　could　only　be　in　a　very　small　stream。　　There　was　no　danger　of　an　explosion；　and　they　might　without　fear　open　the　safety　lamp　to　try　the　experiment；　just　as　the　old　miner　had　done　before。

What　troubled　James　Starr　was；　not　lest　too　much　gas

mingled　with　the　air；　but　lest　there　should　be　little　or　none。

〃Could　they　have　been　mistaken？〃　he　murmured。　　〃No：　　these　men　know　what　they　are　about。　　And　yet〃

He　waited；　not　without　some　anxiety；　until　Simon　Ford's　phenomenon　should　have　taken　place。　　But　just　then　it　seemed　that　Harry；　like　himself；　had　remarked　the　absence　of　the　characteristic　odor　of　fire…damp；　for　he　exclaimed　in　an　altered　voice；　〃Father；　I　should　say　the　gas　was　no　longer　escaping　through　the　cracks！〃

〃No　longer！〃　cried　the　old　minerand；　pressing　his　lips　tight　together；　he　snuffed　the　air　several　times。

Then；　all　at　once；　with　a　sudden　movement；　〃Hand　me　your　lamp；　Harry；〃　he　said。

Ford　took　the　lamp　with　a　trembling　hand。　　He　drew　off　the　wire　gauze　case　which　surrounded　the　wick；　and　the　flame　burned　in　the　open　air。

As　they　had　expected；　there　was　no　explosion；　but；　what　was　more　serious；　there　was　not　even　the　slight　crackling　which　indicates　the　presence　of　a　small　quantity　of　firedamp。　Simon　took　the　stick　which　Harry　was　holding；　fixed　his　lamp　to　the　end　of　it；　and　raised　it　high　above　his　head；　up　to　where　the　gas；　by　reason　of　its　buoyancy；　would　naturally　accumulate。　The　flame　of　the　lamp；　burning　straight　and　clear；　revealed　no　trace　of　the　carburetted　hydrogen。

〃Close　to　the　wall；〃　said　the　engineer。

〃Yes；〃　responded　Ford；　carrying　the　lamp　to　that　part　of　the　wall　at　which　he　and