an autobiography-第79部分

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？　floating　in　a　fluid　of　their　own；　or　very　nearly　their　own；　specific　gravity？　　Some　kind　of　solidity　or　coherence　they　must　have；　or　they　would　not　retain　their　shape　in　the　violent　movements　of　the　atmosphere　which　the　change　of　the　spots　indicate。

〃I　observe　that　in　the　bridges　all　their　axes　have　an　approximate　parallelism；　and　that　in　the　penumbra　they　are　dispersed；　radiating　from　the　inside　and　the　outside　of　the　spot；　giving　rise　to　that　striated　appearance　which　is　familiar　to　all　observers　of　the　spots。

〃I　am　very　glad　that　you　have　pitched　your　tent　in　this　part　of　the　world；　and　I　only　wish　it　were　a　little　nearer。　　You　will　anyhow　have　the　advantage　at　Penshurst　of　a　much　clearer　atmosphere　than　in　the　north；　but　here；　nearer　the　coast；　I　think　we　are　still　better　off。　〃Mr。　Maclaren　holds　out　the　prospect　of　our　meeting　you　at　Pachley　at　no　distant　period；　and　I　hope　you　will　find　your　way　ere　long　to　Collingwood。　　I　have　no　instruments　or　astronomical　apparatus　to　show　you；　but　a　remarkably　pretty　country；　which　is　beginning　to　put　on　（rather　late）　its　gala　dress　of　spring？'

Sir　John　afterwards　requested　my　permission　to　insert　in　his　Outlines　of　Astronomy；　of　which　a　new　edition　was　about　to　appear；　a　representation　of　〃the　willow…leaved　structure　of　the　Sun's　surface；〃　which　had　been　published　in　the　Manchester　transactions；to　which　I　gladly　gave　my　assent。　　Sir　John　thus　expresses　himself　on　the　subject：　〃The　curious　appearance　of　the　'pores'　of　the　Sun's　surface　has　lately　received　a　most　singular　and　unexpected　interpretation　from　the　remarkable　discovery　of　Mr。　J。　Nasmyth；　who；　from　a　series　of　observations　made　with　a　reflecting　telescope　of　his　own　construction　under　very　high　magnifying　powers；　and　under　exceptional　circumstances　of　tranquillity　and　definition；　has　come　to　the　conclusion　that　these　pores　are　the　polygonal　interstices　between　certain　luminous　objects　of　an　exceedingly　definite　shape　and　general　uniformity　of　size；　whose　form　（at　least　as　seen　in　projection　in　the　central　portions　of　the　disc）　is　that　of　the　oblong　leaves　of　a　willow　tree。　　These　cover　the　whole　disc　of　the　Sun　（except　in　the　space　occupied　by　spots）　in　countless　millions；　and　lie　crossing　each　other　in　every　imaginable　direction。。。。　　This　most　astonishing　revelation　has　been　confirmed　to　a　certain　considerable　extent；　and　with　some　modifications　as　to　the　form　of　the　objects；　their　exact　uniformity　of　size　and　resemblance　of　figure；　by　Messrs。　　De　la　Rue；　Pritchard　and　Stone　in　England；　and　M。　Secchi　in　Rome。〃

On　the　25th　of　February　1864；　I　received　a　communication　from　Mr。　E。　J。　Stone；　first　assistant　at　the　Royal　Observatory；　Greenwich。

The　Astronomer…Royal；　he　said；　〃has　placed　in　my　hands　your　letter　of　February　20。　　Your　discovery　of　the　'willow　leaves'　on　the　Solar　photosphere　having　been　brought　forward　at　one　of　the　late　meetings　of　the　Royal　Astronomical　Society；　my　attention　was　attracted　to　the　subject。　　At　my　request；　the　Astronomer…Royal　ordered　of　Mr。　J。　Simms　a　reflecting　eye…piece　for　our　great　equatorial。　　The　eye…piece　was　completed　about　the　end　of　January　last；　and　at　the　first　good　opportunity　I　turned　the　telescope　on　the　Sun。

〃I　may　state　that　my　impression　was；　and　it　appears　to　have　been　the　impression　of　several　of　the　assistants　here；　that　the　willow　leaves　stand　out　dark　against　the　luminous　photosphere。　　On　looking　at　the　Sun；　I　was　at　once　struck　with　the　apparent　resolvability　of　its　mottled　appearance。　　The　whole　disc　of　the　Sun；　so　far　as　I　examined　it；　appeared　to　be　covered　over　with　relatively　bright　rice…like　particles；　and　the　mottled　appearance　seemed　to　be　produced　by　the　interlacing　of　these　particles。

〃I　could　not　observe　any　particular　arrangement　of　the　particles；　but　they　appeared　to　be　more　numerous　in　some　parts　than　in　others。　I　have　used　the　word　'rice…like'　merely　to　convey　a　rough　impression　of　their　form。　　I　have　seen　them　on　two　occasions　since；　but　not　so　well　as　on　the　first　day；　when　the　definition　was　exceedingly　good。

〃on　the　first　day　that　I　saw　them　I　called　Mr　Dunkin's　attention　to　them。　　He　appears　to　have　seen　them。　　He　says；　however；　that　he　should　not　have　noticed　them　if　his　attention　had　not　been　called　to　them。〃

The　Astronomer　Royal；　in　his　report　to　the　Admiralty　on　my　discovery；　said：

〃an　examination　of　the　Sun's　surface　with　the　South…East　Equatorial；　under　favourable　circumstances；　has　convinced　me　of　the　accuracy　of　the　description；　which　compares　it　with　interlacing　willow　leaves　or　rice　grains。〃

In　March　1864　I　received　a　letter　from　my　friend　De　la　Rue；　dated　from　his　observatory　at　Cranford；　Middlesex；　in　which　he　said：　　〃I　like　good　honest　doubting。　　Before　I　had　seen　with　my　own　eyes　your　willow　leaves；　I　doubted　their　real　existence；　but　I　did　not　doubt　your　having　seen　what　you　had　drawn。　　But　when　I　actually　saw　them　for　the　first　time；　I　could　not　restrain　the　exclamation；　'　Why；　here　are　Nasmyth's　willow　leaves！　'　It　requires　a　very　fine　state　of　the　atmosphere　to　permit　of　their　being　seen；　as　I　have　seen　them　on　three　or　four　occasions；　when　their　substantial　reality　can　no　longer　be　doubted。〃*　　＇footnote。。。　Let　me　give　another　letter　from　my　friend；　dated　the　Observatory；　Cranford；　Middlesex；　October　26；　1864。　　He　said：…　〃I　am　quite　pleased　to　learn　that　you　like　the　large　photograph。　The　first　given　to　my　friend　was　destined　for　and　sent　to　you。　No　one　has　so　great　a　claim　on　the　fruit　of　my　labours；　for　you　inoculated　me　with　the　love　of　star…gazing；　and　gave　me　invaluable　aid　and　advice　in　figuring　specula。　　I　daresay　you　may　remember　the　first　occasion　on　which　I　saw　a　reflecting　telescope；　which　was　then　being　tried　on　the　sun　in　a　pattern　loft　at　Patricroft。　　You　may　also　recall　the　volumes　you　wrote　in　answer　to　my　troublesome　questions。　Yours　very　sincerely　WARREN　DE　LA　RUE。〃　　。。。＇

Sir　John　Herschel　confirmed　this　information　in　a　letter　which　I　received　from　him　in　the　following　May。　　He　said　〃that　Mr。　De　la　Rue　and　a　foreign　gentleman；　Hugo　Muller；　had　been　very　successful　in　seeing　and　delineating　the　'willow　leaves'　They　are　represented　by　Mr。　M。　as　packed　together　on　the　edge　of　a　spot；　and　appear　rather　like　a　bunch　of　bristles　or　thorns。　　In　other　respects　the　individual　forms　agree　very　well　with　your　delineations。〃　　Another　observer　had　discovered　a　marvellous　resemblance　between　the　solar　spots　and　the　hollows　left　by　the　breaking　and　subsidence　of　bubbles；　which　rise　when　oil　varnish；　which　has　moisture　in　it；　is　boiled；　and　the　streaky　channels　are　left　by　the　retiring　liquid。　　〃I　cannot　help；〃　adds　Sir　John；　〃fancying　a　bare　possibility　of　some　upward　outbreak；　followed　by　a　retreat　of　some　gaseous　matter；　or　some　dilated　portion　of　the　general　atmosphere　struggling　upwards；　and　at　the　same　time　expanding　outwards。　　I　can　conceive　of　an　up…surge　of　some　highly　compressed　matter；　which　relieved　of　pressure；　will　dilate　laterally　and　upwards　to　an　enormous　extent　（as　Poullett　Scrope　supposes　of　his　lavas　full　of　compressed　gases　and　steam）；　producing　the　spots；　and；　in　that　case；　the　furrows　might　equally　well　arise　in　the　origination　as　in　the　closing　in　of　a　spot。〃

I　had　the　honour　and　happiness　of　receiving　a　visit　from　Sir　John　Herschel　at　my　house　at　Hammerfield　in　the　summer　of　1864。　He　was　accompanied　by　his　daughter。　　They　spent　several　days　with　us。　The　weather　was　most　enjoyable。　　I　had　much　conversation　with　Sir　John　as　to　the　Sun　spots　and　willow…leaf…shaped　objects　on　the　Sun's　surface；　as　well　as　about　my　drawings　of　the　Moon。　　I　exhibited　to　him　my　apparatus　for　obtaining　sound　castings　of　specula　for　reflecting　telescopes。　　I　compounded　the　alloy；　melted　it；　and　cast　a　10…inch　speculum　on　my　peculiar　common…sense　system。　　I　introduced　the　molten　alloy；　chilled　it　in　a　metal　mould；　by　which　every　chance　of　flaws　and　imperfections　is　obviated。　　I　also　showed　him　the　action　and　results　of　my　machine；　by　which　I　obtained　the　most　exquisite　polish　and　figure　for　the　speculum。　　Sir　John　was　in　the　highest　degree　cognisant　of　the　importance　of　these　details；　as　contributing　to　the　final　excellent　result。　　It　was　therefore　with　great　pleasure　that　I　could　exhibit　these　practical　details　before　so　competent　a　judge。

We　had　a　great　set…to　one　day　in　blowing　iridescent　soap　bubbles　from　a　mixture　of　soap　and　glycerine。　　Some　of　the　bubbles　were　of　about　fifteen　inches　diameter。　　By　carefully　covering　them　with　a　bell　glass；　we　kept　them　for　about　thirty…six　hours；　while　they　went　through　their　changes　of　brilliant　colour；　ending　in　deep　blue。　　I　contrived　this　method　of　preserving　them　by　placing　a　dish　of　water　below；　within　the　covering　bell　glass；　by　means　of　which　the　dampness　of　the　air　prevented　evaporation　of　the　bubble。　　This　dodge　of　mine　vastly　delighted　Sir　John；　as　it　allowed　him　to　watch　the　exquisite　series　of　iridescent　tints　at　his　tranquil　leisure。

＇Image＇　　From　a　photograph　of　the　Moon；　exhibiting　the　bright　radial　　　　　　　　　　lines。

＇Image＇　　Glass　globe　cracked　by　internal　pressure；　in　illustration　of　　　　　　　　　　the　cause　of　the　bright　radial　lines　seen　on　the　moon。

I　had　also　the　pleasure　of　showing　him　my　experiment　of　cracking　a　glass　globe　filled　with　wat