Путешествие на Луну
The Telescope of the Rocky Mountains
Inthepresentcase,dealingwithaprojectileninefeetindiameterandfifteenfeetlong,itbecamenecessarytobringthemoonwithinanapparentdistanceoffivemilesatmost;andforthatpurposetoestablishamagnifyingpowerof48,000times.
SuchwasthequestionproposedtotheObservatoryofCambridge,Therewasnolackoffunds;thedifficultywaspurelyoneofconstruction.
Afterconsiderablediscussionastothebestformandprincipleoftheproposedinstrumenttheworkwasfinallycommenced.AccordingtothecalculationsoftheObservatoryofCambridge,thetubeofthenewreflectorwouldrequiretobe280feetinlength,andtheobject-glasssixteenfeetindiameter.Colossalasthesedimensionsmayappear,theywerediminutiveincomparisonwiththe10,000foottelescopeproposedbytheastronomerHookeonlyafewyearsago!
Regardingthechoiceoflocality,thatmatterwaspromptlydetermined.Theobjectwastoselectsomeloftymountain,andtherearenotmanyoftheseintheUnitedStates.Infacttherearebuttwochainsofmoderateelevation,betweenwhichrunsthemagnificentMississippi,the"kingofrivers"astheseRepublicanYankeesdelighttocallit.
EastwardsrisetheAppalachians,theveryhighestpointofwhich,inNewHampshire,doesnotexceedtheverymoderatealtitudeof5,600feet.
