Thesunisexcessivelyhot，andfeelssharpinAfrica；but，probablyfromthegreaterdrynessoftheatmosphere，weneverheardofasinglecaseofsunstroke，socommoninIndia。TheMakololotoldDr。Livingstonethey\"alwaysthoughthehadaheart，butnowtheybelievedhehadnone，\"andtriedtopersuadeDr。Kirktoreturn，onthegroundthatitmustbeevidentthat，inattemptingtogowherenolivingfootcouldtread，hisleaderhadgivenunmistakeablesignsofhavinggonemad。Alltheireffortsofpersuasion，however，werelostuponDr。Kirk，ashehadnotyetlearnedtheirlanguage，andhisleader，knowinghiscompaniontobeequallyanxiouswithhimselftosolvetheproblemofthenavigablenessofKebrabasa，wasnotatpainstoenlightenhim。Atonepartabaremountainspurbarredtheway，andhadtobesurmountedbyaperilousandcircuitousroute，alongwhichthecragsweresohotthatitwasscarcelypossibleforthehandtoholdonlongenoughtoensuresafetyinthepassage；
andhadtheforemostofthepartylosthishold，hewouldhavehurledallbehindhimintotheriveratthefootofthepromontory；yetinthiswildhotregion，astheydescendedagaintotheriver，theymetafishermancastinghishand-netintotheboilingeddies，andhepointedoutthecataractofMorumbwa；withinanhourtheyweretryingtomeasureitfromanoverhangingrock，ataheightofaboutonehundredfeet。Whenyoustandfacingthecataract，onthenorthbank，youseethatitissituatedinasuddenbendoftheriver，whichisflowinginashortcurve；theriveraboveitisjammedbetweentwomountainsinachannelwithperpendicularsides，andlessthanfiftyyardswide；oneortwomassesofrockjutout，andthenthereisaslopingfallofperhapstwentyfeetinadistanceofthirtyyards。Itwouldstopallnavigation，exceptduringthehighestfloods；therocksshowedthatthewaterthenrisesupwardsofeightyfeetperpendicularly。
Stillkeepingthepositionfacingthecataract，onitsrightsiderisesMountMorumbwafrom2000to3000feethigh，whichgivesthenametothespot。Ontheleftofthecataractstandsanoticeablemountainwhichmaybecalledonion-shaped，foritispartlyconicalandalargeconcaveflakehaspeeledoff，asgraniteoftendoes，andleftabroad，smoothconvexfaceasifitwereanenormousbulb。
Thesetwomountainsextendtheirbasesnorthwardsabouthalfamile，andtheriverinthatdistance，stillverynarrow，issmooth，withafewdetachedrocksstandingoutfromitsbed。TheyclimbedashighupthebaseofMountMorumbwa，whichtouchesthecataract，astheyrequired。Therockswereallwater-wornandsmooth，withhugepotholes，evenat100feetabovelowwater。Whenatalaterperiodtheyclimbedupthenorth-westernbaseofthissamemountain，thefamiliarfaceoftheonion-shapedoneoppositewasatoncerecognised；onepointofviewonthetalusofMountMorumbwawasnotmorethan700or800yardsdistantfromtheother，andtheythencompletedthesurveyofKebrabasafromendtoend。
Theydidnotattempttoreturnbythewaytheycame，butscaledtheslopeofthemountainonthenorth。Ittookthemthreehours\'hardlabourincuttingtheirwayupthroughthedensethornbushwhichcoveredtheascent。Thefaceoftheslopewasoftenaboutanangleof70degrees，yettheirguideShokumbenla，whosehard，hornysoles，resemblingthoseofelephants，showedthathewasaccustomedtothisroughandhotwork，carriedapotofwaterforthemnearlyallthewayup。TheysleptthatnightatawellinatufaceousrockontheN。W。ofChipereziwa，andneverwassleepmoresweet。