T RAV

ROU1';E FROM MOG-OD.,R TO MûROCCO. 221eye, ordppal'el1t elevation, ls so mucll' additional, and accounts too forthat impending appeàrance of thi8 mountain so'strikingly observable.Calculations may he thought perhaps too nice for their objects,or forthe means'we bave of working them.This, however, inust not be admittadw:hereprirlciples, are conce1'ned.Inpractice, no doubt, thongllour objects are' correctness' and,truth, we must inmallY instances, as11e1'e, l'est satisfied with approximations. ·As to the cause of mirage,and the effects of the medium in judging ofthis vast elevation, it is tobecarriedin,mind; that theatmospherical density decreases (in consistentPatios) bothin the advanceto the southern latitudes and in its ownele'\tatidnfTAis, then, isin favour of the elevation.The higher theobject,îne leSsit 18 affectedhJ' this refraction,; and, the distanoe fromthe perpendicular base, at whieh its' summit-point is taken ,in bytheoye, is also proper matter for computation.Pei'haps, if olle-sixteenthhe allowed fol' the enhancement by visual deception, it may afford atü1erable approach at loast to the reality.But it i8 time to quit this()bject, one not, readily lost 8ight ()f, for the present, and proqeed withthe journey.Fifth da.'t/s' journey.-Quitting our'halting-ground, where the Bassayet'remained, having passed the day closely c()llfined, muffied up, paleand languid in,his tent, the ronte was pursucd throughan open countryfor three hbur~, at the expiration ofwhich haIt were caUed in meadowgroundshytheside ofastream, low atpresent, but at timesa torrent.AU thesewateFsdèscend from, Mount Atlas, al1d are deeply, tinged bythe melaHiferou8 (:rnaywesay?) soilof ils skirts.hypothetically.'l'he subject is putWc areirideed under no;obligation to modern lore foraught of consequence as' tô the· natural history of thi8 country.the ancients te11'us,-" In nullas vitiatur opes; non