JIOKN KXPKDITIOX — NAUHATIVK. 107 



Tlichit; two ritlgcs uiul the IIt)rii V.-illcy between them funu (jiie ut' tlie iii(j«t 

 striking pliysiognipliie features of this part t>i the country. At four special places* 

 the I'idges were broken through by river gorges, and the fact that in eacli case tlie 

 north and south ridges are both cut througli in this way at points o}>posit(! to one 

 another goes far towards demonstrating the truth of the theory that the gorges 

 have been gradually cut Ijy the watercourses while the ridges were in cour'se of 

 being elevated. 



The only otlier way in which these gorges c(ndd have been foinied was by the 

 union of r'avines wliich by chance lay e.\actly oj)posite to one another' on the two 

 sides of the r'anges. 



If the gor-ges wer'e ibrmeil in this way it is a very remarkable coiircidence that 

 in the ca.se of both the m.uir strearrr of the Finke arrd its large triljutaries, the 

 Ellery and the Hugh, such gor'ges should have beerr formed iwocl/y opposite to orre 

 arrother' in the Irigh quartzite r'idges which rrow form the two rarrges, enclosing 

 between t.lieni tire lloi'n Valley. 



Irr no instance ar'e any other' gorges forrired opposite to each other in this 

 way, and thi'rr in addition to this the lorrg wirnling gor'ge of the Firrke — rrrore tliarr 

 forty miles in length — thr-ough the Jarrres Ivarrgc, which has beerr holioweil out l>y 

 the sairre str'earrr as the one which rarrrs through the northern gor'ges, carr only Ije 

 satisfactorily explairred by supposing it to have Ijeerr cut by the river as the 

 larrd r-ose.f 



rf we sujiposc! the river' courses to have beerr deter'iiiirred sirrce the date of 

 upheaval of the riilges, their it is arr inexplicable featur'(! that orrly minor' str'eanis 

 should follow tlie tr'(>iid of the longitudinal folils whilst the four main ones — the 

 Firrke proper with its la.r'ge tr'iliutaries the Elleiy and the Hugh and again 

 further eastward the Todd — should run in a- dir'ection practically at r'iglrt angles to 

 the length of the r'idges and that only small tributaries should flow irrto them fr'om 

 the valleys — two or' thr-ee hundred irriles irr length — which tlrc^y cut across in their 

 course southwards to tln' gr'eat Cr'i^taceous plain which gi-.'idu.-illy sinks towai'ds 

 Lake Eyr-e. 



* There are otlier yor^'us formcil, Imt I am lure only refiiriii'^ to thu fmir spots at which ^or^'os arc forninl 

 through the two ridj^es o|i|iositi' In uiic ;iiiiithc'i-. 



tThe .lames K'aii,i;e is liiifurtiin.itely x ery iiiailei|uatel\ reiireseiited in tlie iiia|i. The Krieli:iult and Waterhouse 

 Ranges are directly coiitiiiucms with one aic ther and fiirni only a northern portion of the .James Itanne. The loni; 

 Kinke (ior^e, here referred to, cuts across the latter from llermaiinshnr^' in the north to a little distance to the 

 north of the point at which it is i-cprcsented in the map as joined hy the llpilla t'reek. 



