116 W. M. DAVIS RELATION OF GEOGRAPHY TO GEOLOGY 



younger part possess the essential features of the Front Eange in central 

 Colorado, of central Wisconsin, of eastern Devonshire, of eastern Brit- 

 tany, of the western and northern border, of the central highland of 

 France, of the northeastern extension of this highland, known as the 

 Morvan, of the western side of the Yosges, of the eastern side of the 

 Odenwald and the Schwarzwald. In northern Arizona .there is an ideally 

 perfect example of such a structure, which instead of being uplifted in 

 modern geological times into a new cycle of erosion, was in ancient geo- 

 logical times depressed and buried under about two miles of strata, the 

 triple mass being afterward uplifted and so deeply eroded that the buried 

 double mass is shown in a superb natural section at the bottom of the 

 Grand Canyon of the Colorado. It would be helpful to have a name that 

 should be used in talking about the recurrent geographical features of all 

 such structurally similar masses, the name being applied more particu- 

 larly to the area of the older resistant rocks which ordinarily stand in 

 relief as an upland or highland in the current cycle, but at the same time 

 being used to indicate the relation in which the upland or highland stands 

 to the adjacent lower area of inclined stratified rocks. Structurally con- 

 sidered, the problem here involved has been called by one of my students 

 the problem of intersecting peneplains ; but that is a phrase, not a name ; 

 so the search for a name had to be continued during our summer pil- 

 grimage and for some time without success, until one day, patience being 

 exhausted, I exclaimed : "Let us call the thing a skiou !" "What is a 

 skiou?" asked my companions. "A skiou is the thing we have been talk- 

 ing about." "What is the origin of the word?" "It hasn't any origin; 

 it is made up from nothing, like the words "gas" and "boss ;" let us use it 

 till we find something better." "How is it spelled ?" "It never has been 

 spelled, but it is going to be spelled s-k-i-o-u ; its plural shall be in s, and 

 its gender is masculine." This last declaration, be it noted, was made to 

 satisfy my French and German companions. Thereupon skiou was used 

 by all of us in a provisional way, and one of the party illustrated a num- 

 ber of different kinds of skious by a series of block diagrams, in which the 

 essential elements were given different values. When a new pilgrim- 

 joined us, we talked familiarly of skious in his presence, just as petrogra- 

 phers talk of eleolite-syenites, or hypersthene-andesites, wherever they 

 are; thereupon the newcomer would lean toward his neighbor and ask 

 in an undertone, "What is a skiou?" and his neighbor would say aloud, 

 "Don't you know what a skiou is ! Say, fellows, here is a man who never 

 heard of a skiou." Thus we developed a sort of initiation ceremony, and 

 when the next newcomer arrived it was for his predecessor to exclaim^ 

 "What ! have you never heard of a skiou ?" 



