CocKBURN-HooD. — Xew Zealand a Pust-r/lacial Centre of Creation. 11 



There lias been no ice work going on there since the Colorado began to 

 cut its mighty drain a mile and a quarter deep, where it is at the same 

 time but one hundred and eighty feet across ; the three hundred feet of the 

 lowest portion of this extraordinary chasm being eroded through hard 

 granite. Wlien this great work commenced, according to reasonable 

 calculations, the northern currents must have been spreading drift on the 

 submerged eastern plains, if that operation went on during the glacial 

 period of Su- Charles Lyell. 



The moraines of ancient local glaciers may be seen on the sloj)es of 

 these mountains below 39° N. latitude, and also upon those of the Sierra 

 Nevada, still nearer to the tropics, but traces of general glaciation there or 

 of northern drift on the shores of California of the same age as that on the 

 eastern side of the Missouri have not hitherto been observed. The vast 

 accumulations of shingle on the terraces of Oregon and Washington terri- 

 tory are as ancient, according to American geologists, as those of the 

 highest plateau of the prairies east of the Eocky Mountains, and are 

 composed, as the latter are likewise, of materials of local derivation. They 

 were deposited there when the Cascade Eange abeady presented a formid- 

 able wall, and previous to the time when Mount Hood, Mount Eainier, 

 and Shasta, those grand "Lookers-on"' of the Pacific Coast, were piled up. 

 The boulders which lie on these old shingle terraces on the sides of the 

 Willamette and other valleys, and on the shores of Vancouver, may be 

 pointed to as memorials of the " Great Age of Ice," but they cannot be 

 proved to have travelled very far. The grey syenite of which the majority 

 of them consist, is a distinguishing rock of the Cascade Eange, from 

 whence glaciers brought them down probably during a local period of cold. 

 On the Atlantic side of the Mississippi basin, erratics were 

 dropped in certain meridians, as far south as the 37th degree of lati- 

 tude, when the way was open over the great lake region then submerged 

 to the polar sea, just as they are being now on the American side of the 

 Atlantic, nearer to the tropic than they were at that era. 



Ice-polished and striated boulders, floated from afar in distant ages, 

 may lie buried under the soil of the Californian plains, but none have been 

 discovered by American observers. I could see no foreign stones or ancient 

 ice-marks on the slopes of Calaveras or Mariposa, above Yosemite. 



There is a vast river in the Pacific coming from equatorial regions, 

 entitled to be described in the same expressive language with which Maury 

 introduces his readers to the consideration of the Gulf Stream. It sweeps 

 near the coast of Japan past Yokohama, leaving the shores of Yesso further 

 off than it does those of Nipon, and has flowed in the same course, temper- 

 ing its chmate and causing hurricanes in its seas, we may conclude from 



