306 R. BELL — GLACIAL PHENOMENA IN CANADA. 



seem:- to indicate thai these bowlders have been carried either in the midst 

 of the ice or on the back of the glacier, which they must have reached by 

 passing upward through its substance by Borne process which has not yel 

 been clearly demonstrated. 



I noticed thai where the supposed great terminal moraine of the western 

 slope of Hudson's bay is crossed by the Churchill, Little Churchill, Nelson, 

 and Hill rivers, ;i large proportion of the bowlders were angular. This ap- 

 peared to be more especially the case on Hill river, where the stream flows 

 for miles on a bed of angular Laurentian bowlders in the section which 

 traverses the supposed moraine. 



Thi Period of Glaciation. — [n attempting to estimate the time which has 

 elapsed since the glacial period, everyone is struck by the freshness of the 

 striae on many glaciated surfaces, and might argue from such evidence that 

 this period was nol so remote as most geologists have hitherto supposed. It 

 will be found, however, thai most of the well-preserved surfaces have been 

 protected from the weather during the greater part of the time that has 

 elapsed, either by water, which has since disappeared but of which we see 

 bo much evidence, or by earth which has recently been removed. Even the 

 water- of the presenl lake- and river.- have a great effect in preserving the 

 striae. In the Laurentian lake.- they are wonderfully sharp and distinct 

 under the low-water mark, whereas the continuations of the same grooves on 

 exposed surfaces are almost obliterated, although the hard and smoother 



surfaces of the glaciated rocks are well calculated to withstand the influem 



of time. < )n unaltered rocks which have been long exposed the ice-grooves 

 are entirely gone, and the surfaces which we know by their outline mu.-t 

 have been glaciated are crumbled or eroded. 



In thee ty of A.rgenteuil, Sir William Logan described veins of quartz 



cutting crystalline limestone where the striated surfaces of the former stand 

 out from -i\ to nine inches above the general surface of the latter, showing 

 that the limestone ha- been dissolved away to that depth since the striation 

 took place; hut thi- may have all been done during onlyapart of this 

 interval. I have seen many other cases both in Argenteuil and Ottawa 

 counties where hard veins ami lump- embedded iii crystalline limestone and 

 bearing the striae are weathered out to various heights not exceeding one 

 fool above the roughened but Bound Burf'ace of the limestone. 



After all, the surface of any -ton,- hard enough to be used in the building 



of important -tincture- withstands the influence of the weather for long 



periods, as proved by many example- in Italy, Greece, and Palestine, and 

 more particularly in JSgypI and Central America. A smooth and Bound 

 rock-surface produced l>\ glacial rubbing and polishing is better adapted to 

 endure the ravages of time than any artificially hammered surface. The 

 destructive influences of time appear to operate even more -lowly in cold 



