4 DE. EOBEET BELL : 



of Eastern Ontario, such as those in the counties of Hastings, Lanark, etc., may be best 

 correlated with this system. 



The Huroniau may be considered as preeminently the metalliferous system of Canada, 

 and of the Northern States east of the Rocky Moiintains. 



The green and grey schists and " slate conglomerates " prevail towards the bottom, and 

 the quartzites, greywackes and clay-slates are mostly developed towards the top. The 

 Huronian System, as a whole, is conformable to the Laurentian, although some of the 

 upper beds may be locally unconformable to some of the lower ones belonging to the 

 same system, or to the Laurentian, but singularly enough, no instance of the latter kind 

 has yet been observed in Canada. It has a great thickness — probably much greater than 

 has hitherto been attributed to it — amounting, perhaps, to forty or fifty thousand feet. 

 The deposition of so vast a thickness of strata would, of course, imply the lapse of an 

 immense period of time, during which great changes took place. The older members 

 would have time to become consolidated, disturbed and eroded before the formation of 

 the newer, which would necessarily be, to some extent, made up of the debris of the 

 former. Hence, local discordances may naturally be looked for. Rocks of such ancient 

 date, whether stratified or otherwise, must have undergone structural and other changes 

 too profound for us to trace, and hence their original state, compared with their present 

 condition, can often be only conjectured. In cases where a want of conformity originally 

 existed, the strata may have been squeezed into an apjjarently conformable arrangement ; 

 and again, an apparent want of conformity, if such should be found, may have been the 

 result of foldings and dislocations. We should not, therefore, lay too much stress on 

 questions of this nature. My present purpose is to inquire whether the rocks referred to 

 are important enough and sufficiently well defined, as to internal characters and as to 

 position in the geological scale, to retain their place as a system, equivalent to Cambrian, 

 Silurian, etc.. and whether it is desirable in the interests of geological science to divide 

 them, and if so, whether such divisions can be well established and defined. 



In the " Geology of Canada," 1863, Sir William Logan describes fully what is meant 

 by the term " Huronian." Notwithstanding this. Prof. Irving now defines it to be some- 

 thing else, and attempts, without, I think, sufficient reason, to divide it into two parts, 

 retaining the name for only some of the upper members, and reducing the series to the 

 rank of a mere group. What he proposes to do with the rest of Logan's Huronian is not 

 made clear. For a short definition he calls the Huronian "a detrital, iron-bearing series." 

 If any single feature were to be selected as the most characteristic of the Huronian, I 

 should say it is the igneous origin of so large a proportion of its members, rather than the 

 circumstance that it contains ores of iron. 



The fact that the green schist portions of the series on Lake Superior, for example, ai-e 

 not precisely of the same horizon as the Lake Huron quartzites, was never disputed by 

 us. On the contrary, it has always been admitted that a vast system like the Huronian 

 must have a beginning and an end — a top and a bottom — and in the Greological Survey 

 we have always been in the habit of talking of the Upper and Lower Huronian. I have 

 done so with Dr. Selwyn for fifteen years. At the same time we did not consider that we 

 had yet arrived at a sufficiently precise knowledge of these rocks, to be able to draw up 

 exact descriptions of what their subdivisions should be — and this notwithstanding that 

 we have been at work on them for some forty-five years, and over an area equal to about 



