62 On the Minerals of Canada. 



amount, far greater tlian was ever expected to be acquired in so 

 short a period, over a country so extensive and little known, and 

 witli means so inadequate to the end, yet it is not to be understood 

 that discoveries equal in importance to those already made may 

 not year by year inform us of fresh treasures before unthought of. It 

 is only the other day that a band of rock was discovered, so ad- 

 mirably adapted to the milling purposes for which Burrstones are 

 employed, that we may not only become independent of foreigners 

 for that important article, but enabled to export them to other 

 countries. 



The discovery of hydraulic lime in some of the strata on which 

 the city of Quebec stands tells, by means of a geological knowledge 

 of the country, of the existence of hydraulic lime for hundreds of 

 miles. The ascertained southern limits of the Huronian copper 

 bearing rocks on lake Huron and Superior indicate a copper 

 yielding country in which a search for that metal may be prosecu- 

 ted over many thousand square miles with every prospect of suc- 

 cess. 



The influence indeed of a single discovery of an economic ma- 

 terial in any strata acquires importance which cannot easily be 

 estimated, when the known extent of the rock which holds it oc- 

 cupies wide areas. It is for this purpose that a general study of 

 geological outlines of the country is so useful, and in our time 

 even necessary. Think of the advantage to the settlers in the 

 Ottawa region to know of the existence of Crystalline Limestones 

 beneath their feet, over which they have been many years jour- 

 neying 15 and 20 miles for the same indispensable material to the 

 great River Ottawa itself, where it is exposed in a form to which 

 they have been accustomed. But expand the ideas conveyed in 

 this simple announcement to the whole region in Canada where it 

 may apply, and we find that a knowledge of the structure of the 

 Laurentian Eocks, which extend from Labrador to Lake Huron, 

 and thence on towards the Mackenzie River, tells us of the exis- 

 tence of Crystalline Limestone throughout the whole of the vast 

 country and limestone is an indispensable necessity of civilized life. 

 But we may amplify still farther and point to the iron ores gene- 

 rally associated with these limestones. I have spoken in a former 

 lecture of the vast magnetic beds, of Marmora, Madoc, Belmont 

 and Hull ; these are generally found in juxta-position with beds of 

 crystalline limestone. When this great fact becomes generally 

 known among fature settlers in the Laurentine Country, and they 



