Canada

• geology

58:7.4In North Amer­ica this an­cient and prim­i­tive fos­sil-bear­ing stone layer comes to the sur­face over the east­ern, cen­tral, and north­ern re­gions of Canada. There is also an in­ter­mit­tent east-west ridge of this rock which ex­tends from Penn­syl­va­nia and the an­cient Adiron­dack Moun­tains on west through Michi­gan, Wis­con­sin, and Min­nesota. Other ridges run from New­found­land to Al­abama and from Alaska to Mex­ico.

• geology

59:3.9280,000,000 years ago the con­ti­nents had largely emerged from the sec­ond Sil­urian in­un­da­tion. The rock de­posits of this sub­mer­gence are known in North Amer­ica as Ni­a­gara lime­stone be­cause this is the stra­tum of rock over which Ni­a­gara Falls now flows. This layer of rock ex­tends from the east­ern moun­tains to the Mis­sis­sippi val­ley re­gion but not far­ther west ex­cept to the south. Sev­eral lay­ers ex­tend over Canada, por­tions of South Amer­ica, Aus­tralia, and most of Eu­rope, the av­er­age thick­ness of this Ni­a­gara se­ries be­ing about six hun­dred feet. Im­me­di­ately over­ly­ing the Ni­a­gara de­posit, in many re­gions may be found a col­lec­tion of con­glom­er­ate, shale, and rock salt. This is the ac­cu­mu­la­tion of sec­ondary sub­si­dences. This salt set­tled in great la­goons which were al­ter­nately opened up to the sea and then cut off so that evap­o­ra­tion oc­curred with de­po­si­tion of salt along with other mat­ter held in so­lu­tion. In some re­gions these rock salt beds are sev­enty feet thick.

• geology

59:4.6260,000,000 years ago, to­ward the end of this land-de­pres­sion epoch, North Amer­ica was par­tially over­spread by seas hav­ing si­mul­ta­ne­ous con­nec­tion with the Pa­cific, At­lantic, Arc­tic, and Gulf wa­ters. The de­posits of these later stages of the first De­vo­nian flood av­er­age about one thou­sand feet in thick­ness. The coral reefs char­ac­ter­iz­ing these times in­di­cate that the in­land seas were clear and shal­low. Such coral de­posits are ex­posed in the banks of the Ohio River near Louisville, Ken­tucky, and are about one hun­dred feet thick, em­brac­ing more than two hun­dred va­ri­eties. These coral for­ma­tions ex­tend through Canada and north­ern Eu­rope to the arc­tic re­gions.

• geology

59:5.17In North Amer­ica the lay­ers of coal in the var­i­ous beds, which in­di­cate the num­ber of times the land fell and rose, vary from ten in Illi­nois, twenty in Penn­syl­va­nia, thirty-five in Al­abama, to sev­enty-five in Canada. Both fresh- and salt-wa­ter fos­sils are found in the coal beds.

• geology

61:7.9150,000 years ago the sixth and last glacier reached its far­thest points of south­ern ex­ten­sion, the west­ern ice sheet cross­ing just over the Cana­dian bor­der; the cen­tral com­ing down into Kansas, Mis­souri, and Illi­nois; the east­ern sheet ad­vanc­ing south and cov­er­ing the greater por­tion of Penn­syl­va­nia and Ohio.