1854.] 



" GEOLOGY 0¥ WESTERN CANADA. 



(0 



derives its appellation;; to yield building materials, the rock 

 then becomes applicable as road metal, for which it is •vvcll 

 adapted ; the hornstone prevails chiefly in the lower part of 

 the formation. 



Hamilton Group. 



In a low cliff on the west side of Cape Ipperwash or Kettle 

 Point, there is displayed a vertical amount of about twelve to 

 fourteen feet of black bituminous shale, which splits into very 

 thin laminas, and weathers to a dull lead colour, marked iu 

 many places by extensive brown stains from oxyd of iron, 

 while patches of the exterior in such parts as are not washed 

 by the water of the lake, are encrusted with a yellowish 

 sulphurous looking powder. ='= Many nodules and crystals of 

 iron pyrites are enclcsod in the shales, and many peculiar 

 spherical concretions. On the east side of the Point the 

 upper beds of the section are concealed by debris, but the 

 lower come out from beneath the bank, exposing their surfaces 

 a little above the level of the water, studded by the spherical 

 concretions, over an area of several square acres. The resem- 

 blance these concretions bear in many instances to inverted 

 kettles has probably been the origin of the name commonly 

 applied to the Point ; they are of all sizes from three inches to 

 three feet in diameter, and while many of them are nearly 

 perfect spheres, others are flattened a little, generally on the 

 under .side ; sometimes they present one sub-spherical mass on 

 the top of another, the upper of which is smaller than the 

 under, giving a rude resemblance to a huge acorn ; the masses 

 split open w'ith facility, both vertically and horizontally, and 

 when double forms occur they are readily divided horizontally. 

 These concretions are all composed of a dark gray crystalline 

 limestone, presenting in many cases a confiised aggregation of 

 crystals in the centre, from the nucleus formed by which slender 

 elongated prisms radiate very regularly throughout the mass to 

 the circumference. In the nucleus are sometimes met with 

 small disseminated specks of blende, but these were not ob- 

 served to extend to the radiating prisms, which both in their 

 terminations on the exterior of the sphere, and in their filiform 

 aspect in the radii on fractured surfaces, give the mass very 

 much the semblance of a fossil coral, for which it might 

 readily be mistaken. 



The shale is fossiliferous, and among the remains a fucoid 

 resembling the Fncvidcs cauda galli of Vanuxem is very 

 abundant, chiefly in the lower beds. Stems of plants sup- 

 posed to be species of Catamites, in some instances seven to 

 eight feet long with a breadth of three inches, are frequently 

 seen about the )niddle of the section, and in these are some- 

 times remarked patches of a thin coating of coal, which no 

 doubt when freshly exposed, invested the whole plant. In 

 one place a Linrjula (but neither of the two species represented 

 by jMr. Hall as belonging to the Genesee slate,) was found 

 associated witii plants, in addition to what appears to be a 

 number of minute orbicular microscopic shells. 



The whole of the beach where these bituminous shales 

 occur, appears to have been overrun by fire, which is rumoured 

 by the Indians and others acquainted with that section of 

 country, to have originated sp(jntancously, and to have con- 

 tinued burning I'or several consecutive years. That rocks con- 

 taining so uMch bituminous matter, once ignited, should not 



* The sub.stanco is soft, ilull, cartliy, of a sulplmr yellow, and in 

 aiMition to possessing the exterior aspect, gives the blow pipe reactions 

 of Ilumboldline or oxulite of iron. It instantly lilackens in the tlame, 

 without any sulivhurous odour, and hccoincs magnetii;, leaving, by the 

 continuance of the heat, a briirbt red .stain. 



cease to burn for months or even years, is very probable ; but 

 it is difficult to ascertain satisfactorily whether the fire was the 

 result of natural causes or of accident. Spontaneous combus- 

 tion is known to be of frequent occurrence near colleries, 

 where bituminous shale is thrown up in heaps as refuse result- 

 ing from the working of the coal, when the shale is_ of a 

 crumbling nature, audi is accompanied by iron pyrites, a mineral 

 present in most coal seams. It is not in my power to explain 

 the phenomenon dearly, but it is supposed to be connected 

 with the decomposition of the pyrites ; but in the case of 

 Kettle Point the same materials, bituminous shale and pyrites 

 are present together, and it is not unreasonable to suppose that 

 their action on one another may have originated the ignition. 

 We obsei-ved that on digging a foot deep or more into the 

 shingle, a faint and almost colourless vapour immediately arose 

 from" the opening, which, gradually increasing in volume and 

 density, in the space of two or three minutes, became a distinct 

 smoke, omitting an odour very similar to that produced by the 

 combustion of a sulphurous coal, and evolving at the sarue 

 time a con.siderable heat. The shingle of the beach, which is 

 almost exclusively derived from the formation, is of a bright 

 red colour wherever the fire has extended, the bituminous 

 matter having entirely disappeared. 



The black colour and inflammable nature of the bituminous 

 shales of Kettle Point have suggested to some persons, as in 

 the case of the bituminous shales of the Utica slate in other 

 parts of the Province, the possibility of their proximity to 

 available coal seams. But the formation to which they belong 

 is well known in the State of New York, where useless and 

 expensive experiments were made in it, before the institution 

 of the State Geological Survey, in a vain search for mineral 

 fuel ; the formation has the name of the Hamilton Group, at 

 the base and at the summit of which there are black bitumi- 

 nous shales, in the former case called the Marcellus, and in the 

 latter the Genessee slate, either of them corresponding with 

 the general condition of the Kettle Point shales ; but between 

 the Hamilton Group and the coal areas south-east of Lake 

 Erie, on the one hand, and north-west of Lake St. Clair on 

 the other, there occurs an important group of sandstones 

 (called the Chemung and Portage Group) ; no trace of these 

 sandstones any more than of the Carboniferous Group, has yet 

 been met with in Western Canada. 



Drift. 



A great accumulation of drift was observed on the margin 

 of tlie lake and on the banks of the rivers south of the Puviere 

 au TBable (north,) consisting of clay, gravel, sand, and boulders. 

 Allusion has already been made to their distribution on the 

 coast, and from this they extend into the interior, and cover 

 the greater part of the country between Lakes I'^ric and Huron. 

 The clay in the clifis overlooking the latter, was found to be 

 very calcareous, containing sometimes so much as oO per cent, 

 of carbonate of lime, and constituting a rich marl, which would 

 be of advantageous application, in an agricultural point of view, 

 to the sandy portions of the district. The clay often contains 

 numerous pebbles and boulders of limestone, quartz, granite 

 and allied species derived from the niins of rocks similar to 

 those found in place in one part or other of the shore around 

 the lake. Those of limestone were often cliscovered to Indd 

 fossils peculiar to the Cornifcrous furniation. especially in the 

 Township of Plympton, where they were numerous but usually 

 water worn. The sands met with on the coast consisted of 

 fine grains of white C|uartz ; equally fine grains of uiica, feld- 

 spar and limestone were distriLuted in smaller proportions, 



