162 THE CANADIAN NATURALIST. [Vol. X. 



other layers is used for road metal, and only the more shaly 

 limestones are rejected. The " Blue-Buildinij: beds," although 

 somewhat earthy, form fair building material. At the old 

 quarry along Rosseaux Creek, and elsewhere, in the higher portion 

 of the series, good, fairly thick blocks of dolomite can be obtained 



Though the limestones are generally rather dark, they burn to 

 white lime, as the coloring is derived from organic matter. The 

 principal limekilns arc supplied from the highest beds of the 

 Niagara series in the region of Hamilton and Dundas, while at 

 Limehouse. on the Grand Trunk Railway, the lower beds are 

 light colored, rather pure, and form excellent lime — Toronto and 

 many other places being supplied with immense quantities of the 

 product of these kilns. Some of the beds also burn to hydraulic 

 cement. 



However, there arc interesting minerals in this region, other 

 than those which can be turned to use in the arts. The first of 

 these minerals that we will notice is epsomite. This mineral occurs 

 on both sides of Glen Spencer. It is found as an eflBorescence 

 on the edges of the Niagara shales which are protected by over- 

 hanging thick beds of dolomite. This salt has arisen from the 

 disintegration of the adjacent dolomitic beds and the action of 

 decomposing pyrites. In various other protected places this 

 efflorescence is seen, but it does not consist of pure epsomite 

 being mixed with carbonate of lime, carbonate of iron, sand and 

 clay. 



In the five foot bed of dolomite (No. 8) fine cabinet specimens 

 oi' selenite and crystalline harite can be obtiiiued. Also massive 

 gypsum^ handsome crystals of cilcite (variety of dog-tooth spar), 

 celestite and quartz in small crystals, as well as iron pyrites are 

 found. Many of the cavities when broken open are found to be 

 filled with alkaline waters. In one of the Clinton beds, east of 

 the "Jolly Cut" road, I have found fine red and green crystals 

 of bar if e. However, the handsomest specimens were obtained in 

 Carpenter's Quarry, on lot 7, Range VII, of Barton, not now 

 worked. Fine specimens of crystallized dolomite (pearl spar) 

 calcite (in large scalene dodecahedrons, and in other modifica- 

 tions of rhombohedrons), blende^ pyrites, galena^ purple, smoky 

 and y eWow Jiuorite in fine cubes, and several forms of bituminous 

 matter, both liquid and solid (a variety of which was elastic) 

 were found in considerable quantities filling the cavities of 

 the rock, and often lining what were once crystallites. It was 



