24 Geological Reports on the State of New Yo?'k. 



the granite and projects upward into it in a triangular mass. In 

 Lyndhurst, Upper Canada, the same fact exists, and the Umestone 

 is interspersed among the granite. At Gouverneur there are, near 

 the celebrated locality of phosphate of lime, veins of limestone in- 

 tersecting granite, and branching off from each other ; in other 

 cases the veins of limestone alternate with granite. There is in 

 Harmon, near Tales, one lead ore vein a foot wide. There is 

 also a bed of limestone with angular masses of primary rocks 

 projecting from it, and such instances are common. The lime- 

 stone and granite are in general perfectly distinct, bat sometimes 

 they are blended. 



The frequent occurrence of plumbago in primary limestone is 

 thought to favor its igneous origin, since it is so often produced 

 by furnaces. 



In the vicinity of limestone, quartz is rounded as if from heat, 

 and is converted into hornstone. 



Mr. Hall is of the opinion that the limestone of this region is 

 not stratified, and that its veins branching especially from below, 

 have the same evidence of igneous origin as those of granite and 

 trap. 



Serpentine of great beauty, some of it being verd antique and 

 soapstone, occurs in this county. 



Specular iron is found, and the hearth stones when it is smelted 

 have afforded crystals of metallic titanium. There is also bog ore 

 in abundance. 



Lead has been explored at three places in this county — the 

 Rossie, the Black Lake, and the Wilson vein. 



" The rock in which these veins are found is gneiss, interlaminated 

 with hornblende. The gangue is carbonate of lime, coarse and crystalline, 

 with druses of beautiful calcareous spar. The dip is nearly vertical, 

 slightly inclining to the north, as may be seen by the diagram exhibiting 

 a view of the eastern termination of the vein, as it was when first ex- 

 posed by the removal of the rubbish concealing it. The whole width 

 of the gangue is four feet. The whole depth to which the mine has 

 been worked, is 100 feet. At the depth of 40 feet, the average width 

 of the vein of lead, is 2^ feet ; at 80 feet, 3 feet ; and at 100 feet, SI feet ; 

 showing a gradual increase in width. It is to be understood, that there 

 is not a width of solid galena of 3, or even 2 feet; but the width at which 

 the lead appears in the vein of spar, is as stated at the various depths. It 

 is every where more or less intermixed with the gangue, even when it is 

 the richest. It is considered, that a vein, 1 foot in width, having the 



