344 GEOLOGY OF THE SECOND DISTRICT. 



ordinary changes or phenomena of the great field of nature, but it takes place under our eyes 

 in the laboratory, and in various manufacturing operations. But the first part of the hypothesis 

 seems entirely unsupported by facts ; and inasmuch as the real facts and phenomena are 

 opposed to it, I have been led to adopt views at variance with tliosc of my colleague. 



The last part of the hypothesis contained in the foregoing extract, viz. that the specular 

 oxide is more intimately connected with the potsdam sandstone than with the primary rocks, 

 will require but one or two remarks ; for if the views I have expressed are founded on fact, 

 then the connection of the ore with the potsdam sandstone is wholly accidental. 



We find that most of the beds of specular oxide, as the Tate and Policy beds or veins, are 

 wholly disconnected with this rock ; they are contained in gneiss ; they are wholly mined in 

 gneiss, and are not taken ofi' from the primary surface, as they would be if deposited upon it 

 immediately preceding the era of this sandstone. These are the facts as it regards connection 

 with this rock. I infer, therefore, from these and numerous similar facts, that there is no 

 necessary connection at all, but where there is a connection, it is accidental ; and furthermore, 

 the whole mass, with the ore and limestone, are essentially primary in their characters and 

 position. That the masses reached the surface subsequent to the consohdation of the pots- 

 dam sandstone, I believe is a point which may be sustained by facts ; but it is unnecessary to 

 dwell upon it, as the facts themselves which go to support it have been already given. 



So much space and time would not have been consumed upon these questions, if they were 

 merely theoretical ; but inasmuch as they are truly practical, and in this view highly impor- 

 tant, it seemed necessary that we should know where to look for, and how to mine this species 

 of iron ore. If they are deposited upon the primary platform, then certainly we need not 

 e-xpect to find them in the midst of the primary masses : we must pursue them upon that 

 surface. This too will modify our views as it regards their permanence ; and on this point, I 

 agree with my colleague that they are less certain, and more liable to fail in quantity than the 

 magnetic oxides. My reasons, however, are different from his ; and while I believe these 

 ores are always connected with masses within the primary crust, I by no means suppose that 

 this connection may be demonstrated in every case. For instance, a mass of ore is entirely 

 removed, and this removed part may have been connected with a larger mass ; but this con- 

 nection is now severed, and nothing remains to show its existence. If, however, the specular 

 oxide is a local deposit in tufa or marl, then the whole deposit may be removed, and we have 

 no prospect of finding it in the form of a vein in the primary rocks. 



A very large proportion of the ore of the Parish and Kearney veins or beds is in the form 

 of red stony matter, and often passes into the pulverulent state : in this condition, it is very 

 unlike the crystallized specular oxide. The shape or form of either of these collections of 

 ore has not yet been distinctly shown in the workings. They resemble superficially large 

 masses, and originally covered quite an area ; but in the present workings, the excavations 

 descend into the primary rocks. I was unable to find lateral walls, or the precise extent of 

 the masses on either hand. Below the southern angle of the Parish vein, the workmen had 

 encountered a mass of shaly serpentine. In this rock \ could not observe the continuance of 

 the ore, but it appeared to rest upon it at this particular part of the mine. Serpentine, how- 



