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PROFESSOR HEDDLE ON THE MINERALOGY OF SCOTLAND. 475 
minute crystals, forms the general mass of the rock ; this, it will be seen, is 
true in a certain sense; but it is certainly not the case that a mineral with a 
bronzy true-hypersthene lustre forms the general mass of the rock. The 
mineral which does so is brown and rusty externally, of vitreous lustre, and 
dark green internally when fresh. It is, in fact, perfectly similar to the 
variety to be seen in the ordinary rock of Rum; and specially in the more 
central, somewhat lower range of Baikeval, Arstival, and Tralival. Every 
feature of the two rocks is the same, only that they are somewhat heightened 
as regards roughness, sonorous ring, and sterility, in this portion of the latter 
island. Bare and rugged as the Cuchullins are, there is no spot in them which 
even approaches in these respects to the ridge of Tralival ;—JAmzson speaks of 
this part of the island as “terrible, bare, rugged ;”—MAccuLLocu says “ Rum is 
the wildest and most repulsive of all the islands.” 
But it can be shown that, accurate and cautious as an observer as Dr 
MAccUuLLocn was in the mineralogical department of his science, he was hasty 
in founding a species upon such characters as he observed in this mineral; and 
still more hasty in naming a great mountain mass therefrom. 
_ The marked feature insisted on in the mineral is its bronzy lustre ; it con- 
ferred upon the rock which it goes to form its own name, from a supposed and 
assigned unusual resistance tothe blows of the hammer. 
Now it has to be maintained that it is not consistent, ordinarily practicable, 
or proper to characterise or confer upon a new creation a name which shall be 
expressive of the features which it displays during the period of its dissolution 
| and its decay. Yet this is just what Dr Maccuttocy has in this case done; and 
| moreover that which, in his acting designedly and expressedly in the same way 
as regards the mineral found in the Scuir More of Rum, he laid down as the 
| principle of his nomenclature. 
I have to maintain in the first place that the bronze-lustre which has been 
| assigned as the characteristic appearance of this mineral is only to be seen in it 
| during its decay; and in the second, that the toughness assigned to it in its 
Name is neither characteristic of it, or a feature of it at all—but only of the rock 
mass which it goes to form. If in addition I can show that its composition and 
properties are identical with those of a well-known mineral, it can have no 
| claim whatever to a title which expresses specific individuality. 
The bronzy or semi-metallic lustre is only to be seen in weathered specimens, 
and it only extends in them to a depth commensurate with the amount of their 
weathering. 
_ The specimens which most markedly of any that I have seen exhibited the 
somewhat bronzy lustre—and in these there was even a slight amount of the 
 jviolaceous hue typical of true Paulite—were given me by Principal Forsss. 
The analysis of these is given; they were from Hart o’ Corry. . The bronzy 
_ |portion occupied a layer certainly not the twentieth of an inch in thickness ; 
