﻿Prof. How on the Mineralogy of Nova Scotia. 265 



galena would involve some secondary action. The deposits are 

 not thought to be of mining- importance, except in two instances, 

 in which the ores of copper are considered to exist in promising 

 quantities : in one of these, indeed, lately discovered there is 

 said to be a bed some feet thick ; a sample of the ore sent me 

 gave 29*5 per cent, metallic copper. 



I have not been able to find more than one complete ultimate 

 analysis of a lignite; this is one of the fourteen analyses given 

 by Dana*. In a minority only of the others is the existence of 

 nitrogen mentioned ; the quantity is given in no case but that re- 

 ferred to, the analysis of Vaux, who found - 57 per cent. From 

 this result and the following ultimate analysis of a lignite from 

 one of the deposits above mentioned, for which I am indebted 

 to Professor Anderson of Glasgow, it appears that the quantity 

 of nitrogen is somewhat less in this mineral than in black coal. 



The lignite selected for examination occurs in the carbonife- 

 rous district of Pictou county, with copper ore and common iron 

 pyrites. It is nearly black, and retains on some faces a fine- 

 grained woody structure, not very obvious to the naked eye, but 

 distinct under a glass : these surfaces are dull; those at right or 

 oblique angles are black, of almost resinous lustre, and without 

 structure : it is sectile, and easily broken into angular fragments 

 which receive polish under the burnisher. The mineral evidently 

 belongs to the variety of brown coal called jet. Boiled in potash, 

 it scarcely colours the fiuid. Ignited, it gives a transient feeble 

 yellow flame, and afterwards glows for a considerable time, evol- 

 ving the greasy odour often observed with lignite; in a closed 

 tube the product is chiefly water with a little yellowish matter ; 

 the vapours have an alkaline reaction. Ultimate analysis gave : — 



Carbon 74'5 



Hydrogen .... 4*3 



Nitrogen . . . . 1*0 



Oxygen 18'7 



Ash 1-5 



1000 



It does not appear that any inquiry has been made as to 

 whether lignites vary in composition according to their geolo- 

 gical age. As the circumstances under which they were formed 

 must have been analogous, the only differences to be expected at 

 the corresponding stages of conversion are those depending on 

 variations in the original material. Hence nothing like strict 

 comparison can be made; the following, however, is not without 

 interest. The large deposits of brown coal found in Germany 



* Mineralogy, 5th edit. p. 758. 



