

VALUE OF LIGNITES AND IRONSTONES. - 193 
413. The lignite from Rainy River, to which the last analysis refers, 
is noticed in the paragraph indicated above. The specimen received was 
asmall one; and not having visited the locality, I cannot speak confi- 
dently as to the mode of its occurrence. In its appearance and composition 
it resembles many of the lignites of the Tertiary, but if in situ, it may 
more probably be found to belong toan outlyer of Lower Cretaceous rocks. 
In any case, it is far removed from the regions to which the other analy- 
ses refer, and does not at present require further consideration. | 
414. The mineral fuels met with in the neighbourhood of the Line, 
fall naturally into two distinct categories. The first, including all except 
one, must be called lignites ; the second, represented by a single example 
only, is a true bituminous coal. The first class includes not only, there- 
fore, the great majority of the fuels met with in the vicinity of the forty- 
nith parallel, but also almost all known in the interior region of the con- 
tinent, both north and south of this line. They are emphatically lignites 
or brown coals, and though they may be designated by the name lignite 
coal, insomuch as they come under the generic class of coals, they cer- 
tainly cannot properly be named by the latter word alone, as by it an en- 
tirely different kind of material is generally understood. The vast area, 
and great importance of these beds of fuel, should not be allowed to 
weigh in changing the name which would without any hesitation be ap- 
plied to them, were their occurrence on a more limited scale. The word 
lignite has attached to it a definite mineralogical significance, and must be 
employed when it is desired to define the position of these fuels in the 
scale of combustible materials. Lignites are found in connection with many 
of the later geological formations, and differ from true coals in containing 
a larger percentage of water, hygroscopic and combined, a greater propor- 
tion of hydrogen, oxygen and nitrogen, and less carbon. They also inva- 
riably give a brown streak or powder, yield easily a brown solution with 
caustic potash, and sometimes even to water, and, according to Frémy, 
may also be distinguished from coal and peat by their complete solubi- 
lity in nitric acid and hypochlorites. The better kind of Tertiary lignites 
of the region now in question, differ from many foreign fuels of the same 
class, in their small percentage of ash, but show for the most part distinct 
evidence of having been produced from wood, and would therefere even 
be classed as lignites under the most restricted meaning of that term. 
The wood, from its microscopic structure, has been coniferous, and may 
have belonged to the same species of Thuya, Sequoia, ete., represented by 
leaves in the associated clays. | 
