[BAILEY] OCCURRENCE OF THE MINERAL ALBERTITE 79 
through the wear of older deposits, and the only plausible explanation 
would be their derivation from either injections or infiltrations of petro- 
leum, subsequently altered into Albertite. In other cases, as on Peck’s 
Creek, the mineral, though in similar conglomerates, appears, according 
to Mr. H. B. Goodrich, to whom I am indebted for a specimen and for 
particulars, to occupy a fissure of much later origin. In this case the 
fissure filling, having a width of about eight inches, consists of bodies 
of Albertite, sometimes angular and sometimes broken, in a gangue 
or matrix of calcite, pyrites and crushed country rock. 
(3) In green chloritic schists. A deposit of this character occurs in 
Mechanic Settlement, twenty miles distant from the Albert mines, and 
has been described in the Geological Survey Report for 1878-79. It 
was largely from the facts here observed that Prof. Hind, in 1865, was 
led to advance the view that the source of Albertite was to be looked 
for, not in the bituminous shales of the Lower Carboniferous forma- 
tion, as then understood, but in the slates or older rocks which were at 
the same time referred to as probably Devonian. It is, however, to be 
observed that not only is there no evidence to show that any Devonian 
rocks other than the Albert shales, if indeed these are Devonian, occur 
in the vicinity, the slates holding the Albertite being probably of 
Cambrian or Huronian origin, but, as shown by Dr. Ells, they have 
associated with them a conglomerate, largely made up of their waste, 
and probably of Lower Carboniferous age, in which Albertite is mucn 
more abundant, and which, with the slates probably derived its supply 
of hydrocarbons from an overlying mass of shales now removed. 
A somewhat similar mode of occurrence has been observed by Mr. 
H. B. Goodrich on Peck’s Creek, the mineral being here found in 
metamorphic quartz schists, partly in the form of plates in minute 
joints, of about the thickness of paper, and partly in specks that appear 
to be isolated. Again at a second locality (Martin’s farm) in Mechanics 
Settlement, granitoid rocks underlying Lower Carboniferous sediments 
are described as impregnated to the depth of an eighth of an inch with 
bitumen, while the numerous joints which intersect the rock are also 
filled with particles of Albertite. It is very significant, as regards both 
the source and the original condition of the latter that it is never found 
very far from Devonian or Lower Carboniferous sediments, and that 
when met with in older rocks it is confined to the surface of the latter 
and to the cracks or joints by which these are pervaded. 
(4) In Gypsum. This very singular mode of occurrence of Alber- 
tite has been observed only within the last few years, and for the facts 
as well as the illustrative specimens I am indebted to Mr. C. J. Osman, 
M.P.P., manager of the Albert Manufacturing Company. From that 
