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PROFESSOR F. D. ADAMS AND DR. J. T. NICOLSOX 
10 Marble. Lot 11, Range IV., Township of Burleigh, Ontario. —This is identical 
with No. 9, except that the base is very much finer in grain. The larger remnants 
are so highly twinned that they often present the fibrous appearance before referred 
to. They lie scattered about in the fine-grained base, and wedge-shaped tongues of 
the finer-grained material can often be observed penetrating them. The structure is 
identical with that seen in the Carrara marble when deformed at ordinary tempera¬ 
tures, that is, with a marked development of cataclastic structures rather than of 
movement on gliding planes. The whole in the case of the natural marble, however, 
is on a larger scale ; the original rock was more coarsely crystalline, and the resulting 
product was not so finely granulated. 
11. Marble. Lot 38, Range VIII ., Township of Anstruther, Ontario. —Practically 
identical with 10 in every respect. A microphotograph of a thin section of a highly 
granulated portion of this rock is shown on Plate 25, fig. 4. It is photographed 
between crossed Nicols in polarised light and is magnified 70 diameters. 
12. Marble. Lot 29, Range XI., Township of Cardiff, Ontario. —A very fine¬ 
grained marble, through which are distributed occasional large twisted calcite 
remnants, which indicate that the rock in its present form has resulted from the 
granulation of a coarsely crystalline marble. The rock bears a very strong resem¬ 
blance to No. 4, but the granulation is more advanced and the calcite remnants less 
numerous. The granulated portion of the rock is also identical with that of No. 10 ; 
in fact, No. 10, if more completely granulated, would be identical in character with 
this rock. 
13. Limestone. Lot 28, Range XL, Township of Monmouth, Ontario. —At two 
places in this township (Nos. 13 and 14) the coarsely crystalline white limestone of 
the Laurentian contains somewhat irregular-shaped streaks or bands which are bluish- 
black in colour and very fine in grain. These are portions of the original limestone in 
a conqmratively unaltered condition. In these bluish-black portions the calcite 
grains are very small, and have the dark carbonaceous colouring matter distributed 
all through their substance. An enlargement of 500 diameters is required for their 
study. With this power the rock is seen to be perfectly crystalline, the minute 
calcite individuals being fitted together along boundaries which are smooth or in some 
cases slightly crenulated. The grains are usually distinctly flattened, but this is not 
seen in all cases. Some of them are twinned, and many of them show strain shadows. 
The white marble with which this blue limestone is associated consists of a much more 
coarsely grained aggregate of calcite grains. These show the most marked evidence 
of motion, being very much twisted and flattened in the direction of the foliation of 
the rock, with twinning and very pronounced strain shadows. The carbonaceous 
pigment has been destroyed. Distributed in the usual more or less rounded forms 
through both the blue and the white varieties, but especially abundant in the latter, 
are grains of several other minerals—plagioclase, pyroxene, biotite, &c.—the results 
of metamorphic action. These generally show the effects of pressure, often in a 
striking 1 manner. 
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