les), Autun, etc., boghead have shown us merely a
yellowish-brown amorphous mass holding in suspension lens-shaped or
radiating floccose masses which it is scarcely possible to refer to any
known vegetable organism.

Among the theories that we have cited in the beginning, the one that best
agrees with the facts that we have pointed out is the third, which would
admit, then, two things in the formation of coal. The first would include
the different chemical reactions which cannot yet be determined, but which
would have brought the vegetable matter now to the state of soft coal
(with its different varieties), and now to the state of anthracite. The
second would comprehend the preservation, through burial, of the organic
matter in the stage of carbonization that it had reached, and as the
result of compression and gradual desiccation, the development of the
physical properties that we now find in the different carbonized
substances.

We annex to this article a number of figures made from preparations of
various coals. These preparations were obtained by making the fragments
sufficiently thin without the aid of any chemical reagent, so as to avoid
the reproach that things were made to appear that the coal did not
contain. This slow and delicate method is not capable of revealing all the
organisms That the carbonaceous substance contains, but, per contra, one
is riot absolutely sure of the pre-existence of everything that resembles
organs or fragments of such that he distinguishes therein by means of the
microscope.

Our researches, as we have above stated, have been confined to different
cannel coals, anthracite, boghead, and coal plants isolated either in coal
pebbles, or in schists and sandstones.

[Illustration: 12a: FIG. 1.--Lancashire cannel coal; longitudinal section,
X200.]

[Illustration: 12b: FIG. 2.--Lancashire cannel coal; transverse section,
X200.]

Figs. 1 and 2 (magnified two hundred times) represent two sections, made
in rectangular planes, of fragments of Lancashire cannel coal. In a
certain measure, they remind one of Figs. 4 and 5, Pl 11, of Witham's
"Internal Structure of Fossil Vegetables," and which were drawn from
specimens of cannel coal derived likewise from Lancashire, but which are
not so highly magnified. There is an interesting fact to note in this
coincidence, and that is that this structure, which is so difficult to
explain in its details, is not accidental, but a consequence of the
nat