424 Observations, 5'c. on the Papyri 
nearly in as large a proportion as the vegetable matter, and they 
were light, and the layers easily separated from each other. A 
number of darker brown ones, which, from afew charaeters dis- 
covered in opening them, appeared to be Latin MSS., were ag- 
glutinated as it were into one mass; and when they were opened 
by introducing a needle between the layers, spots or lines of 
charcoal appeared where the folds had been, as if the letters 
had been washed out by water, and the matter of which the 
were composed deposited on the folds. Amongst the black 
MSS. a very few fragments presented leaves which separated from 
each other with considerable facility, and such had been for the 
most part operated upon; but in general the MSS. of this class 
were hard, heavy, and coherent, and contained fine voleanic dust 
within their folds. Some few of the black and darker brown 
MSS., which were loose in their texture, were almost entirely 
decayed, and exhibited on their surface a quantity of brown 
powder. 
The persons to whom the care of these MSS. is confided, or 
who have worked upon them, have always attributed these dif- 
ferent appearances to the action of fire, more or less intense, ac- 
cording to the proximity of the lava,which has been imagined to 
have covered the part of the city in which they were found: but 
this idea is entirely erroneous, that part of Herculaneum being, 
as I satisfied myself by repeated examinations, under a hed of 
tufa formed of sand, volcanic ashes, stones, and dust, cemented 
by the operation of water (probably at the time of its action in 
a boiling state). And there is great reason to conclude, that the 
different states of the MSS. depend upon a gradual process of 
decomposition ; the loose chesnut ones probably not having been 
wetted, but merely changed by the re-action of their elements, 
assisted by the operation of a small quantity of air; the black 
ones, which easily uuroll, probably remained in a moist state 
without any percolation of water; and the dense ones, con- 
taining earthy matter, had probably been acted on by warm wa- 
ter, which not only carried into the folds earthy matter. suspended 
in it, but likewise dissolved the starch and gluten used in pre- 
paring the papyrus and the glue of the ink, and distributed them- 
through the substance of the MSS., and some of these rolls had 
probably been strongly compressed when moist in different po- 
sitions. 
The operation of fire is not at all necessary for producing such 
an imperfect carbonization of vegetable matter as that displayed 
by the MSS.: thus, at Pompeii, which was covered by a shower 
of ashes that must have been cold, as they fell at a distance of 
seven or eight miles from the crater of Vesuvius, the wood of the 
houses is uniformly found converted into charcoal; yet the co- 
lours 
: 
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