212 T H E PA S SA G E O F H A N N IB A L .
i
and these seams are often so close as to be
nearly imperceptible, and quite impervious
to air or water. By taking advantage of
such seams, and making the borings in
them, a small degree of expansive force
would rend large masses of rock, as they
split with great facility along the cross
seams, which are the natural cleavages, and
are nearly as regular as those of a rhom-
boidal crystal of calcspar.
1 am inclined to believe that Hannibal,
whose mind was so fertile in resources,
might be acquainted with the power of compressed
vapour, or gas, in bursting masses
of stone, and that he employed vinegar,
not as a chemical agent to dissolve the
projecting masses of rock that obstructed
his progress, but to act mechanically in
rending them, either by the evolution of
gas, by the expansion of vapour, or by the
force of both these agents conjointly. It
is indeed difficult to conceive how such a
story as that of dissolving the Alps with
vinegar, could have originated without
some foundation in fact; but facts, imperfectly
understood, have not unfrequently
been transformed by historians into prodigies,
which have maintained credit for ages,
t h e P A S S A G E O F H A N N I B A L . 213
and at length are rejected as fabulous, until
circumstances are discovered which elucidate
the obscurity of history, and enable
us to separate truth from error.*
* At the place where the above remarks were written,
I tiad no opportunity of consulting Livy : on a reference
to that historian, I find that he informs us Hannibal
employed vinegar to open a passage on his descent
into Italy, soon after he had crossed the summit of the
Alps ; but the whole narration of this remarkable expedition,
as given by the Roman historian, though replete
with poetical imagery, is destitute of all the features of
individual locality, which might serve to point out the
line of route to future travellers. On this account he
is not to be compared with Polybius, who wrote at a
period much nearer the time of Hannibal’s expedition,
and who had travelled over the whole route himself.
Livy thus describes the rock, and the mode of dissolving
it: “ Ventum deinde ad multo angustiorem rupem ;
atque ita rectis saxis ut segre expeditus milites tenta-
bundus, manibusque retinens virgulta ac stripes circa
eminentes demittere sese posset. Natura locus jam ante
prseceps, recenti lapsu terrm, in pedum mille admodum
altitudinem abruptus erat. Ibi quum velut ad finem
vise equites constitissent, miranti Annibali qum res mo-
raretur agmen nunciatur, rupem inviam esse.” “ Inde
ad rupem muniendum, perquam unam via esse poterat,
milites ducti quum csedendum esset saxum, arboribus
circa immanibus dejectis detruncatisque struem ingentem
hgnorum faciunt : (quum vis venti apta faciendo igni
coorta esset,) camque succendunt, ardentiaque saxa infuso
aceto putrefaciunt. Ita torridam incendio rupem
ferro pandunt, molliuntque anfractibus modicis chvos.
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