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TRY A MINERALIZED
PAVEMENT.
The suggestion of our worthy Mayor,
that Broadway
be repaired with granite upon a bed of concrete, has elicited much
comment
from the press, and the whole interminable topic of street-pavement
seems
fairly to be revived.
With all deference to the more
matured opinions of
our contemporaries, we wish to say a few words, or rather to insinuate
a few queries on the subject ourselves; and we shall put our
observations
in the shape of addenda to the valuable hints published by us a
few days ago, and for which we were indebted altogether to a
well-informed
friend who has had especial opportunities of coming to a just
conclusion
in respect to the matter at issue.
His plan, it will be remembered, had
reference chiefly
to the manner of arranging wooden blocks — to the proper inclination to
be given to them, with the object of preventing the two evils of swagging,
or floating in wet weather, and of decay. The suggestions were highly
ingenious,
and for the purposes contemplated the pavement of our friend seems
decidedly
superior to the overlapping and riveted roads, called stereotomic,
which
for some years past have been the subject of experiment at Paris.
In that city the wooden blocks have
been found, with
slight exception, to remain sufficiently firm at all seasons;
but
there, as here, the insuperable difficulty has been decay, a
difficulty
which, as far as we can understand, has been only very partially
overcome,
either by stereotomizing the blocks, or depositing them with their
pores
inclined from the perpendicular.
There can be no doubt in the world
that a very durable
and excellent pavement can be formed of rudely wrought eighteen-inch
cubes
of hard stone, with the upper surfaces roughened, and the whole laid
with
merely common precaution as an ordinary brick trottoir. Where
this
experiment has been tried, it has met with the fullest success. The
objections
are, first, its cost, which, if the proper stone be employed, is very
great;
and secondly, the street din, which it does not obviate
to
a sufficient extent. The former objection is scarcely one at all, where
funds are at command, for in the end it is infinitely the cheapest
pavement
which can be contrived by man; all the expense is in beginning; repairs
will very rarely be needed. But the second objection is one of a vital
importance, which we regret to perceive that our authorities are in
some
danger of overlooking. The loss in time (to say nothing of
temper)
through the intolerable nuisance of street-noise, would astonish all
thinking
people, if tangibly and mathematically put. We need say
nothing,
of course, about the vast inconvenience, and often fatal injury, which
it occasions to invalids.
It is admitted on all hands that, as
long as they
last, the wooden pavements have every advantage over all other
pavements
which have been contrived. They make little noise; they are easily kept
clean; they save a vast deal in horse-power; they are pleasant to the
hoof;
and in the wear and tear of vehicles save at least twenty per cent.
Much
may be said, too, of the economy of time, through the increased
rapidity
of passage to and fro.
The first objection is that of injury
to the public
health, through the miasma from decaying wood; but as this point is
involved
in decay itself, we may dismiss it and speak of the latter alone.
There is nothing in all experimental
philosophy which
has been more unequivocally demonstrated than the fact that, by a very
simple process, even the greenest wood may be preserved for centuries,
from decay. To test this, blocks, properly prepared, were subjected,
for
three years, in the fungus pit of the dock-yard at Woolwich, to all the
know decomposing agents which can ever naturally be brought to act
against
wood, and at the expiration of the period, these blocks were found as
perfect
in every particular as when originally deposited in the pit. A thousand
similar experiments have had identical results. The fact is
established.
The preservative principle is that of
mercury, and
it is most readily employed in the bi-chloride (corrosive sublimate.)
Let
a pound of sublimate be dissolved in sixteen gallons of water, and a
piece
of even the sappiest wood (not rotten) be immersed in the
decoction
for seventy-two hours, and the wood cannot afterwards be rotted.
By injection in vacuo the mineralization can be effected instanter.
The cost of the bi-chloride of
mercury is, we presume,
at present, something less than a dollar per pound, at retail, and at
present.
Should demand arise, however, to any considerable extent, quicksilver
mines
now unworked would be forthwith put into operation, and we should soon
get the article for thirty or forty cents. The cost of mineralizing our
pavements, under such circumstances, would be trivial indeed. It would
be trivial even now. Decay being arrested, the public ill-health
resulting,
or said to result, form such decay, is of course to be left out of the
question; and lest some of our fanciful friends may imagine that ill
consequences
might arise from the mercurial effluvium, we take occasion to
state
that no perceptible effluvia arise, and that repeated
experiments
in the close holds of mineralized ships, have demonstrated that
no apprehensions on this score are to be entertained.
Now the only question in the matter
which seems to
us unanswerable, is the simple one — "why has not the mineralizing
process
been adopted in the preparation of the wooden blocks with which we have
so frequently experimented in the pavement of our streets?"
But perhaps it has; and
perhaps we are only
evincing our want of information in regard to the municipal affairs. If
so, we shall rejoice to be set right — if not so, we shall be
equally
glad to hear the arguments which are advanced in objection to
experimenting
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