Staunton spectator. [volume] (Staunton, Va.) 1849-1896, 1853-08-03
For The Spectator.
Blue Ridge Tunnel.
BRooKsvlLLE, July 2Sth, lS5

DROOhS'iLLE, July ~Oth, iOoo'
.Nfesws Editors:-I see in your ever decorous
columns Of Yesterday, short extract Of two very
long articles which appeared lately in the Win
chester Virginian relative to Tunnels, and which
| have some reasons to hope are not editorial /,
though apparently So
You are mistaken in calling this controversy
the publications of the writer in the Winchester
Virgnan do not allow of any controversy; they
are overwhelming evidences and crushing concia-
sons. In the first pubiostiea the writer proves,
by incontrovertible calculations, that was in er-
ror in stating that the height of the mountain a
bove the Tunnel is 700 feet, and that it is, in re-
ality | $50 feet: will revise my notes and lev
cling operations.
had imagined that the length of a tunnel had
less to do with the time necessary to complete It's
excavation, than the depth of its longer shafts
because it seemed to me that, when these are
down, it must take but little time for the horizon
tai drifts from shaft TO shaft to meet and that con-
seuuently, whatever the length might be, the time
of completion would be the same for the same
leneth of shafts when tunnels can be 50 subdivld-
ed. Under this, it appears, erroneous impression,
considering that the Woodhead tunnel in England
..thIou5h milestone grit" with shafts 600 feet deep
and the Marseilles tunnel, With its "A shafts,some
of them also 600 feet deep, both quoted by the a
bove unknown writer, had each taken five years
in their construction, thought myself justified In
the conclusion that the Blue Ridge Tunnel AT a
depth of 700 feet, through not "milstone grit but
the hardest of trap rock and solid flint might pro-
baby take fully as long; and, as could excavate
it in the same time, without shafts, naturally
concluded that it would be as well for me 10 save
the useless expenditure of sinking them.
But all this was, it seems, mistaken view OF
the question: the article referred to- dwei4s on the
principle that the time for excavatng tunnels
should be calculated in proportion OF their lengths,
which would fix the time here at the ratio OF four
6fths Of mile to miles; that is at about 10
months with how many shafts is not mentioned
hut probably with or S of them.
Another error had fallen into: thought the
sinking Of shafts difficult and slow business:
based nv opinion on facts. which must have been
misrepresented. Frederick Waiter Simms, En-
cineer of the Blechingley tunnel, England, in his
T,noble account ofthis work states that the shafts
through blue clau, commenced in the beginning
August, reached their depth at the END OF octo
Der; the deepest was scarcely 90 ieet down lhl'
would appear TO be about one loot per Gay TINS
eminent Engineer has undoubtedly. erred In ms
publication for, the author OF the tTglh,ah sfu
Gle states the progress at Clio feet per DAY
Again had relied on the statements OF bro
Their engineer, employed on the Po'tsviie railroad
whom heretofore had considered reliable man
who furnished me with detailed account, IRON
which it appeared that the progress In "a hours
was. in the lst shaft 062 Of one foot, in the Sc
cond |. foot, in the Sd 066, in the 4th O.5b, II
the 9Th O.64 and in the 9th 06ej so that the max