The Cairo bulletin. [volume] (Cairo, Ill.) 1872-1878, 1878-01-26
NOTICE TO CONTRACTORS.
OFFICE or CITY CLERK,
Cairo, Ills, Jan. 3, 1873,


Sealed proposals will be received at this
office, directed to the city council of Cairo,
Illinois, until O'Clock Tuesday evening,
February Mb. A. ID. 1878, for the construc.
ton OF a enc span iron bridge, together
with the approaches or sbutments and
foundation, across Cache river, about one
and one. halt miles from Mound City rail-.
road depot, and four miles north OF the city
of Cairo, in the counties Of Alexander and
Pulaski, state Of Illinois, according TO the
plans and specifications prepared by John
T. Hely, Esq, Z. f., now on file and sub
ject to examination IN this Office, the speci.
1ications Of which are ~ follows, viz:
Said bridge and trestle work 10 be msde
up of eighteen (:s) openings OF eight en- tiSl
feet from centre 10 centre Of posts, and one
span OF one hun ired 200 feet across the
river bed.
The one hundred 900 feet span to be OF
iron, and so proportioned that q load OF ten
,l0l tons distiibuted over twenty t20) lineal
feet Of the centre OF the span, shall not
strain the iron over twelve thousand
| IL, 900 pounds per square inch tensile, or
over seven thousand five hundred & 5n0)
pounds per square inch Shearing strain
the strain in compression TO be IN at,
least in the proportion 10 the ratio Of
length to diameter, by G0rdon's formula.
The span Of said bridge TO be one hun
bred (l00l feet in the clear and the roadway
twelve 12) feet wide.
The floor TO be OF white oak plank two
and one-half (2t) inches thick and not over
twelve (l2) inches wide.
The floor beams to be OF white OAK and In
proportion to the balance Of the one hun.
| dred AGO. feet span structure, and also TO
| be provided with suitable axle guard.
! The above to rest upon iron columns pro-
portioned 10 the structure TO be supported,
| the columns at each end Of the bent or iron
span TO be placed on mud sill i2Xl2, twen-
| ~ COY feet long morticed and tenoned to
sufficient number Of white oak piles, Grm.
| ~ driven into the river bank.
| TREsTLE WORK.
| The bents to he formed Of four posts l0XlN
inches square, the Two inner parts TO stand
perpendicular and the two outer part. to
pe framed and stand at batter Of one In
eight. The cap and sill OF the bents TO be
l2Xl2 inca square timber, tle caps to be
twenty (20) feet long, and the sills to pro-
Jet on each end two ieet past the outer
| edge of the outside posts. The posts to be
morticed and tenoned into the caps and stills,
and each tenon TO be pinned with two
each bent 10 be praced by two diagonal
braces OF loX23 inch plank, we'll titts q and
spiked on caps, posts and sills.
The bents TO rest or stand uoon four mud
stills 1aXl2 inches and eight (S) feet long set
in the ground and placed on the alignment
of the work.
The carriage way OF the .trestlework to
be sixteen (l6) feet wide, tho floor plank
70 be THE (3) inches and not over twelve
lO inches wide, and TO be well spiked on
TO the stringers and floor beams.
Tie floor beams TO be ms de up as follows
two (2) stringers Of SXl2 inches set ON the
caps and sixteen (l8) feet apart from out.
side to outside. The space between said
stringers to be equslly divided for seven
% beams OF 3Xl2 inches each and each set
Of floor beams or spans TO have three (S) sets
OF herfingbons bridging Of 2X4 inch scant-
ling.
The stringers and floor beams 10 rest at
least Fix 81 inches on The caps.
The stringers TO connect by half JOINTS
and 20 be fastened 70 the caps by one inch
round spikes or bolts eighteen Qs) inches
long.
A railing or ballsstcrs four al feet high
10 be constructed on each side OF above dis.
cribed trestlework. The posts TO be Axe
inch clees and braced on the caps and fasten-
ed on 10 the stringers by two (2) one.hali
inch bolts. The parts to he six (G) fee,
apart: the hand rail 2Xi inches. and an
axle guard of2A inches, all well fastened
on 10 the posts.
All OF the above timbers TO be OF white
or burr oak Of best qua lily, and
the work done In q thorough and work
manlike manner, and under the supervision
Of such person as the committee on sire cts,
or the city council OF the city Of Cairo may
designate,
. The approaches to above trestlework and
bridge to be of earth and with a slope oil
not more than one In ten and not less thar
sixteen (l6) feet wide on top, with slope
! 10 the base OF one In two, Separate bid!
will DO received for iron span, including
abutments and foundation, for the wooden
trestle portion OF said bridge, and for The
earthen approaches, or for the entire
9 work.
The right TO reject any Or all bids, is re
, served. J. b. PHILLIs,
dtd. City Clerk.
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