The Cairo bulletin. [volume] (Cairo, Ill.) 1872-1878, 1878-01-17
NOTICE TO CONTRACTORS.
OFFICE OF CITY CLERK,
- L. III L. D 40

Off VI Stl NbERh,
Cairo, Ills, Jan. 3, 1878,
Sealed proposals will be received at this
office, directed to the city council of Cairo,
Illinois, until O'Clock Tuesday evening,
February 10th, A. ID. 1878, FOX the conetruc-
ton OF a one span iron bridge, together
with The approaches or abutments anu
LIQUIDATION, across Cache river, about one
and one ali miles from Mound City rail-
road depot, and four miles north OF the city
of Cairo, 10 the counties of Alexander and
Pulaski, state OF Illinois, according TO the
plans and specifications prepared by John
p. neiy, Esq, g. f., now on file and sub
ject TO examination IN this office, tue speci-
ications of which are 10 follows, viz;
Said bridge snd trestle work 10 be made
up OF eighteen QS) ops nings OF eighteen as
feet from centre to centre OF posts, and one
span OF one hun ired 200 feet across the
river bed.
The one hundred (i00) feet span tn be OF
iron, and so propOrtoned that Il load OF ten
ll0) tons distributed over twenty (a0) Hneal
teet at the centre Of the span, shall not
strain the iron over twelve thousand
" ,0U0) pounds per square inch tensile, or
over seven thousand five hundred & 800
pounds per square inch shearlng strain
the strain in compression to be IN at,
least in the proportion to the ratio OF
length to diameter, by Gordon's formula.
The span OF said bridge to be one hur-
dred 400 feet in the clearand the roadway
twelve az feet wide.
The floor TO be OF white oak plank two
and one-halt GU inches thick and not over
| twelve az inches wide.
The floor beams to be OF white oak and In
proportion to the balance Of the one hun.
died OC0) feet span structure, and also "a
| be provided with u 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 irO1
span TO be placed on 0 mud sill EMP, TWEEN.
" COZ feet long morticod aud tenoned tn d
sufficient number Of white oak piles, firm.
| ly driven into the river bank.
| TREs1LK WORK.
The bents to be formed ottour posts lOXit
| inches square, the two inner parts to stanc
perpendicular and the two outer parts Il
DO framed and stand ut batter Of one IL
eight. The cap and sill OF the bents to b,
l2Xl2 inch square timber, TIE caps TO b,
twenty (2Dl feet long, and the sills to pro
lee, on each end two feet past the cute
edge of the outside posts. The posts to b.
mo ',iced and tenoned into the caps and stills
and each tcnon TO be pinned with tw
tbree-quarter q inch square iron pirs, an
each bent to DO braced by two dngona
. braces OF l2X2l inch plank, well lttc d an
spiked on caps, posts and sills.
The bents to rest or stand upon four mu
sills l2Al2 inches and eight (s) teet long "a
10 the ground and placed on the alIgnmer
of tho work.
, The carriage way OF the :tres,lework {
be sixteen (lb) feet wide, The floor plan
o be thee t3) inches and not over lively
4, Q?l inches wide, aud to be well spiked o
TO the stringers and floor beams.
The hoor beams to he made up az follows
: two 81 stringers of sXl2 inches set on III
caps and sixteen (l0) ieet apart from gu
=. side to outside. The space between sal
a stringers to he equally divided for seye
, % beams of 3Xl2 inches each and each \,
Of moor beams or spans TO have three t.,l NJ,
. OF her inlbono bridging Of 2Xi inch scan
. ling.
The s,riDgeIs and Moor beams to rest
! least Xix (6) inches on be caps.
The etfingars TO connect by half JON
and TO be- fastened to the caps sy one inc