Evening star. [volume] (Washington, D.C.) 1854-1972, 1869-04-27

laid a; the northeast intersection Of Pennsyl.
wanna avenue and nth street ~es'.
The Nicolscr consists Off superstruc.ure cfone
inch plank coated with Tar ana an upper s;ra-
tuR OF blocks, without sections the blocks are
six inches long three ncnes thick, and from six
TO ten Inches wide. placed on end in rows from
curb 20 curb, with the broad face fronting mp
and down the street. and so arranged as to
break Joints. The rows are separated by strips
OF planks which have grooves three-Qusrters
of an inch wide and three in cn-s deep. These
grooves are filled with hot gravel. coal tar and
pitch, well rammed. The surface Is coated
with coal TAR, pitcn and sand. TINS pavement
also, in Philadelphia, New York, and Brook
" 10 some extent.
The Stcford is composed of Iron and wood.
The base is Of cast iron, made into sections OF
square yard, with q number Of cells;
blocks prepared by machinery and saturated
with tar are forced into the cells. The sections
are held together by means Of staples or clamps
and pins. The plan Of forming the sections
has been modified by more recent letters
patent 10 the inventor; metallic bands be-
The sections are placed on stringers two inches
thick, and six inches wide, laid rransversely to
the line of the street, At distance Of three feet
apart The whole is coated with hot tar and
sand.
IGyette is formed OF sections, each section
beng composed of blocks Of wood Joined
together by means of rods or bolts running
through them transversely. The sections are
locked together by means OF tongues and
grooves; the tongue of one section fitting into
one section IL communicated 10 the others
In the sections the outer blocks are two or
more inches longer than the centre ones in
order that they may become embedded in the
sand foundation and thus secure stability.
Tie Reda consists of a sub-structure and
sectional upper stratum. The sub-structure Is
made by laying planks longitudInally on the
street, the ends resting on transverse
stringers. The upper stratum consists of
blocks six inches long and three inches So uare.
fastened together by wooden piEs or bolts; the
koys
which fit into grooves in the sides of the Sec
tons; the sections inierlock with each other so
as 10 prevent their becoming displaced. and at
the same time give lateral support. In laying
this pa vement. the blocks composing the Sec
tons, the pms, the keys, and the various parts
of the substructure are thoroughly saturated
with hot tar: the grooves on the surface
filled with hot gravel and pitch well rammed
and the whole coated with sand. The surface
into the cutters. whence il is carried into the
sewers. leaving The streets clean. The sections
OF both substructure and upper stratum can be
so arranged as TO size, &c, as to admit of the
whole being easily taken up and replaced
without interfering with the uniform grade
II affords good foothold for horses, and is
smooth and pleasant for travel. The grain OF
wood being exposed TO the surface it wears
less than granite, and will last longer without
repairs than any stone pavement. This pave.
ment can be laid at about - per square yard.
A small section Of Pennsylvaniania avenue,
near the Capitol, between LIST and I'd streets
west, has been laid with this pavement 1t
presents very excellent appearance and has
met with the appreciation Of all who have ia.
ken the trouble to examine it.
Having thus briefly described the principal
pavemeAts in use. and the manner OF laying
mem, Will proceed to consider which is best
adapted to this city.
After careful examination of the subject.
am OF opinion that good wooden pavement is
is free from dust, Of an even surface pre-.
sents less resistance to draught saves
tear and wear Of horses and vehicles, is disin.
asanitary point OF view, being water tight, and
can be arranged so as 70 span the dangerous
cutters which now exist at the intersection of
most Of our streets.
Stone pavements allow more or less in filtra.
ton OF water and decomposed vegetable mat.
ter, which finally escapes In the form OF
poisonous miasmata. There are many other
reasons which may be stated in favor OF wood.
The principle objection to 1T is want of dura.
bility. Read what Professor Mahan says on
this subject:-"The wear and tear of this kind
Of pavement (wooden) WILL in all probability,
be less than that OF stone" the celebrated
English Engineer, Sir John Burgoyne, SAYS
Wooden blocks, when placed with the end of
the grain exposed, wear less than granite" L
might cite other authorities In favor of the du.
rability OF wood, but deem II unnecessary, as
little consideration of the subject well serve
to convince the most skeptCal of the superb
GRITTY of wood as a paving material.
In every case where there Is friction and con-
cussion, wood is employed to act against iron
and steel. The use OF wood in pavements is
only an application Of the long accepted
principle that su distances OF dissimiIar nature
and hardness when brought together prevent
attrition, disintegration, wear, sc. The fine
sand and dust which are a source of annoy
ance where stone pavements are laid, get
caught by the tar coating on the surface OF
wooden pavement. are driven into the wood.
and converted into specle3 OF file.
After careful Investigation il appears 70 me
that the Ream Pavement is superior to any OF
the others. The Stow has no sections and no
substructure. The Nicolson has a substruc-
ture but no sections The Stafford is
composed OF wood and iron, has Sec
tons, but no substructure. The Fayette
has sections which lock by means OF tongues
and grooves, but no subs tructure. The Ream
has subsirncture and sections which lock
with each other by means OF grooves and
keys; il therefore differs essentially from auy
Of the others, and it is on account of this diff.
ference that recommend its adoption for use
n this city.
The carriageway of every street should have
convex surface, slopIng from center to curbe
al one in forty eight. or certainly not les than
TWO inches IN every ten feet. The curos
should be OF uniform grade with the center
OF the street The present inclination of foot.
walks, viz: half an inch In every foot, is suf.
ficIent for good drainage.
In conclusion would direct attention 10 the
miserable state OF our suburban streets. The
present system of laying thin coating ei
gravel over soft earth foundation is very OBJ.
Jectionable and a useless expense. If the streets
cannot be paved, sufficient space OF each
should be macadamIZsd. This could be done in
the following manner. Let the earth be levelled
anu well place thereon " layer OF SAND:
LEI this be moisteled. and also thoroughly
rammed: then add a coating OF broken stone,
or coarse gravel tree from clay and loam
the depth will depend on the amount of travel
This will form n road or street which when
consolidated Will not absorb much water aud
will AT all times present a hard a ad even sur.
face.
The deep cutters or bitches met with at the
interse ions of these streets should De filled up
widenec and paved. +. II. DoNEGAN G.. f.
Supt Of Streets, &c.