Telegram-herald., 1891-09-13

In . Comparative rs<s 10 Asssres Lee
nsissars asa Sassssussssy ~ Lee
AAsessa - Ersss thAa the Per-
ter ex Axs aan SpSetnsns

- - 0nD8r0Qye 10& ~ A~4Se A~
neisssrs Asa Sssssssssssy - Lee
Aasessa - Ersss thaa the Per-
ter ~ Hss asa spsstnsns-
Surveyor A. K. Calhoun, who prob
ably possesses IS complete q knowledge
of the practical sloe Of road cons,rao-
ton as any one IN Aofristown. Pa, has
been deeply interested observer OF the
discussion Of the kind Of material 70 Dc
used on Main-st.
In consequences of this interest he has
made q comparative analysis OF the
three kinds OF brick that have been un-
der discussion. namely, the Haliwood,
Porter and Hayden bricks. Whiie the
latter was nor subjected to any snniy SIS.
it Was already declared 10 be inferior 10
the Porter brick. The examination OF
their relative qualities wAs therefore
confined TO the Porter and Haslwood
specimens, which were subJecte1 10 .
critical test from . glanite basis. A
previous test of the Porter aud Hayden
brick had been upon q bass OF the Me-
dina stone, which is Of sand conforma-
ton and much softer In its composition
than granite. The tcst. which occupied
moro than . week ~ complete, - set
forth by Mr.. Calhoun a. follows:
II found the Haliwood brick possess
ing the higher modulus ct rupture and
decidedly the tougher Of the two, in
fact, comparing III this respect 70 gram
ite. found the specific gravity OF the
Hallwood brick to be $50, while that Of
the Porter was 2:i2. l found the Hall
wood erick 10 absorb the least water,
and therefore less liable to be affected
by frost. showing but o.59 per cent,
while that OF the Porter was 2:i.; the
average OF granite being about Oh. In
testing for the abrasion, or wear, the
most important OF all tesls, the infer
lority aud untitncss of the Porter brick
as y paving material was decidedly
shown, for with q similar kind OF pres
ssr applied for the samo length of time
on each, abrasion OF il was at leas. ~
times as much as the Hall sood."
This tost was suggested FROM tue fac,
that Hayden brick had been placed IA
the middle of the pave section Of stree,
at tho junction of Main and Dekalb-sts.
1t has shown very little wear during the
two years 1t has been there. and was
looked upon favorable by some of the
members Of the special committee oi
council.
A test OF paving brick was made at
the request of the board by City
Engineer Roberts at. Wicke's foundry
and the +. Il p. 81. machine shops by
placing half brick edgewise under a.
hydraulic press. The brick which was
accepted stood \ test of twenty tons
pressure on q surface OF about ten
squares inches. This brick was made
by the Ohio Paving company, which
was adopted by the board.
Similar pieccstof other brick we're
tested in the same manner, they stand
ing test OF twenty-threo to twenty
eight tons pressure on . similar sur
face. Another test was made by taking
sample of each brick and placing it
in q cylinder with about 100 ponnds of
scrap iron and rolling it for fifteen
hours to see what wear 1t would stand.
The Ohio compauy'a brick stood this
severe ordeal satisfactorily losing only
about TWO ounces while the others
were reduced to about one half their
original size.
The test were sufficient to establish
clearly that tho brick the hoard
accepted were superior in every re.
spect to any of the other samples sub
mitted. The samples that were tested
and the pieces that were rolled are on
exhibition at the Office Of tho city
engineer and open to public inspection.