The Detroit times. [volume] (Detroit, Mich.) 1903-1920, 1911-06-28
From the Department Of Public Works.

From the Department OF Public Works.
To the Honorable the Common Council:
Gtntlemen--In reference 10 the ques-
lions raised by the communications of
his honor. the Mayor. pertaining TO the
RATHER test for paving brick, 1 beg 10
state; II was the custom or the Old
Board or Public Works TO require con-
tractors for brick pavements TO furn-
ish their own brick and give the city
q guaranty for the maintenance of
brick pavements for a certain number
OF years. The guaranty was later abau-
doned because IL gave contractors an
excuse TO raise prices and the city was
unable for various reasons 10 enforce
the guaranty TO any great extent.
Moreland was the first TO conceive and
nut into effect. In a small way. the
plan OF the city buying the brick and
furnishing them tor the contractors. The
plan was adoped and extended by May.
bury to all the brick used by him but
no guaranty was required OF the manu-
facturer I'm Maybury's time. The plan
or the city buying all OF che brick and
paying only for the accepted, measur-
ed brick in the pavements with a three
year guaranty from the manufacturers
secured by a Ave per cent cash deposit
tr bank. originated with me, and at
lords the best safeguard that has yet
been devised to protect the city against
bad brick. The rattler test was used
in~ Detroit for nine years by the Old
Board of Public Works in the early
ed because the result shown by that
test were often directly opposed TO
the wearing test OF the brick In the
Tavements and because tests also vari-
ed greatly with the same makes OF
brick. This has been the experience
OF every city In the country which has
ever experimental with the RATHER test,
so that the rattler as a test for paving
brick has been discredited for years.
What benefit may be derived from the
new RATHER now In our yard Is prob
been tested by any city in the country
so as to ascertain what percentage or
abrasion good wearing brick should
stand under its test. The twenty per
some cities quoted by the Mayor refer
red to the cid style rattlcr. since this
new RATHER was only completed late
last fall. On this point. Prof orion,
the Mayors expert writes; 1T Is also
true that IL has not been definitely
shown by any scientific investigation
what degree OF excellence, as measur-
ed by the rattler test, Is necessary TO
Justify calling a paving brick, Good"
or just what degree OF inferiority In
the rattler test makes paving brick
UNIT for use I'm the street. Prof Or
ton further says: 1T has been shown.
In cases that have come under my
knowledge that bricks which would
not show what would generally be
called n good RATHER test. have given
excellent results when actually laid In
the street" And again, while this does
not prove the RATHER test worthless. IL
does tend TO prove that we do not yet
know where to draw the line between
III and unit brick as measured by the
rattler test" As to percentages OF
abrasion, Prof. orion writes: The per-
centages adopted in different cities
thus far are usually fixed by the City
Engineer, on the best knowledge and
evidence that he can secure, which evil
dence. however. does aot amount to an
authoritative demonstration" In an
other paragraph he says: The fixing
OF the limit (of percentage) Is local
matter and should be settled by zach
community in the light of It's cwn
COMPOUNDED. for what can an "authori-
tative demonstration" OF paving brick
mean, according TO Prof Orton's own
ACTUAL WEARING TEST LAID IN
THE PAvEMENTS7 And. why should
one community demand a different per-
centage on the same brick than anoth-
err community IL the best results are
desired7 What percentage shall be FIX
ed for Detroit-"ln the light OF her
problems" when. as Prof. Orion says
above: 1--WE do not yet know where 20
draw the line between At and unit
brick as measured by the RATHER testT'
The above statements OF Prof orion,
the Mayors own expert, hired by him
dumping ground for rotten brick be-
cause ! had failed to install the rattler
test. stand unqualified by any other
statements In his letter. and accepting
them as. true. ! would like TO ask the
members of your Honorable Body what
is likely TO be added to our present
knowledge Of paving brick this season
by the use OF this new rattler. do
not wish TO be understood as being OPP
poPed 10 the RATHER test or any other
kind of test for brick That Will give
reliable results No one Ia or can be
more anxious than l am or have Oeen
10 get the best brick and the best pave
ments OF all kinds that can De had for
Detroit's streets because i well realize
that the reputation OF the Department
is very true that at the pi ssent time
the pavement surfaces on some OF our
brick and cedar streets are rough and
uneven. and that some or these same
streets have been eliminated from my
estimates for re-surfactng by -FOUR
Honorable Body and the Estimators,
but these bad streets are but q small
total Of the 400 miles OF pavement In
the CITY OF Detroit And these defec-
tive streets will be quickly repaired
tions become available, or after July
l. The disintegration OF the Prick
pavements In spots. principally on re-
surfacing work. has been investlgated
by me from every possible angle IN
NV efforts to discover the cause. Some
times one third or one-half the surface
In a given block VIII be affected the
balance OF the pavement surface in
next block may not be affected AT all
Again. whole streets paved with the
same kind 81 brick. IN the same man
ner and under the same conditions VIII
be found without flaw. All kinds OF
EXPANSION devices have been expert
mented with as well AZ laying .he brick
at various angles across The street and
with varying depths OF cushion sand and
still the blotches appear Many OF the
old natural cement foundations have
been badly cut up I'm the past for con-
duits and connections Of different
kinds which unuuestionabiy accounts
for some OF this trouble. which does
not occur 10 any such extent on the
newly paved streets with Portland Ce-
men, Concrete foundations i am now
literally reinforcing these old founda-
tions with Portland Cement Concrete
ana trying IN other WAYS TO overc 1me
this difficulty. I have purposely re-
Trained from any reference 20 the per-
sonal illusions 10 my self In the com
nunications OF His Honor. II the
Mayor really cared 10 determine wheth-
er or not Detroit was dumping ground
for bad brick he would obtain samples
OF the same kinds OF brtcx delivered I'm
other cities and compare them with the
brick delivered In Detroit j have Wis.,
tied many other cities. examined their
brick and their pavements and watched
their work Any member " your Hon
orable Body can do the same ! know
they have no better brick or other ma
terial, their methods are no better, and
IN most cases not as goot as ours and
thev get no better general results In
--zatro thga opnmunfcstfou 20 YOUR