The Helena independent. [volume] (Helena, Mont.) 1875-1943, 1891-06-04

nue., Now York. II consists OF n six-ineh
concrete foundation and then q, very little
sand. Upon this are placed carefully cut
granite blocks act on edge across the
streets, the joints carefully Tapped or bro
ken.'' Tho spaces between the blocks are
filled with hot gravel and pitch.
The best paving blocks are true granite.
Good sample specifications for standard
p~averuents of all kinds can generally be OBJ
tanned from all large cities.
Get good specifications written out in full.
Have all pavements guaranteed for a term
of years under bond, or the retention OF
from five TO 10 per cent of the cost, until
the end of the guaranteed period. This is
now done in European and many American
cities. Their see that tho specifications are
lived up to by the city and contractors
Property owners should attend to paving
done in front of their property rs we'll as to
building done upon 1t. They pay for both.
Engineering is often a knowledge of ma
terials and methods combined with common
sense. The specifications for pavements
describe the materials and their use. The
average American citizen can add the re-
Quirel common sense.
lie u6albn OF q Clpy NSPoAAa aAASS 70
much upon clean streets as upon an efficient
sewerage system. Professor Tyndall shows
that the mud Of our streets is composed al
most entirely OF vegetable and animal COM
pounds. taUe,
An impermeable pavement is the only
true sanitary pavement. This can be made
of cement. concrete or a bituminous foun-
dation can be laid. This is one OF the new
est and most successful foundations for
pavements. Upon the foundation of cement
or bituminous concrete a thin layer OF sand
is next placed, if we are to have a wearing
surface of stone blocks. Between the
blocks hot clean gravel and paving pitch
prevent the absorption of nexious COM
pounds. Every few years the joints should
be cleaned out and new pitch poured IN.
This is the c~ostliest but most durable OF
all stone pavements, however, 1T ID the best
adapted to streets for the heaviest trucking
in the largest business cities.
If the wearing surface is to be asphalt. 1t
is laid directly upon the solid foundation
and compressed. These two wearing sur
faces, stone blocks and sheet asphalt, are
the standard pavements OF all the great
cities of the civilized world.
All forms of block pavement, If placed
upon earth, sand or gravel, no matter how
we'll swept, always retain some filth. Every
rain increases the Objectionable percolation.
This is impossible with an imperviable
pavement; a rain not only cleans off the
street. but also quickly washes out the sew
ers. Recent microscopic examinations by
Prof. Ward, of Troy, tell US that the dust
of our houses is the dust of the street. 1t
is the carrier of many diseases, miti2ated,
however, by our fortunate frosts. We dread
getting street mud on our clothing. But
we breathe it's emanations in wet weather,
while in dry weather we breathe, as a dust,
the very stuff itself. We have it on our
bodies. We have it in our houses, where it
penetrates to every nook and corner.
Avoid the dust retaining and dust pro-
ducing pavement. 1t is a tax upon health.
Fortunately, also, the dust producing pave
ment in form of macadam is the most ex-
pensive street surface which can be at
tempted. The constant renewals and the
abundant and excessive sprinkling soon tax
some ones purse beyond all endurance.
The nervous strain under which we work
also demands that where possible noise be
suppressed.
The increase of good stone and asphalt
pavements, each kind in its proper place,
while promoting general efficiency and
eventual economy, makes city life more
healthful, relieves body and BRAIN.
In our local news columns we give also
some valuable suggestions regarding
material from DR.. G. @. Swallow.