PARK AND 
CEMETERY. 
133 
TRENCH CUT IN EAST DRIVE, CENTRAL PARK, SHOW- TRENCH SHOWN IN ACCOMPANYING ILLUSTRATION, 
ING 24 INCHES OF GRAVEL ON FOUNDATION. SHOWING BURIED EDGING STONE BELOW 
PRESENT GUTTER. 
spread a coating or wearing course of ma- 
terial such as is herinafter specified, of such 
depth that after being thoroughly rolled and 
compacted, it shall have a thickness of not 
less than 2 ins. over the entire area of the 
roadway. The rolling and compacting shall 
be done to the satisfaction of the engineer 
with a roller weighing from 8 to 10 tons 
and of such construction as will force the 
material of the wearing surface into any 
voids which may be left in the concrete foun- 
dation. 
Composition of Wearing Surface. — The 
wearing surface shall be composed of not 
less than 6 per cent of asphalt cement and 
not less than 10 per cent of powdered nat- 
ural bituminous rock. The balance shall 
be made up of fine, clean sand. This compo- 
sition must be entirely free from coal tar or 
coal tar products and shall be made into a 
soft, tough mixture, which shall not liquefy 
or become sticky in hot weather. 
Asphalt Cement. — The asphalt cement 
shall be homogeneous and practically free 
from water and vegetable or mineral mat- 
ter, and shall have a specific gravity of not 
less than 1.03 and shall contain not less than 
98 per cent of bitumen soluble in carbon 
bisulphide; of this contained bitumen soluble 
in carbon bisulphide, 98 % per cent shall be 
soluble in carbon tetrachloride. When 20 
grams are heated at a temperature of 325 
degrees F. for 7 hours, in a tin box 2V6 ins. 
in diameter, there shall not be a loss of 
weight in excess of 3 per cent. The bitumen 
at 77 degree F. shall have a ductility of not 
less than 90 cm. when tested by the District 
of Columbia method and shall possess a pen- 
etration of between 200 and 240. 
Bituminous Rock. — The bituminous rock 
used shall be either a natural bituminous 
limestone rock (1) from the French mines 
of Seyssel or Mons, equal in quality and 
composition to that mined by the Compagnie 
Generale des Asphalte de France (2) from 
the Swiss mines at Val de Travers, equal in 
quality and composition to that mined by 
the Neuchatel Asphalt Company, Ltd., (3) 
from the Sicilian mines at Ragusa and the 
German mines at Limmer, equal in quality 
and composition to that mined by the United 
Limmer and Vorwohle Rock Asphalte Com- 
pany, Ltd., or (4) any natural bituminous 
limestone or sandstone from any mine which, 
in the opinion of the Commissioner, produces 
a bituminous rock equally as good for the 
purposes required; in any event, the rock 
asphalt shall contain 10 per cent of bitumen 
soluble in carbon bisulphide. 
Delivering and Laying of Mixture. — The 
above described materials shall be mixed in 
the determined proportions in a standard 
asphalt mixer and the mixture shall be heat- 
ed sufficiently to permit of its being properly 
spread on the roadway. It shall be brought 
on the work in wagons and shall be dumped 
on the concrete foundation and shoveled in 
place and raked to secure the proper grade. 
As soon as the temperature will permit, the 
paving mixture shall be rolled in a manner 
described in paragraph 41 [First paragraph 
of specifications quoted here. — Ed.], the roll- 
ing to continue until the surface gives indi- 
cation of no further compressibility. Along 
the gutters, which are of asphalt, the com- 
pression shall be secured by the use of iron 
tampers. The mixture must not be incorpo- 
rated with other material to increase its 
bulk, but shall be laid in the condition as 
delivered on the work, except for such man- 
ipulation as shall be required to properly 
apply it to the roadway in order to produce 
satisfactory results. The completed pavement 
shall have the thickness specified above with 
its surface even and true to grade. 
Samples. — The bidder must deposit with 
the Commissioner at least twenty-four hours 
before the time set for the opening of the 
bids, samples of materials he proposes to 
use in the construction of the bituminous 
wearing surface and a statement showing the 
locality of the mine from which the bitumi- 
nous rock was obtained. At any time dur- 
ing the continuance of this contract, the 
Contractor shall furnish to the Commissioner 
upon demand and without cost to the City 
further samples of materials which he is 
actually using in the construction of the 
wearing surface. 
Price. — The price bid for the new roadway 
surface must be a price per square yard, 
covering the full expense of furnishing, de- 
positing and rolling the bituminous wearing 
surface as herein specified and must include 
the cost of maintaining both foundation and 
wearing surface in good condition for the 
period of 5 years. 
The estimated cost of this work is 
about $100,000, and an appropriation 
of $300,000 has been asked for other 
work of the same nature in Central 
Park and on Riverside Drive. It is 
Commissioner Stover’s expectation 
that a considerable saving will be ef- 
fected in this work by using the grav- 
el excavated from the driveways for 
making the concrete for the new foun- 
dations. This, Commissioner Stover 
states, will necessitate the installation 
of machinery for washing and screen- 
ing the gravel and will make neces- 
sary a determination of whether or 
not the bituminous materials which 
have been used have affected the 
gravel in such a way as to injure it 
for use as aggregate in the concrete. 
One estimate places the probable sav- 
ing at 75 cts. per cu. yd. 
Besides the work on the drives in 
the park, it is planned to resurface 
three of the four transverse roads. In 
addition to the $100,000 available for 
the work on West Drive, the depart- 
ment has available funds amounting 
to $75,000 to be applied to the work 
on the transverse roads, and the prob- 
lem confronting the officials is the 
construction of these three roads at 
a cost not exceeding $25,000 each. 
The present plan is to lay a 7-in. con- 
crete foundation on each, at a depth 
of 6 ins. below the top of the reset 
curbs. On this will be put a flush 
coat of bituminous material, spread 
with gravel or trap rock, and this 
pavement used until such time as 
funds are available for the construc- 
tion of a wearing course of about 2 
ins. of some approved pavement. 
PROTECTION OF OUR BIRDS 
While the protection of our birds 
from ruthless destruction should be 
cared for by every state legislature, it 
should be done under carefully con- 
sidered law, or the official selected to 
carry out protective laws should be a 
man of broad common sense. We have 
recently noticed a newspaper account 
which recorded that the birds in a cer- 
tain locality had become an intolerable 
nuisance, owing to their rapid increase 
under protection. As nature goes she 
provides for such emergencies, and has 
her own particular methods, albeit ap- 
parently cruel in many respects. In 
our own legislation on so delicate, yet 
important a subject, ample discretion 
should be given to a competent warden 
to maintain balanced conditions. 
