552 
BITUMINOUS PAVEMENTS CONSTRUCTED BY 
MIXING METHODS 
Fluxed Native As- 
phalts Oil Asphalts 
Tars and Tar- and Residual As- 
Asphalt Com- phaltic and Semi- 
pounds asphaltic Oils Light Oils 
1908.. 52,100 1908.. 4,400 MQW. 00660 
1909. .136,000 1909. .219,500 IMO) sosscs 
1910. .158,000 1910. .432,600 UDMNOss00006 
1911.. 24,350 1911. .508,100 NOIRE Matas 
The most important developments during 1911 
were as follows: the increased use of the mixing 
method of constructing bituminous concrete pave- 
ments due to the introduction of economical and 
efficient mixing plants and less fear of injunction 
and law suits brought by patentees; the manu- 
facture of many types of gravity and pressure 
distributors for use in the construction and main- 
tenance of bituminous surfaces and bituminous 
pavements built by penetration methods; the de- 
mand by many engineers for bituminous materials 
for bituminous surfaces which will set up in from 
24 to 48 hours; increase in recording scientific 
data such as recommended by the special com- 
mittee on the Use of Bituminous Materials of the 
American Society of Civil Engineers. 
Organization of a Highways Maintenance Bureau 
of a Municipality: W. H. CoNNELL, New York 
City. 
It is, in the writer’s opinion, desirable in the 
organization of a Highways-Maintenance Bureau 
to follow the theory of centralization of control. 
First comes the planning of an organization 
adapted to the needs of the municipality, then the 
proper control of the same, which can only be ac- 
complished through the appointment of men espe- 
cially qualified to supervise the work of the various 
branches of the organization. The responsibility 
of course should be centered in one man, and he 
should be familiar with the social conditions of 
the municipality and keep in close touch with the 
activities of the divisions under his control. All 
work should be initiated through job orders and 
unit cost records kept of the same. All street 
repairs, ete., should be done by the highways- 
maintenance force. All repairs to pavements be- 
tween railway tracks over corporation cuts, etc., 
should be done through and under the supervision 
of the Highways-Maintenance Bureau. This pro- 
cedure centralizes the responsibility and control of 
work coming under the jurisdiction of said bureau. 
SCIENCE 
[N.S. Vou. XXXV. No. 901 
Utilization of Motor Truck Trains in the Main- 
tenance of Truck Highways: L. W. Paces, Office 
of Publie Roads. 
The object to be accomplished is the develop- 
ment of an automobile equipment which will in- 
elude all the apparatus and facilities necessary to 
efficiently employ a repair gang of eight men in 
the maintenance of road surface over one hundred 
miles of roadway or more as the working condi- 
tions will permit. This purpose as set forth has 
three significant implications: First, that the cost 
of the equipment should be kept consistently low 
or within the range of customary expenditures in 
this direction; second, novel or especially manu- 
factured apparatus should be avoided so that the 
equivalent apparatus can be secured in any locality, 
and, further, that existing investment in similar 
details of equipment can be made use of; third, 
that the outfit should be so flexible in its makeup 
as to readily serve a variety of utility or lend itself 
to peculiar requirements under varying conditions. 
In performing service in road repairing, the ma- 
chine should incorporate as many of the require- 
ments of a portable power plant as possible, such 
as hoisting, pumping, and, where necessary, air 
compression and power-shaft driving. The auto- 
mobile chassis selected for recommendation is the 
5-ton gas-electric type manufactured by the 
Couple-Gear Freight Wheel Company, Grand 
Rapids, Michigan. This chassis is fitted with a 
Sprague electric hoist, which can be used for a 
variety of purposes. The motor of this hoist is 
directly connected to a rotary pump which can 
be used to furnish bituminous material from a 
tank carried on the machine through a distributing 
device permanently attached to the rear of the 
chassis. An electric air compressor and a power 
sweeper could also be attached to the machine. 
The chassis can be fitted with a removable plat- 
form body, with or without stakes or side racks; 
and it may also be fitted with a steel dumping 
body, the forward half of this body to be fitted 
with removable partitions to provide spaces of one 
or two cubic yards capacity for carrying different 
sizes of road material. The rear half of the body 
may be used for carrying the bituminous heating 
tank. Seats for four men and spaces for tools are 
provided between the dumping body and the 
driver’s seat. The latter is made wide enough to 
earry three men beside the driver. It would be 
impossible to use standard wagons as trailers for 
carrying material, and a sprinkling wagon or 
bituminous tank mounted on its own wheels could 
also be carried behind the tractor. It would prob- 
