PARK AND CCMETE-RY 
440 
Mactiine Road MaKin^. 
The impassable condition of many of the public 
roads in different parts of the country has led to the 
conducting of extensive experiments in road making by 
the government with a view to developing some sys- 
tematic method of improvement. The work is carried 
on by the Office of Road Inquiry, a division of the De- 
partment of Agriculture, and is described as follows 
by Waldon Fawcett in the Scientific American, from 
which our illustration is taken : 
Probably the most interesting phase of the work has 
been found in the construction of specimen roads of 
various kinds in different parts of the country. Ordi- 
narily three styles of road have been represented in this 
experimental work — a modern macadam, a sand and a 
dust, is put in place for rolling and finishing. The 
sand road is formed by placing six inches of river 
sand on a bed of natural clay, neither the bed nor 
the surface of the road being rolled. The dirt road is 
made by grading in the usual manner. As a rule 
neither of these latter classes of highways is con- 
structed save to demonstrate the superiority of the mac- 
adam road. Considerable attention has been given to 
the construction of steel-track wagon roads — decidedly 
the most novel type of highway yet introduced in any 
country. The steel road might be compared to a street 
car track of modified design, and the plan for its util- 
ization was doubtless suggested by the well-known 
tendency of teamsters to make use of urban and inter- 
AN ELEVATING GRADER AT WORK. 
dirt road. Of these three the macadam highway is the 
most interesting from the point of construction. After 
a uniform grade has been secured by the use of wheeled 
scrapers, drag scrapers and plows, and possibly road 
graders as well, there are placed upon this foundation 
three separate layers of the best quality of stone that is 
procurable in the vicinity. The foundation course, 
which is about five inches in thickness and made up of 
two and one-half inch stone, is thoroughly rolled before 
the second course^ composed of one and one-half inch 
stone, is put on, and this layer in turn is sprinkled and 
rolled before the surface layer or “binder,” as it is com- 
monly called, consisting of three-quarter inch stone and 
urban trolley and cable lines on highways where loco- 
motion would otherwise be difficult. 
The extension of the good roads movement has re- 
sulted in a corresponding development of the engineer- 
ing operations involved and of the machinery err.- 
ployed. Possibly the most interesting of all the form.s 
of special apparatus which have been introduced for 
this work is the elevating grader which is utilized in 
reducing cuts several feet in depth. This machine ele- 
vates earth and drops it into wagons alongside, loading 
a wagon in twenty seconds. On an average such a 
machine will load into wagons in one day of ten work- 
ing hours from 700 to 800 yards of earth. 
