DUST PREVENTION AND ROAD PRESERVATION, 1916. 75 
These experiments have now been under way for about seven years, 
and the salient features of the records are summarized below for con- 
venience. 
The total length of the experimental road is 2,750 feet, and the 
width of the slag surface 14 feet. The blast-furnace slag was ob- 
tained from the Youngstown plant of the Carnegie Steel Co., and 
had weathered on the dump for some time. The slag was selected 
with care and was screened to the siz'es indicated for the different 
sections. The open-hearth slag was obtained from the ordinary basic 
open-hearth process and was ground to the size indicated. The tar 
was a refined coke-oven tar, and the waste sulphite liquor was a con- 
centrated form of the ordinary by-product in the manufacture of wood 
pulp. The traffic over the road is only moderate, but no actual counts 
have been taken. 
GARDEN CITY, DODGE CITY, BUCKLIN, AND FORD, KANSAS, 1908. 
SAND-CLAY. 
The original report of these experiments appeared in Circular 
No. 90, and reports of subsequent inspections in Circulars Nos. 92, 
94, 98, and 99, Office of Public Roads, and in Bulletins Nos. 105, 257, 
and 407, U. S. Department of Agriculture. 
Experiment at Garden Oity. — This road was inspected December 9, 
1916. The ruts and low places mentioned in the last report had been 
repaired by the addition of new material and by the liberal use of the 
road drag. The road had been resurfaced for a distance of 600 feet 
between station 6 and the bridge across the Arkansas River. There 
had been no rain since this work was done, and because of a lack of 
moisture the surface was not very well bonded. In general, this 
experiment was in a good condition. 
Experiments at BucMin. — This road was inspected December 8, 
1916. Its condition, in general, was very poor. The surface was 
badly rutted and had worn very thin in places. From station 46 to 
the bridge it had been badly damaged from flood water of the Arkan- 
sas River in the spring of 1915. This section had been rebuilt and 
surfaced and was in good condition except that the surface was very 
poorly bonded. The summer had been exceptionally dry and very 
little improvement had been made by using the road drag in main- 
tenance. 
Experiment at Ford. — This road was inspected December 8, 1916, 
and was in good condition generally. The low places and ruts men- 
tioned in the last report had been properly repaired. The surface 
was very smooth and well bonded. 
These experimental sand-clay roads have led, either directly or 
indirectly, to the construction of many similar roads in that part of 
the country. According to statistics gathered by the Office of Public 
