44 BULLETIN 586, U. S. DEPARTMENT OF AGRICULTURE. 
OCALA, FLA., 1915. 
OIL-LIMESTONE, SAND-ASPHALT. 
The original report of these experiments was published in Bulletin 
No. 407. U. S. Department of Agriculture. The following report is 
based upon an inspection made December 16, 1916, when, judging 
from the general condition of the road surface and shoulders, it was 
apparent that the experimental sections had received no maintenance 
since their construction. ; 
Experiment No. 1—Limestone, residual asphaltic petroleum; pene- 
tration method.—The surface of this experiment appeared somewhat 
rougher than a year before, as the defects in construction showed 
more prominently owing to continued wear. At the same time this 
experiment demonstrates that with suitable care in construction a ~ 
very satisfactory road can be built by the penetration method, 
using the soft Ocala limestone. At the time of inspection the section 
showed some areas which had pitted, owing to the excessive wear 
on large exposed fragments of stone or to picking out of individual 
pieces. In a few other places there had been apparently faulty 
distribution, owing in some instances to the wearing course having 
been bonded too tightly before the bituminous material was applied. 
Traffic is concentrated on a 9-foot strip and the wear has been quite 
uniform in-the wheel tracks. Outside of the traveled way there was 
little evidence of wear. A seal coat over the entire section probably 
would prove of material benefit to the surface. 
Experiment No. 2—Sand-oil asphalt——This experiment was in 
practically the same condition as when completed in the summer of 
1915. At the time of inspection there were some slight waves or 
depressions which appeared to have deepened little since construc- 
tion, but at a few of the joints in the work slight depressions had 
formed. In a few places at the sides of the road, where there is no 
traffic, very slight cracks were apparent, but no cracks were eyi- 
dent where traffic exerts its action. In some places the limestone 
shoulders had worn considerably and needed immediate attention. 
So far as could be observed, the varying character of the base had 
caused no differences in the appearance of the surface and, as a 
whole the sand-asphalt experiment was in excellent condition. 
LEMON CITY, FLA., 1914. 
OILS, TAR PREPARATION, CALCIUM CHLORIDE-CORALLINE ROCK. 
The original report of these experiments appeared in Bulletin 
No. 257, U. S. Department of Agriculture, and a subsequent report 
of an inspection in Bulletin No. 407, U. S. Department of Agricul- 
ture. The following report is based on an inspection made Decem- 
ber 22, 1916: 
