492 KANSAS CITY REVIEW OE SCIENCE. 



nearly all the heavy loads are confined to the ten and one-half foot strip of pav- 

 ing between the railroad track and the curb, show a wear of about three-eights 

 of an inch in nearly two years. 



There has been no repairing done on these streets, and there is no indica- 

 tion that any will be for some time. At all places where the pavement has been 

 broken into, the concrete is found to be hard and compact. In one instance it 

 was carrying the traffic of the street over a hole four feet across underneath. 

 The bituminous concrete between the blocks has always appeared well formed, 

 with but few voids occasionally near the bottom. The blocks are so thoroughly 

 fastened together that sections of four to six square feet have been taken up with- 

 out breaking. No swelling of the blocks and raising from the concrete has been 

 observed. In very cold dry weather fine cracks appear running nearly directly 

 across the surface of the pavement. They usually occur on steep grades and open 

 from one to one and one-half inches if the extreme low temperature continues, 

 but close up again with warmer weather. 



The first stone pavement laid after the Medina stone, on a part of Fifth 

 Street, was on a part of Bluff Street. Owing to the exceptional location of this 

 street, no petition from adjoining property-owners could be expected, and in 

 view of the public importance of this thoroughfare an appropriation of $15,000 

 was made out of the general fund to pave it. It was expected that a sufficient 

 thickness of the old MacAdam metal would be found to form a good foundation 

 on most of this street, considering the tons of broken stone that had been hauled 

 there during the previous years. In the absence of this the specifications called 

 for a six inch concrete foundation, which, in fact, was found necessary over the 

 whole street. On this was placed a layer of two to four inches of sand. Rectan- 

 gular block-s of the Argentine, or other good quality of native stone, was used for 

 the wearing surface on my recommendation. The work could not be put under 

 contract until late in the season, and consequently the eastern half, below Sixth 

 Street, was prosecuted during the worst kind of winter weather — with the sub- 

 grade constantly wet from side-hill drainage, rains and snow, and was dug up to 

 considerable extent by the gas company. 



New quarries were opened and much of the stone laid in frosty condition on 

 frozen sand; only the most urgent public necessity could justify doing the work 

 under these circumstances. The western half remained unpaved and in nearly 

 impassable condition, until early in the following spring. Meanwhile the large 

 volume of the heaviest traffic in the city was turned on to the new pavement. 

 This pavement cost $2.95 per square yard, or about $2.35 exclusive of the con- 

 crete base. 



A line of three-inch agricultural tile drain pipe was laid along each side of 

 the street near the gutters — that on the east side being for the purpose of drain- 

 ing the wet soil at the base of the hill, along which it runs — and that on the west 

 side for sub drainage and protection of retaining-wall. 



Observations of the wear of this paving show numerous minor depres- 

 sions of the surface, principally along the east side, and are due partly to unequal 



