In the early 1880's a conscientious contractor named W. T. G. Snyder paved the block-long street on the four sides of the Bellefontaine, Ohio courthouse and it wasn't until 1960 that obsolescence and progress dictated covering the pavement with a topping that would cost less than the $8,000 necessary for restoring it. Inasmuch as the four-block stretch, designed in five by five-foot slabs, is reportedly the country's oldest concrete paving job one slab was left uncovered to commemorate such history. In 1951, the Portland Cement Association Laboratories obtained several of the slabs for study. The unreinforced slabs, six to seven inches in depth and without dowels or load transfer, had been placed on a macadam base, of which the thickness and degree of consolidation are no longer known. Although the concrete contained no purposely entrained air, there in no record of the scaling and surface deterioration usually found after exposure to severe winters such as those in the Midwest. The PCA laboratory studies showed that concrete in the slabs was placed in one and one-half to 2 inch layers instead of full depth. There were no apparent planes of weakness or separation between layers, however. The pavement, each block-long stretch of which was done in two consecutive strips full length, was cut full depth at five-foot intervals, with tar paper used to maintain separations. Slab edges were neatly finished and the surface was grooved at four-inch intervals to provide traction for horse's feet. Curing was done under two inches of wet sand for one week.
