width and depth to which the material is to be spread on, and the method of construction. All these things vary so much in the different states that it is impossible to name the exact amount for which a mile of a certain kind of road can be built.
The introduction in recent years of improved road-building machinery has enabled the authorities in some of the states to build improved stone and gravel roads quite cheaply. First-class single-track stone roads, nine feet wide, have been built near Canandaigua, New York, for $900 to $1,000 per mile. Many excellent gravel roads have been built in New Jersey for $1,000 to $1,300 per mile. The material of which they were constructed was placed on in two layers, each being raked and thoroughly rolled, and the whole mass consolidated to a thickness of eight inches. In the same state macadam roads have been built for $2,000 to $5,000 per mile, varying in width from nine to twenty feet and in thickness of material from four to twelve inches. Telford roads fourteen feet wide and ten to twelve inches thick have been built in New Jersey for $4,000 to $6,000
