Graceful and natural curves conforming to the lay of the land add beauty to the landscape, besides enhancing the value of property. Not only do level, curved roads add beauty to the landscape and make lands along them more valuable, but the horse is able to utilize his full strength over them; furthermore, a horse can pull only four-fifths as much on a grade of two feet in one hundred feet, and this gradually lessens until with a grade of ten feet in one hundred feet he can draw but one-fourth as much as he can on a level road. All roads should therefore wind around hills or be cut through instead of running over them, and in many cases the former can be done without greatly increasing the distance. To illustrate, if an apple or pear be cut in half and one of the halves placed on a flat surface, it will be seen that the horizontal distance around from stem to blossom is no greater than the distance over between the same points. The wilfulness of one or two private individuals sometimes becomes a barrier to traffic and commerce. The great drawback to the laying out of roads on the principle referred to is that of the necessity, in some cases, of building them through the best lands, the choicest pastures and orchards, instead, as they do now, of cutting around the farm line or passing through old worn-out fields or over rocky knolls. But if farmers wish people to know that they have good farms, good cattle, sheep, or horses, good grain, fruit, or vegetables, they should let the roads go through the best parts of the farms. The difference in length between a straight road and one which is slightly curved is less than one would imagine. Says Sganzin: "If a road between two places ten miles apart were made to curve so that the eye could see no farther than a quarter of a mile of it at once, its length would exceed that of a perfectly straight road between the same points by only about one hundred and fifty yards." Even if the distance around a hill be much greater, it is often more economical to construct it that way than to go over and necessitate the expenditure of large amounts of money in reducing the grade, or a waste of much valuable time and energy in transporting goods that way. Gillespie says "that, as a general rule, the horizontal length of a road may be advantageously increased to avoid an ascent by at least twenty times the perpendicular height which is thus to be avoided--that is, to escape a hill one hundred feet high it would be proper for the road to make such a circuit as would increase its length two thousand feet." The mathematical axiom that "a straight line is the shortest distance between two points" is not, therefore, the best rule to follow in laying out a road; better is the proverb that "the longest way round is the shortest way home." The grade is the most important factor to be considered in the location of roads. The smoother the road surface, the less the grade should be.