136 LANDSCAPE-GARDENING 



Complete directions for the construction of drives 

 are not included in this book, since these are easily 

 found in treatises on engineering or government 

 bulletins. It is the desire here to emphasize the 

 importance of their location for convenience, com- 

 fort, and good appearance. The laying out of a 

 walk or drive on any desired grade is, however, so 

 simple and generally useful that every one who has a 

 farm or a large "place" in city or country should 

 know how to do it. A . hand level costing about 

 six dollars is the only instrument required. With 

 this, by merely sighting through, one can look in 

 any direction and determine a horizontal line ex- 

 tending from the eye. To illustrate how a line 

 on any desired grade is located, suppose the 

 observer's eye, when he is standing, to be five feet 

 from the ground, and the desired grade five per 

 cent. Stand at a low point on the proposed line. 

 With the level select a point that is of the same 

 height as the eye on the higher ground ahead and 

 about one hundred feet away. Have an assistant 

 pace one hundred feet toward this point and then 

 direct him to move to the right or left until the 

 spot upon which he stands is just on a level with 

 the cross wire of the instrument. He will mark 



