178 CALIFORNIA FRUITS I HOW TO GROW THEM 



require the services of competent engineers. All these matters are too 

 great in extent and variety to be discussed in this work. As, however, 

 it has been the aim of the writer to aid the inexperienced planter to 

 help himself in small efforts, a little space will be given to suggestions 

 as to how a planter may develop and use such small water supply as 

 may be derived from spring, small creek or well, on his own land 

 without employing an engineer. 



Running Lines for Irrigating Ditches. How far to go up a 

 creek in order to bring water out upon a given piece of land is a ques- 

 tion which frequently arises in individual practice. There is also doubt 

 as to how much fall should be given to the ditch. The fall required 

 by a ditch or canal depends upon the amount of water which it is 

 desired that it shall discharge, and upon the width and depth with 

 which it is intended that the water should flow. It may also be 

 dependent upon the character of the soil in which the ditch is to be 

 constructed, and upon the peculiarities of the water itself. A strong 

 current in soft soil may cause mischievous erosions. Water carrying 

 much sediment must never be allowed to move sluggishly, as clear 

 water sometimes may. It is best to state the requirements to a compe- 

 tent engineer and act on his suggestion, or secure the counsel of a 

 neighbor who has had experience with similar soil and water. 



Having decided what fall to give the ditch, the nearest point of 

 which water can be taken out of the creek to be brought to a certain 

 piece of land is found by commencing with the point at which the 

 water is to be delivered (generally the highest point of the land to be 

 irrigated), and running up stream a line which has the inclination 

 intended for the ditch. 



To stake out this line when no special hindrances are in the way, 

 use a home-made leveling instrument constructed as follows: 



With sound, straight-edged lumber a triangle is made, as indicated in the 

 sketch. The three pieces, A B, 6 feet long, B C, 12 feet long, and C A, 4 feet 

 long, are made fast to each other at A B } and C. The board, A D, is fastened 

 to the triangle at right angles to B C. Near A } on the board, A D, a plumb-line 

 is made fast. The plumb, like a mason's plumb, hangs in a hole at 'F, so that 

 when A D is vertical, the string hangs very near the surface of the! board, A D. 



It will be seen that when A D is exactly vertical, B C is 'exactly horizontal, 

 if the angles at D are true right angles. An ordinary carpenter's square used in 

 the construction of the apparatus will insure sufficient accuracy in the position 

 of A D. 



In marking on the board, A D, however, the line in which the string of the 

 plumb will hang when B C is exactly horizontal, more care is required. Two 

 pegs are driven, as far apart as B and" C, for these points to rest on. The high- 

 est one 'is driven into the ground until the plumb-line follows about the center 

 line of the board, A D. Having marked this ^osition of the plumb-line, the 

 triangle is reversed so that the end B rests on the peg, where before we had the 

 end C, and vice versa. Should the plumb-line be in a position at variance with 

 the first one marked on the board, then the correct position for the B C horizon- 

 tal will be exactly in the middle between the two found by the aid of the two 

 pegs. 



It will frequently be found convenient to have a scale of feet marked off on 

 B C. Holes in the pieces A B and C A at E E, or handles, will make the triangle 

 convenient to carry. Only two men are necessary in using it. 



