SPRAY IRRIGATION. Bul 
drilling for the nozzles. Where pipe posts are used, the pipe can be 
held in place for drilling by wrapping a tight wire twice around-the 
posts, then looping the wire around the nozzle pipe line so that the 
pipe will hang several inches below where it is attached to posts. 
The pipe is then fastened rigidly so that it can not turn while being 
drilled. A good way to do this is to replace the handle in the turn- 
ing union with a 10 or 12 foot length of #-inch pipe, so that one end 
will rest on the ground, acting as a wrench holding the entire line. 
The nozzle holes are then spaced with a stick cut the proper length 
and marked with crayon. Three to four feet is the usual distance 
between the nozzles. 
The nozzle holes must be in a straight line along the shell of the 
pipe. To accomplish this a special drilling machine is used. This 
machine hangs on the pipe and ‘can be set in a perpendicular position 
by means of an attached level bubble. It is securely clamped for 
each drilling and the hole is made on the lower side of the pipe. The 
shank of the drill is a thread tap, so that the hole is threaded by run- 
ning the drill into the pipe at the completion of the hole. Lard oil 
only should be used on the drill, as mineral oils cause the metals to 
heat and pinch the drill. A drop or two of oil placed on the upper 
side of the pipe will run to the lower side and be sufficient for each 
hole. 
When the drilling of a line is complete the pipe is placed in its 
permanent supports and connected to the feed pipe. It always is 
desirable to run. the water through the lines before screwing in the 
nozzles. This will wash out all the foreign materials in the pipe, 
and the nozzles can be put in at any time. When the water is first 
pumped through after the nozzles are in place, the end of the pipe 
should be left open for a time and each nozzle inspected. Scales or 
dirt in a nozzle can be dislodged by striking the opposite side of the 
pipe a sharp blow with a hammer while a finger is placed over the 
| nozzle. A small wire thrust into the nozzle and quickly withdrawn 

also assists in removing obstructions. 
COST DATA. 
Cost data for material can be given only for general estimating 
purposes, as the markets fluctuate and the prices must vary also 
with the freight to different points. 
Manufacturers have a standard list of prices on pipe and fittings 
from which discounts are given, according to the condition of the 
metal market, freight rates, and size of order. The standard lists 
are given in Table 7, with the probable range of discounts based on 
Pittsburgh, Pa. 

