52 BULLETIN 462, U. S. DEPARTMENT OF AGRICULTURE. 



The first experiments by the writer in Florida were made in a 

 grove near Orlando, in 1909. The owner of the grove had set up a 

 25-horsepower engine and a pump which did not work satisfactorily. 

 He was advised to install a single-stage centrifugal pump, capable 

 of delivering about 700 gallons per minute to the highest part of the 

 grove, about 35 feet above the surface of the lake from which the 

 water supply was obtained. Two 5-inch wrought-steel mains carried 

 the water to the top of the grove, a distance of about 500 feet. 



The question now was how to distribute this water to the best 

 advantage from the end of the main without expending large sums 

 of money on iron or steel piping systems. Upon making a survey 

 of the 40-acre grove it was found that all of it could be covered by a 

 pipe system requiring heads of water not larger than 10 to 15 feet 

 after the water had been pumped through iron pipe to a high j)oint 

 in the grove. Concrete pipe has been found satisfactory in some 

 parts of Florida, but the poor grade of sand which had to be used 

 discouraged its general use there. The sand was procured from Lake 

 Weir and is considered good for ordinary concrete work, such as 

 building blocks ; but a sharp, clean sand should be selected for good 

 concrete pipe, such as is used for irrigation purposes in the "West. 

 The principal objection to this pipe was the difficulty, with the labor 

 available, of concreting the separate joints together so as to make 

 them watertight. This could be accomplished in several ways, but 

 would require special apparatus and considerable care. 



Terra-cotta sewer pipe was found to answer every requirement, 

 although care was necessary in laying it. (PL V, fig. 1.) The 

 remainder of the distributing system was, therefore, finished with 

 the terra-cotta pipe, which has given the best of satisfaction during 

 the last six years, and judging from its use throughout both East and 

 West it should continue satisfactory for an indefinite period. 



The outlets from the terra-cotta distributing system were made by 

 connecting special irrigation valves to short upright pieces of 6-inch 

 terra-cotta pipe, which were connected to the main pipe by the ordi- 

 nary terra-cotta T. Six, eight, and ten-inch pipes were used. 

 These were laid in trenches on the highest ridges throughout the 

 grove. The pipe was cemented together so as to make water-tight 

 joints, and was then covered with earth, the top of the pipe then be- 

 ing at least 12 inches beneath the surface. 



Probably the most important item in the construction in this grove 

 was the arrangement to prevent excessive pressure in the terra-cotta 

 pipe. If the iron main from the pump Avere connected directly to 

 the terra-cotta pipe it is probable that the pipe would burst from 

 water hammer, or sudden starting or stopping of the water. To pre- 

 vent any possibility of this a relief standpipe was constructed at the 



