THE FLOY/ OF WATER IN WOOD-STAVE PIPE. 81 
in all the waters tested, and the variation in specific gravity from that of distilled 
water was found to be very slight. As it was not practicable to make an examination 
of the interior of this pipe the nominal size was accepted as correct. It conveys water 
for several miles down the A T ery rugged canyon spoken of in the discussion of pipe No. 
31. Both vertical and horizontal curves are numerous but not excessively sharp. 
These tests excited much comment at the time for the reason that they were the first 
to show that a value of about 0.010 for n in the Kutter formula would not apply to all 
sizes of pipe under all velocities. When compared with all other tests on large pipe, 
with the exception of Nos. 45 and 4G, the capacity of this pipe is shown to be about 
equal to the discharge computed by formula. Compared to the new. formula the 
capacity is from 5 to 8 per cent less than average. For further discussion of results on 
this pipe see page 9. 
ADDITIONAL DATA. 1 
The following experiments have been made on wood-stave pipes 
since the original publication of this bulletin, in 1916, or, if made 
previous to that date, have more recently been called to the attention 
of the writer. The Campbell tests (Nos. 15 and 21), rejected in the 
original publication, have been made acceptable and are now given 
full weight. The essential data are given in Table 9 on page 86. 
No. 53. 4-inch Inserted Joint Fir Pipe. 2 Ranch of H. R. Wells, Yakima, 
Wash, — In 1908 T. A. Noble and C. W. Harris made a series of tests on a 
pumping line near Yakima, Wash. Of these tests they finally offered the results 
of two runs, one on a low-level reach of 717.7 feet and one on a high-level reach 
of 1,321.1 feet. The discharge was measured over a thin-lipped weir without 
end contractions, quantity being calculated by the Bazin formula, and after- 
wards checked by volumetric measurements. Mercury manometers of the pot- 
and-column type were used at the high-pressure ends of the reaches and water 
columns at the low-pressure ends. The age of this pipe and the method of 
making piezometer connections were not given. In this paper Mr. Noble senses 
our present understanding that the Kutter formula should not be used in de- 
termining the capacity of stave pipes. He writes: " There are sufficient (tests) 
to thoroughly demonstrate that the old method of calculating the flow by Kutter's 
formula is intrinsically wrong." 
No. 54. 8-inch Machine-Banded Untreated Douglas Fir Pipe. Water Supply 
for Marysville, Wash. 3 — Soon after the completion of the Marysville line in the 
fall of 1921, R. E. Koon measured the discharge and found 0.80 second-foot of 
water. As the total length of the line is 46,000 feet from springs through a 
settling basin to an elevated tank, and the total head consumed in friction loss 
is 137 feet, there are sufficient data for an acceptable test. The great length of 
the line removes the necessity for simultaneous readings of gauges attached to 
piezometer connections. The line may be considered as practically straight, as 
there are only two right-angled bends near the point where the water is discharged 
into an elevated tower and two similar bends about midway of the line. This 
observation checks our formula within less than 1 per cent. 
i In the first edition of this bulletin, published in 1916, there appeared an extended discussion by several 
engineers. This discussion pertained, for the most part, to the formula then ofTered for the first time. 
This formula has been very generally adopted by both manufacturers and engineers so that further de- 
fense does not appear necessary, and the discussion is omitted in order to make room for additional data. 
The reader who wishes to read the discussion is referred to the edition of 1916 which is on file in most public 
libraries. 
2 Wood Pipe, by Theron A. Noble, Pro. Pac. Northwest Soc. of Engrs., Vol. IX, No. 1 (1910), Seattle, 
Wash., p. 7. 
s Notes for this test submitted in correspondence by R. E. Koon, consulting engineer, Portland, Oreg. 
68796°— Bull. 376—25 6 
