SEWER DIAGRAMS 185 



edition, by Staley and Pierson, are made up from Latham's 

 tables, and the difference between these values and those 

 from Kutter's formula are well shown in the second and later 

 editions, where Kutter's lines are printed in red on the same 

 plate. 



Among the diagrams compiled by J. Leland FitzGerald, 

 reprinted on a plate in Baumeister's " Sewerage " (First 

 Edition), is one also based on Latham's tables, giving the 

 discharge of circular and egg-shaped sewers. (Engineering 

 News, Vol. XXIV, p. 212.) 



The first diagram based on Kutter's formula was 

 published in the Trans. Am. Soc. C. E., Vol. VIII, p. i, by 

 Rudolph Hering, and reprinted by the Society for general 

 use. It has discharges for ordinates, and slopes in feet per 

 hundred for abscissae. The intersecting curves are those for 

 velocities and diameters, and a separate sheet is required for 

 different values of n. One such sheet (# = .013) is given in 

 Engineering News, Vol. XXXII, p. 449. 



A diagram computed by Mr. Moore of St. Louis is given 

 in the Journal of the Association of Engineering Societies, 

 Vol. V, p. 360, whose ordinates are diameters, and abscissae 

 discharges in cubic feet per second. The intersecting curves 

 then are velocities and grades, given in fall per hundred feet. 

 This is not as well adapted for use as the first, both in that 

 the intersections are more oblique and that in order to read 

 for small pipe a supplemental diagram of the corner has to be 

 redrawn on a larger scale. 



In the Engineering News for August n, 1892 (Vol. XXVIII, 

 p. 127), is a carefully drawn diagram by Professor Talbot of 

 the University of Illinois. Here the discharges were made 

 ordinates, and the gradients in per cent the abscissae. The 

 square roots of the gradients were plotted instead of the 

 gradients themselves, and in order to get better intersections 

 the axes of the diagram are inclined towards each other. The 

 line of equal diameters becomes a straight line, and in order 

 to get the 6- and 8-inch pipes on the diagram their discharges 



