380 



EXPEEIMENT STATION RECORD. 



tion of immune sera, nor do leucocytes seem to take a part in tlie process 

 except fliiit they may inliibit ttie multiplication of tlie bacteria. 



Sulphocarbolates in the treatment of white diarrhea (bacillary form) of 

 young chicks, G. D. IIoeton (Amer. Vet. Rev., 46 (lOUf), No. 3, pp. 321, 322).— 

 In oxperiuionts conducted by the author at the Oregon Agricultural College in 

 which a total of 50 chicks received the sulphocarbolate treatment, as rec- 

 onmiended by Kaupp in the work previously noted (E. S. R., 31, p. 88), only 

 seven of those thus treated remained alive at the end of ten weeks. " From the 

 manner in which the chicks died off and from the general appearance of the 

 seven that remained alive it seems evident that sulphocarbolates in the treat- 

 ment of white diarrhea (bacillary form) have A'ery little, if any, efficiency." 



Diseases transmitted by ticks; their classification, treatment, and eradi- 

 cation, A. Theiler, C. E. Gray, and W. M. Power {Amer. Vet. Rev., Jf6 {1914), 

 No. 3, pp. 281-297). — This review of the subject was presented at the Tenth 

 International Veterinary Congress, held at London in 1914. 



RURAL ENGINEERING. 



Concrete lining as applied to irrigation canals, S. Fortiee {U. >Sf. Dept. 

 Agr. Bui. 126 {1914), pp. 86, pis. 11, figs. i5).— This publication treats of the 

 subject of concrete lining for irrigation canals from the standpoint of economy, 

 design, and construction and is intended for the use of irrigation engineers and 

 the managers and superintendents of irrigation systems. 



The results of 321 sets of measurements of seepage made on different canals 

 are summarized in the following table : 



Summary of seepage measurements expressed in terms of percentage of total 

 flow lost per mile of channel for various sized canals. 



It Is concluded from these results that seepage is the most important source 

 of loss from canals. 



From the results of 76 measurements of flow of 18 canals it is concluded that 

 the so-called coefficient of friction n is on an average larger than has usually 

 been assumed by engineers. " The results show that only in rare cases, where 

 conditions are more or less ideal, is one justified in assuming a value as low as 

 0.012 for »." 



The following values for n are given to serve as a guide in estimating the dis- 

 charge of lined canals: (1) n = 0.012 for concrete-lined canals having a smooth 

 sidewalk finish, clean bottom, no moss, uniform cross section, well-formed joints, 

 long tangents, flat spiral curves, no perceptible undulations on the surface of 

 the water, and in general the best construction and the best conditions obtain- 

 able in practice. (2) n = 0.013 for concrete-lined canals having conditions 

 slightly better than those of type 3 and not so good as those of type 1. (3) 

 71 = 0.014 for concrete-lined canals having an unplastered or rough troweled sur- 

 face, clean bottom, uniform cross section, well-formed joints, medium curvature, 



