1917] ETJBAL ENGINEERING. 681 



(1916), No. 2, pp. lSS-186). — This is a review of the literature relating to the 

 effect of cold upon trichinae, including the work of Ransoro. previously noted 

 (B. S. R., 34, p. 680). 



The occurrence of the ^ant nematode on the liver of a dog, W. A. Riley 

 and W. L. Chandler (ComeU Vet., 6 {1916), No. 4, pp. 209-212, pis. 2).— The 

 authors record a case of parasitism of the liver of a South Carolina dog by 

 Dioctophyme renale, together with the pathological conditions which it induced. 



Botulism, a cause of limber-neck in chickens, E. C. Dickson {Jour. Amer. 

 Vet. Med. Assoc, 50 {1911), No. 5, pp. 612, 613). — Investigations of outbreaks 

 of botulism due to the consumption of home-canned com, string beans, apricots, 

 etc., which resulted in the death of human beings as well as of chickens fed on 

 remnants of the materials indicate that botulism may be a cause of limber-neck 

 in chickens. Anaerobic bacilli, which had all the morphological and cultural 

 characteristics of Bacillus botuUntis, were obtained from the gizzards of several 

 of the fowls. The fact that the B. botulinus toxin may be formed in certain 

 vegetables and fruits without the addition of animal protein may explain the 

 occurrence of this disease of domestic fowl under conditions in which access to 

 spoiled meats can be excluded. 



RTTRAL ENGINEERING. 



The effect of sudden enlargement upon the flow of water in pipes, T. J. 

 RoDHOusE {Cornell Civ. Engin., 25 {1916), No. 2, pp. 49-61. figs. 3). — Experi- 

 ments on the effect of the flow of water of sudden enlargement of 1 and 1.5 in. 

 pipe to a pipe whose diameter is 2.096 in., and a study of the action of the Pitot 

 tube under disturbed conditions, are reported. The following conclusions are 

 dra\vn : 



" The Pitot tube measures with a fair degree of accuracj', always within 

 2 or 3 per cent and more frequently within 1 per cent, the velocities of flow in 

 a pipe where the resultant motion of the water throughout the entire cross sec- 

 tion at the point where the tube is inserted is a forward motion, and where the 

 distribution of velocities is symmetrical about the axis of the pipe. The Pitot 

 tube is a means by which eddies or whirls caused by obsti'uctlons in the pipe 

 may be detected, but it will not measure with any degree of accuracy the dis- 

 charge of a pipe when inserted in the immediate region of such eddies. 



" The rating coefiicient of discharge of the Pitot tube for normal conditions 

 can not be applied in the case of abnormal conditions produced by sudden en- 

 largement where eddies exist, but immediately below the region of eddies the 

 rating coefficient of discharge may be applied with a fair degree of accuracy. 

 The eddies produced by sudden enlargement of section extend for the short dis- 

 tance of only about 2 or 3 diameters below the enlargement. The disturbance 

 caused by sudden enlargement of section produces abnormal conditions in the 

 distribution of velocities which continue down the pipe for a distance of about 

 35 diameters. 



" The ratio of the mean velocity to the velocity at the center, -^, increases 



in value, in the case of sudden enlargement, from a minimum near the point of 

 enlargement to a maximum at a point about 11 diameters downstream, after 

 which it begins to gradually decrease, approaching the value of the ratio for 

 flow in straight pipe at a distance of 85 diameters below enlargement. The 

 loss of head due to sudden enlargement may be expressed by the equation, 



Hb=K( -l)-2^ a constant times the theoretical loss by Borda's formula, 



and in making the observations for the total loss due to this disturbance, a 



