THE 

 LONDON, EDINBURGH and DUBLIN 



PHILOSOPHICAL MAGAZINE 



AND 



JOURNAL OF SCIENCE. 



[FOURTH SERIES.] 



SEPTEMBER 1859. 



XXVII. Hydraulic Researches. — Part II. By G. Magnus, Pro- 

 fessor of Natural Philosophy in the University of Berlin^. 



[With Two Plates.] 



On the swellings foi'med in jets issuing from circular orifices. 



116. TN the former part of my hydraulic investigations f I con- 

 A sidered the shape of the water-jets. The remarkable 

 forms assumed by streams issuing from angular orifices were 

 there, I think, satisfactorily explained by showing that they 

 depended upon the phsenomena which occur when two jets 

 meet one another at various inclinations. I also described the 

 very much more regular shapes assumed by streams issuing from 

 circular orifices. The singular swellings or " ventral segments " 

 produced in circular jets by the sounding of a musical note, 

 and which occupied the attention of F. Savart J, were there only 

 considered in a general manner. Since then, by examining 

 them with the aid of different appliances, I have succeeded in 

 determining more decisively their nature and their cause. My 

 observations are contained in the following communication. 



Those swellings were especially examined which are formed on 

 vertically-descending streams ; for these, being obtainable with 

 greater regularity and uniformity than others, afford greater 

 security for correct observation. 



117. In allowing the water to flow out, a vessel was employed 

 of 0*4 metre in height and 0'8 metre in diameter, which was 

 placed upon a firm stand of strong wood, 1-75 metre in height. 

 This vessel is more fully described in Part I. § 40. As there 



• Translated by Dr. F. Guthrie, fiom PoggendorfF's Annalm, vol. cvi. 

 p. 1. 



t Phil Mag. ser. 4. vol. xi. pp. 89, l/B. 



X Ann. de Chim, el de Phys. 2nd series, vol. liii. p. 337- 



Phil, Mag. S. 4. Vol. 18. No. 119. Sept. 1859. M 



