Prof. Magnus's Hydraulic Researches. 99 



whicli foi'Qi an angle with eacli other has not at all engaged his 

 attention. 



28. When, in the apparatus described in § 4, the cap with an 

 aperture of 3 millims. was changed for one with a diameter of 

 6 millims., the tubes being horizontal, and at an angle of 60°, 

 the phfenomenon represented in fig. 11a and b (looked at from 

 above and at the side), showed itself; The surface cfi?/" appeared 

 cm'ved, and had its concavity on the side on which was the thin- 

 ner jet. The surface no longer bisected the angle which the two 

 jets formed, but approached the directioii of the thicker jet, as is 

 seen in fig. 11 Z>. If the axes of both jets were not exactly in one 

 plane, if, for instance, that of the thinner jet were a little higher 

 than that of the thicker, the convexity was turned somewhat 

 downwards, and the concavity could be seen when looked at from 

 above, as shown in fig. Wb. 



29. If the direction of the horizontal tubes remained the same, 

 but if one of them, that for instance which furnished the thinner 

 jet, were raised parallel to itself until the edges only encountered, 

 then the phsenomenon shown in tig. 12 was presented. 



A water sm-face cdf was again formed, but it was almost 

 plane and horizontal, having the form cdf. From the edge df 

 small drops flew off" in large quantities in a tangential direction, 

 which was not the case at the edge cf. 



Explanation of the phcanoinena presented by the encounter of two 

 Jets of diffo-ent diameters forming an angle with each other. 



30. The form of the surfaces resu^ltiug from the encounter of 

 jets of unequal diameter may be easily explained from a consi- 

 deration of the pi'ocess in the case of jets of the same diameter. 



We have seen, § 28, that when two jets of equal diameters, 

 whose axes are in the same plane, meet each other, they produce 

 a water surface which is at right angles to the plane of the axes 

 ab and ap^, fig. 11, and whose direction bisects the angle which 

 these two jets make with each other. But since the mass of the 

 thicker jet is more considerable than that of the thinner, it results 

 that the surface formed by the union of both jets follows more 

 the direction of the thicker one. That part of the thicker jet 

 which is met by the thinner experiences the strongest deviation 

 from its direction. The edges, on the contrary, which do not 

 directly encounter, suff"er also a smaller deviation. Thus is pro- 

 duced the concave form of the suri'ace, and its deviation from the 

 line jiq, which bisects the angle made by the two axes. 



31. If the thinner jet met the thicker only at its edge, § 29, 

 botli, after their encounter, would retain their directions if the 

 surface formed between them, and spread out like a membrane, 

 cdf, fig. 12, did not hinder it. Since this surface, in consequence 



