SIR G. GREENHILL ON ELECTROMAGNETIC INTEGRALS. 



37 



Fig. 4. 



This was carried out by Mr. J. W. HICKS for comparison with MAXWELL'S figure 

 using the formulas given later in 12. 



The same confocal co-ordinates on the Weir chart were employed by Colonel 

 HIPPISLEY in drawing fig. 3 and 4, and the lantern slides, showing the lines of 

 uniplanar flow past an ellipse ; but here the co-ordinate ruling has been rubbed out. 



G 2 



