1882.] 



On Impact with a Liquid Surface. 



347 



The percentage of nickel is high ; but it is pointed out that in the 

 nickel-iron present in meteoric stones the nickel rises in quantity as the 

 quantity of nickel-iron falls. The remaining constituents consist of 

 rocky matter, amounting to 90*621 per cent., and are soluble silicate 

 54 , 315 per cent, and insoluble silicate 36*306 per cent. The soluble 

 silicate appears to be an olivine of the form 2(|Pe,§Mg)0,Si0 2 , or 

 one closely resembling that which occurs in the Lance stone, which 

 fell July 13th, 1872, and was examined by Daubree. The insoluble 

 part is chiefly bronzite, and most closely resembles that which is to be 

 found in the meteorites of Iowa co., Iowa, east of Marengo, which 

 fell 12th February, 1875, and were examined by Dr. L. Smith. The 

 aluminium constituent is doubtless labradorite, and is probably 

 present as some of the occasional chondra which are seen in a micro- 

 scopic section. 



A plate showing three views of the stone accompanies the paper. 



February 16, 1882. 



THE PRESIDENT in the Chair. 



The Presents received were laid on the table, and thanks ordered 

 for them. 



The following Papers were read : — 



I. " On Impact with a Liquid Surface." By A. M. WORTHING- 

 TON, M.A. Communicated by Professor Osborne Reynolds, 

 F.R.S. Received January 27, 1882. 



(Abstract.) 



The apparatus previously used* by the author for following the 

 progress of the splash of liquid drops impinging on a solid plate has 

 been improved. The main principle of the method by which succes- 

 sive stages are isolated and rendered visible remains the same, viz., 

 instantaneous illumination at any desired stage by means of the 

 primary spark of an induction coil ; but the timing of the illumination 

 is now effected by a timing-sphere let fall simultaneously with the 

 solid or liquid sphere whose impact is to be observed. The timing- 

 sphere strikes a plate whose height can be adjusted, and thereby 

 starts the mechanical action which results in the spark. 



* " Proc. Roy. Soc," vol, 25, pp. 261, 498. 



