44^ Dy* Perdval on /^ItraSiion and Repuljion. 



with water, the fluid will remain petfeflly tran- 

 quil, throughout the whole vefTel, although the 

 fame motion be given to it as before. I have 

 frequently repeated this experiment, and have 

 fometimes varied it, by fubftituting reclified fpi- 

 rit of wine, in the place of water. The oil then 

 being the heavier fluid, becomes agitated, whilft 

 the fpirit remains at refl:. Dr. Franklin, who 

 firfl: noticed this Angular phenomenon, informs 

 us, that he fhewed it to a number of ingenious 

 perfons. " Thofe," fays he, " who are but 

 " flightly acquainted with the principles of 

 " hydroftatics, &c. are apt to fancy, immedi- 

 *' ately, that they underfl:and it, and readily 

 " attempt to explain it : But their explanations 

 *' have been different, and, to me, not very 

 " intelligible. Others more deeply fliilled in 

 *' thofe principles, feem to wonder at it, and 

 " promife to confider it. And I think it is 

 *^ worth confidering. For a new appearance, if 

 " it cannot be explained by our old principles, 

 " may afford us new ones, of ufe perhaps in 

 " explaining fome other obfcure parts of natural 

 " knowledge."* It is with diffidence, I offer 

 as a conjedure, that the fad, in queftion, may 

 arife from a repilfive -power , fubfifting-* between 

 the particles of oil and water, and depending 

 pofllbly on the vibrations of that fubtle £Ether, 



* See Dr. Franklin's Letters and Papers on phllofophical 

 fubjefts, p. 438. 



which 



