in Fluids. 351 



guished from the brine, remained perfectly separated from 

 this heavier saline liquor, on which it reposed quietly, 

 without the smallest appearance of any tendency to mix 

 with it. 



I now filled to the height of about 5 inches -the void 

 space between the outside of the small jar and the inside 

 of the large jar in which it was placed with ice-cold 

 water, mixed with a quantity of ice, in pieces as large as 

 walnuts (pounded ice would have obstructed the view m 

 observing, through the sides of the large jar, what passed 

 in the smaller), and when this was done, I very carefully 

 poured ice-cold olive oil* into the smaller jar till it cov- 

 ered the surface of the (tinged) fresh water to the height 

 of about an inch (see Fig. 5, Plate IV.) ; and placing 

 myself near the table, in a situation where I had a dis- 

 tinct view of the contents of the small jar, I set myself 

 to observe the result of the experiment. 



After waiting above an hour without being able to 

 perceive the smallest appearance of any motion, either in 

 the brine or in the fresh water (the one continuing to 

 repose on the other with the most perfect tranquillity, 

 and without the smallest disposition to mix together), I 

 left the room. 



When I returned to it the next day, I found things 

 precisely in the state in which I had left them ; and they 

 continued in this state, without the smallest appearance 

 of any change, or of any disposition to change, during 

 four days. 



At the end of that time, thinking that any farther 

 prolongation of the experiment would be quite useless, 

 I removed the small jar, taking care not to agitate its 



* This oil served not only to keep the water on which it reposed quiet, but also 

 to prevent any communication of heat between it and the air of the atmosphere. 



