toy 



J40TI0NS or FLUIDS. 



crcifed in olive 

 «il. 



a drop of volatile alkali to the centre. What was my furprife 

 to obferve, that the llighteft motion was not manif'efled in the 

 vater; 1 however fufpeded the caufe, and believed that this 

 apparent anomaly was owing to the ammonia, which, having 

 a very great affinity with water, combined with it at theinftant 

 of tiieir contact. 



which was ex- 12. I reiolved, therefore, to fubflitute a fluid to the water, 

 which had lefs affinity with ammonia, and I chofe olive-oil, 

 which I had at hand. I again covered the bottom of the 

 plate with a thin layer of this oil, and brought a drop of the 

 ammonia to the centre : the oil was inftantaneoufly repelled, 

 as it had been by the alcohol. 

 Ammonia does J 3. If the plate be wetted with alcohol, and a drop of 

 notrepe a co o . ^j^jj^qj-jI^ j^. p^j. j^^q ^j-|g centre, the alcohol is not repelled, 

 the drop of ammonia flattens, and the two liquors evaporate. 

 I thought I perceived a flight treraulation on the edge of the 

 drop of ammonia. 

 but alcohol re- ] k If the plate be wetted with ammonia, and a drop of 

 pels ammonia, g^^^^^^ol is brought to the centre, the ammonia is repulfed like 

 pure water. It appears, therefore, from this experiment, 

 and the preceding, that the horizontal or lateral force of ex- 

 panfion of the alcoliol is fuperior to that of the ammonia. 

 Olive-oil and ]5. A drop of olive oil put into a wetted plate, did not 



produce any motion in the water. It was the fame with water 

 beat up with oil to the confiflence of an unguent. M. Prtivftf 

 in his memoirs, feems to announce refults obtained with the 

 fixed oils, which are contrary to my experiments, and par- 

 ticularly to thefe. 



I (liall not enlarge farther on experiments which feme may, 

 perhaps, think more curious ' than ufeful. But when the at- 

 tradive powers of yellow amber, or of the loadfione were 

 firfl obferved, neither their importance, nor the afionifliing 

 difcoveries to which they have fince led, were fufpeded. 



water have no 

 repulfive aQion. 



LeiU 



