1862.J 251 



VI. " On the Causes of various Phenomena of Attraction and 

 Adhesion, as exhibited in Solid Bodies, Films, Vesicles, 

 Liquid Globules, and Blood-Corpuscles." By RICHARD 

 NOREIS, Esq., Birmingham. Communicated by Dr. 

 SHARPEY, Sec. R.S. Received August 28, 1862. 



It has long been observed that solid bodies floating on liquids 

 possess the property of modifying the figure of the surface of the 

 liquid ; thus pieces of tinfoil or greased bodies depress the liquid 

 around them, while many others by the exercise of an attraction for 

 its particles elevate it, giving rise to small mounds of liquid bounded 

 by concave lines. It has also been observed that likes attract likes 

 and are repelled by unlikes, i. e. bodies having like or unlike powers of 

 altering the figure of the surface. These phenomena are generally 

 admitted to depend for their existence on the combined forces con- 

 cerned in capillary attraction. The following experiments are 

 arranged to show that these effects of attraction are not peculiar to 

 floating bodies or to bodies partially immersed, and that the only re- 

 quirement is that liquid should be associated with the bodies in which 

 the movement occurs. 



Exp. 1. Let two balls of sealing-wax,"or other material of greater 

 specific gravity than water, be suspended by hairs in such a manner 

 that they will both be partially immersed in water to an equal extent, 

 the points of suspension being at a little distance apart, and the 

 suspending hairs consequently parallel. When brought within the 

 proper range, they will attract each other in the same manner as the 

 floating bodies. In doing so they necessarily describe a small arc 

 of a circle, of which the suspending hair is the radius, and have 

 therefore not simply moved towards each other in a horizontal line, 

 but have been raised to a higher level. 



Exp. 2. Let two small sheets of microscopic glass be applied to 

 each other by their lower edges so as to form an acute angle like the 

 letter V, and let them be supported in this position by pins. On 

 placing a drop of water in the angle, the plates will be drawn toge- 

 ther and cohere by their surfaces. 



Exp. 3. Suspend moveably, by means of a thread passing over a 

 pulley and a small counterbalancing weight, a horizontal cork disk, 



T2 



