Mr. C. Tomlinson on the Cohesion-Figures of Liquids. 255 



blances are striking : they are of about the same density {i. e. a 

 little heavier than water) ; they are about equal in liquidity or 

 cohesion, and they are both sparingly soluble in water. Now 

 the cohesion-figures of these two substances are so much alike 

 that a casual observer would declare them to be identical. (See 

 Plate.) There are the same crispations in the oil of cloves as in the 

 drop of creosote; the same flattened, indented, waving, agitated 

 outline; the same sailing about ; a similar film, and the same re- 

 pulsion of the film ; the same whirling off of small globules, and 

 the rapid rotation and disappearance of those small bodies. Like 

 the creosote, too, the second drop of oil of cloves reproduces the 

 phenomena of the first in a mitigated form, and is much longer 

 in disappearing. But now for the differences. The film formed 

 by oil of cloves is more like smoke, more dense, persistent, and 

 plicated than that of creosote; and being constantly driven about 

 by the parent disc, it becomes powdery, like fine flour, on the 

 surface of the water. In the midst of this film, the parent glo- 

 bule will sometimes remain for several minutes, keeping a clear 

 space of considerable extent all around it, pulsating in a regular 

 manner, and flashing out lines which are visible only by the 

 motions of the water. But the most considerable difference 

 between oil of cloves and creosote is in their respective duration. 

 We have seen that 2 ozs. of New River water will dissolve three 

 drops of creosote ; the same quantity of river water will not dis- 

 solve so much as two drops of oil of cloves. After the first drop 

 has disappeared, a second will be lively at intervals during nearly 

 an hour, but after twenty-four hours some small lenticules of the 

 oil will remain on the water. Hence oil of cloves has only about 

 half the solubility of creosote in water — only half the adhesion, in 

 fact; but being denser than water, it tends to sink, and thus ap- 

 pears to be more adhesive than it really is. An interesting result 

 may also be obtained with ol. pimentse, which is a little heavier 

 than water (1-021 to 1-044). It is much more sluggish than 

 creosote and oil of cloves, but exhibits similar phenomena on a 

 small scale. If, however, the water be heated to about 110° F., 

 we get a large crispating figure of great beauty. There are special 

 characters about it which I do not stop to describe. 



Should any one wish to repeat these observations on oil of 

 cloves, he may have some difficulty in doing so on account of 

 the difficulty of obtaining the pure oil. The oil of the shops is 

 commonly adulterated with the cheaper oils, such as oil of olives 

 or of almonds, or of turpentine ; and I have ascertained that a 

 single drop of oil of olives to twenty drops of oil of cloves is 

 sufficient to prevent the formation of the cohesion-figure, and 

 the display of those curious and interesting motions of the pure 

 oil. Even in cases where the oil is not adulterated, the fixation 



