428 Mr. C. Toinlinson on a new Variety of 



drop is allowed to fall; and these changes may occupy a minute 

 or two. 



The cochineal figure, with its dropping rings and festoons, is 

 exhibited in its most complicated form by some of the essential 

 oils in a column of alcohol, or some other solvent of them. For 

 example, rather more than three fluid-ounces of methylated 

 spirits of wine were poured into a cylindrical glass 6 inches 

 high and 1| inch in diameter, and on the surface of this was 

 deposited, from the end of a glass rod, a single drop of oil of 

 lavender. The drop sank beneath the surface, expanded into a 

 ring No. 1*, passed through the changes Xos. 2 and 3, and 

 then burst like a rocket into a multitude of festoons and small 

 rings. An attempt is made to represent the lavender figure in 

 the Plate, in which will be seen (1) the ring, (2) the same 

 bent down at four equidistant points, from which proceed (3) 

 festooned lines and other systems of rings, and from these last 

 we get (4) a multitude of small rings and festoons. The figure 

 formed by oil of cubebs is even more remarkable. The drop 

 formed a large ring, which split into two or three other rings, 

 each of which broke up into lines and small rings, and a mul- 

 titude of globules descending and dragging trails after them. 

 Oil of cinnamon formed a good ring, which descended before it 

 broke up, leaving a ring of more attenuated matter behind it; 

 just as in the cohesion-figure of this oil on the surface of water a 

 more diffusive oil shoots out beyond the usual figure and forms a 

 fringe to it. The texture of the rings is like that of molten 

 glass or sugar; indeed the term saccharine would express the 

 appearance of the rings and festoons in spirits of wine. In a 

 few cases the rings and lines were chalky, as if the elaiopten 

 were dissolved first and the stearopten were left to do the work of 

 the figure. This effect is produced by oil of peppermint, but is 

 much more marked in columns of other liquids afterwards em- 

 ployed. The rings and lines formed by benzole in spirits of 

 wine are very glassy and wavy. The oils of turpentine and 

 juniper form each a double convex lens, or a very flat spheroid, 

 which descends rapidly and remains at the bottom. The fixed 

 oils also form very flat spheroids. 



T\nen a column of benzole was used, many of the essential 

 oils produced the rings and festoons, but often of an opake 

 white, as if the stearopten alone formed the figure. In some 

 cases the first ring would be glassy and transparent, and then 

 burst into a figure that was chalky or milky. The oils of 

 lavender, coriander, cinnamon, cloves, bergamot, and some 

 others formed smoky rings and festoons. The oils of origanum, 

 rosemary, and some others formed transparent lines and rings. 

 * See oil of lavender, &c., in spirit, in the Plate. 



