408 Mr. C. Tomlinson on some Phenomena connected uith 



Oil of cajeput forms a good film on the surface of water, nearly 

 covering it. A drop of creosote at the side slowly made its way 

 into the film, which retreated from it, waving backwards and 

 forwards as if reluctant to be displaced. The creosote lens gra- 

 dually flattened down, and in ten minutes became active, sailing 

 about and repelling the film, which gathered up into disks. The 

 figure was very active, producing that flashing kind f motion 

 on the surface already alluded to, and clearing a wide circuit of 

 water for its own operations. Small pellets from the figure fu- 

 riously invaded the film, cutting it up, and rapidly disappearing 

 in the process. The figure continued active during eight minutes, 

 thus making eighteen in all from the first putting on of the creo- 

 sote. The cajeput disks now flattened out into films; a second 

 drop of creosote made them collapse; a second drop of cajeput 

 formed a film which arrested the motions of the second creosote 

 figure; and as the film became thinner by evaporation, it was 

 curious to notice the creosote gradually becoming active. First 

 the edge of the lens became uneasy with nervous twi tellings, 

 then it became a little ragged, and suddenly the whole figure 

 started into life. A third film and a third figure went through 

 their operations on the same surface, the duration of each being, 

 of course, prolonged. 



The experiment was repeated with water at 75°; and the di- 

 minished adhesion was shown by the cajeput film now occupy- 

 ing less than half the surface instead of the whole. The creo- 

 sote formed a lens as before, which made its way into the film 

 and, gradually flattening, became active. 



The film produced by oil of Myristica also shows these effects 

 exceedingly well. 



Oil of savin, oil of juniper, and several others formed films 

 which permanently arrested the motions of the creosote figure; 

 but on redistilling these oils so as to get rid of oxidized products, 

 smaller films were formed, showing how greatly they had improved 

 in cohesive force by being purified. When the savin film was 

 first on the surface, the creosote figure made it contract into a 

 lens. When the creosote figure was on first, the film arrested 

 its motions for a second or so, but the figure, becoming active, 

 shut up the film. The figure also shut up the juniper film; 

 but, as in some other cases, if the creosote figure first had pos- 

 session of the surface, the drop of juniper formed a small well- 

 shaped lens. 



Newly distilled oil of coriander forms a beautiful cohesion- 

 figure on the surface of water. The drop spreads rapidly out 

 into a film of large size; then the edge breaks into a regular 

 and somewhat serrated character, and the film contracts rapidly, 

 leaving the serrations long and thin. Some of the spaces be- 



