88 SCIOPTICON MANUAL. 



the stage ; now with a glass rod, or small brush, dipped 

 in any of Judson's aniline dyes, touch the side of the 

 tank gentty, so as to leave a drop on it. This drop, di- 

 rectly as it touches the alcohol, will go straight down for 

 half an inch or so, and then break out into two branches; 

 these again will break in four, and so on, until by the 

 time the dye gets to the bottom of the tank it will have 

 formed some hundreds of delicate branches. As this 

 action is reversed on the screen, the branches appear- 

 ing to shoot upwards, the effect is much heightened. 

 A (Fig. 28), shows the form assumed. By placing at in- 

 tervals of half an inch drops of different colors, as their 

 branches commingle, the effect reminds one of a shower 

 of different colored rockets. If we now take another 

 tank, and fill it with coal oil, and put a drop of fusel 

 oil into it, we get an entirely different figure, as shown 

 at B. The fusel oil is best colored. 



CAPILLARY ATTRACTION can be strikingly shown to a 

 large audience. A series of glass tubes of different sizes 

 are fitted into a piece of wood which rests on the top of 

 the tank, and dips down to near the bottom; when the 

 tank is filled with water, which is best tinted, the dif- 

 ferent heights of the water, according to the fineness 

 of the tubes, will be shown clearly on the screen. The 

 curve shown by the liquid rising between two pieces of 

 glass can be shown in the same manner, the colored 

 water forming a pretty gradation of color between the 

 highest and lowest part. 



CRYSTALLIZATION. By filling the tank with a satu- 

 rated solution of Glauber's salts, and allowing it to cool, 

 it will appear transparent on the screen, but by dropping 

 one small crystal into it the whole mass will be seen to 

 shoot out into beautiful crystals. 



