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(116) April 22nd 1844 [[image]] with a piece of the same wire left projecting, and this be dipped into a strong solution of soap, a film will be drawn up and the great tenacity of the liquid may be shown by throwing on the film a quantity of cotton, or some light substance, which is not readily wet with water- a considerable weight will be borne before rupture. [[image]] If the same wire be dipped into ^[[the soap]] water [[strikethrough]] then [[/strikethrough]] edge-wise, the liquid will be observed to mound along the sides ^of the film^ as it would along the surface of a plate of glass plunged in the same manner into the liquid. This illustrates the fact that the support of the water in the capillary action is due to the attraction of the liquid for itself, or at least in a considerable or I should say principal degree; according to the theory of Poisson, the solid does have some effect, but I should think its imperceptible. The bubble while in a state of tension cannot be brought readily into the sphere of attraction, this is shown by touching the lower part of a bubble to the film across the ring of wire, the two will not coalesc, but if a drop of water be pendant from the lower side of the bubble, union instantly takes place. [[image]] Another experiment of some interest may be exhibited, showing the attraction and repulsion of the film forming the bubble. Two bubbles may be blown in a ring (one however is sufficient for the experiment), and soap water may be poured on this in a stream the 1/8 of an inch in diameter; without [[end page]] [[start page]] April 22nd 1844 (117) breaking it. If the liquid be poured on so as to strike the side of the bubble, it will be reflected off as if repelled. If the stream strike the top of the bubble, it will pass entirely through, and although the bubble will be violently agitated, it will not break, if the operation be conducted with proper caution. In the second case, the water comes within the attraction distance and unites with the film, so that the exterior and contractile [[sufferance?]] of the liquid and the surface of the bubble form one extended surface. The same experiment may be exhibited by means of the ring of wire across which a film of soap suds is stretched. For this purpose the water may be poured from a cup with a lip in a continued stream, and if the operation be carefully performed, the film will not be broken although much agitated. [[image]]A pretty exhibition is produced by attaching a bladder to a ring, and then thrusting a pipe into the upper end of it, which may be readily effected if the pipe be wetted, and then blowing a second bubble. The two will swell together, and show a brilliant set of iridescent colours. Why does the bubble spread when it touches the surface? Because the attraction of the sides of the [[strikethrough]] water [[/strikethrough]] bubble draws up the water by capillary attraction, and more is accumulated on the outside than on the inside, and because the sides are constantly drawn out until they become perpendicular to the flat surface of the plate on the water. See figure in margin. [[image]] [[end page]]
Transcription Notes:
This is the same image as page 61 of 195, just scanned without the note covering up the writing
