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[[image – drawing to the left of handwritten notes, depicting plates and hourglass shaped figure with rings labelled "a"]] 118 If two plates or films of soap water be dipped into the soap water, the liquid we might suppose would be elevated between them, as if it were between two plates of glass, but this I find not to be the case, the two films are drawn together by the attraction of the water.* When a large bubble attached to the ring [[underline ]] a [[/underline]] touched at its lower point to the surface of a moistened plate, the bubble adheres and spreads out as in the figure. If now it be drawn upward by the ring, it will be observed to contract at about [[underline]] b [[/underline]], and grow smaller and smaller at this point as the ring is lifted upwards, and finally it separates into two parts, leaving a hemisphere on the plate and a smaller spherical bubble on the plate. To explain this action, we may imagine the bubble made up of a series of rings which tend to contract by the contractile force of the surface into a smaller dimention. The difference between a bubble of pure water and one of soap water, may be illustrated by the comparison of an arch in the one case formed of parts or wedges without friction, and in the other of parts which have lateral adhesion similar to friction. In the first case, the arch will have the same inward pressure, but will be instable and in the second stable. [[image – drawing of a hand pointing to left of handwritten notes]] Make bubbles of gum water. A bubble may be prolonged in existance by blowing under it in the air, so as to cause it to roll over, making the lower part the upper. T Dean Bubble of gum water, also film of the same [[word circled]] dried [[word circled]] T. Dean *This experiment has a bearing on the question of the circulation. [[end page]] [[start page]] July 5 1844 119 Prepared this morning the apparatus to attempt to get the interferance of [[circled]] cold [[circled]], but before I was fully prepared to operate, the sun failed me and I was obliged to give up the experiment for today. I next drew a copper wire from Mr. Clow's well to the electrical machine across the room. When sparkes were thrown on the ball on the end of this wire, sparks could be drawn from all along it towards the well, inconformity with what I have before published. The wire was afterwards opened, and one of the intensity wire inductric spirals placed in the space. A pain of glass was placed over this, and a second spiral on this again. The result was the same as that which I had previously observed, but with the additional fact that the electricity tends to fly off from the secondary wire in the same manner, as from the primary wire. This is a new fact, and appears to have a bearing on the facts of the lateral discharge. The experiment was varied by disconnecting the long wire leading to the well, and sending the charge directly through the spiral from a Leyden jar. The result was the same, the sparks were given off. [[drawing - wires connected to a flat surface with an item in between them]] In the afternoon of this day I repeated an experiment described to me in a letter from Dr. OSchaunessey of Calcutta, which is as follows: A discharge of electricity from a battery of 6 jars is passed through a slip of tin foil of about an inch wide, and 6 inches long, when the foil is dry, the discharge passes silently, but when the foil is wet, a bright flash is seen along the surface - when percussion powder (silver salt) is sprinkled along the surface, an explosion takes place when the foil is wet, but not when dry. [[end page]]
Transcription Notes:
The name of the Calcutta Scientist transcribed as OShaunessey seems to be not very appropriate for a person from that place. O S Chemeneney might be closer.
