Hydraulic Analogy
Hydraulic Analogy
[Miss Lenhart stands next to a white board with two diagrams while pointing to the first. While she is explaining Cueball interrupts her from off-panel as seen by his voice coming from the right side out of a starburst on the panels edge. The diagrams are a schematic circuit diagram and a water flow diagram. There is a battery (with labels on top and bottom) on the left and a resistor on the right of the circuit as well as labels on each of these and one at the top part of the wire. There is a pump to the left and a tighter section of the pipe to the right, as well as labels on these and on the top part of the pipe. At the bottom there is two arrow pointing in towards the pipe, this also has a label.] Miss Lenhart: Electric current is like water flowing in a pipe. The pressure represents- Cueball [off-panel]: Wait, hold on. Labels on circuit: + - V I R Labels on flow diagram: Pump F R D
[The view changes so Miss Lenhart and the white board are seen from the side. She still stands next to the white board, arms now down, as Cueball approaches the board with a marker held in one hand. The diagrams can still be seen, but distorted from being viewed from the side, and no labels are readable.] Cueball: Do you mind if I just...
[Zoom in on Cueball, who is drawing on the white board, which is the left edge of the panel, i.e. not visible in the panel. Noises from the marker drawing on the board comes up from the tip of the marker pen. The movement of the pen is indicated with small lines on either side.] Scribble Scribble Scribble
[Miss Lenhart and Cueball, holding the marker pen down, stand on either side of the white board looking at Cueball's version with the merged diagram. He has connected the two, so instead of the wire going down after the resistor in the circuit diagram, it now is connected with water flowing to the right just below the resistor, and then up into the pump to the right of the resistor. At the bottom where the water pipe before bent up into the pump, the water now continues running to the left (the pipe was not drawn around it by Cueball), and it now flows where the bottom part of the wire, from the circuit, was before, turning up below the battery and connecting with it there. All the labels from before have been retained as follows.] Labels on diagram: + - V I R Pump F R D
[Miss Lenhart and Cueball stand on a podium with a Cueball-like presenter. The presenter is holding two Nobel Prize medals up in his hands. He is holding them from the strings they are attached to, so the medals hang below his hands.] Presenter: And for the design and construction of the liquitricity device, the Nobel Prize goes to...

Electric flow is commonly represented by a " hydraulic analogy ". In this analogy, the water pressure represents voltage and the flow of the water is the current . Electric resistance is represented by a constricted section of a pipe.
Miss Lenhart is teaching a class and starts to explain this analogy when Cueball suddenly has an idea and changes her diagrams - connecting the electrical diagram and the hydraulic diagram. In doing this, he has envisioned what comes to be called a "liquitricity device", combining liquid water and electric current flows together and given a suitably portmanteau title.
The last panel shows that Miss Lenhart and Cueball eventually receive the Nobel Prize , presumably the Nobel Prize in Physics , for the design and construction of the device - indicating that rather than being purely theoretical it has actually been practical to make this device.
The title text 'explains' how this device works and references Ohm's Law , one of the fundamental laws of electricity, but strangely seems as much an incomprehensible mix of the two as the diagram in explaining whatever form of possible duality it actually employs.
One of the featured Footer comics , 730: Circuit Diagram , displays a very complex circuit diagram. Although no pump or direct water flow can be found here, it all ends up in a beaker with holy water. And there is a symbol labeled 3 liters, at the bottom close to the beaker. This is the symbol for an orifice or flow restriction used on plumbing or hydraulic diagrams. So Randall already mixed water flow and circuit diagrams over 10 years ago.
[Miss Lenhart stands next to a white board with two diagrams while pointing to the first. While she is explaining Cueball interrupts her from off-panel as seen by his voice coming from the right side out of a starburst on the panels edge. The diagrams are a schematic circuit diagram and a water flow diagram. There is a battery (with labels on top and bottom) on the left and a resistor on the right of the circuit as well as labels on each of these and one at the top part of the wire. There is a pump to the left and a tighter section of the pipe to the right, as well as labels on these and on the top part of the pipe. At the bottom there is two arrow pointing in towards the pipe, this also has a label.] Miss Lenhart: Electric current is like water flowing in a pipe. The pressure represents- Cueball [off-panel]: Wait, hold on. Labels on circuit: + - V I R Labels on flow diagram: Pump F R D
[The view changes so Miss Lenhart and the white board are seen from the side. She still stands next to the white board, arms now down, as Cueball approaches the board with a marker held in one hand. The diagrams can still be seen, but distorted from being viewed from the side, and no labels are readable.] Cueball: Do you mind if I just...
[Zoom in on Cueball, who is drawing on the white board, which is the left edge of the panel, i.e. not visible in the panel. Noises from the marker drawing on the board comes up from the tip of the marker pen. The movement of the pen is indicated with small lines on either side.] Scribble Scribble Scribble
[Miss Lenhart and Cueball, holding the marker pen down, stand on either side of the white board looking at Cueball's version with the merged diagram. He has connected the two, so instead of the wire going down after the resistor in the circuit diagram, it now is connected with water flowing to the right just below the resistor, and then up into the pump to the right of the resistor. At the bottom where the water pipe before bent up into the pump, the water now continues running to the left (the pipe was not drawn around it by Cueball), and it now flows where the bottom part of the wire, from the circuit, was before, turning up below the battery and connecting with it there. All the labels from before have been retained as follows.] Labels on diagram: + - V I R Pump F R D
[Miss Lenhart and Cueball stand on a podium with a Cueball-like presenter. The presenter is holding two Nobel Prize medals up in his hands. He is holding them from the strings they are attached to, so the medals hang below his hands.] Presenter: And for the design and construction of the liquitricity device, the Nobel Prize goes to...
