1662: Jack and Jill

2016-03-30T14:53:05Z

Eruditionfish: Elaborated on why getting water from a hill is weird

{{comic
| number = 1662
| date = March 30, 2016
| title = Jack and Jill
| image = jack_and_jill.png
| titletext = Jill and Jack / began to frack. / The oil boosts their town. / But fractures make / the bedrock shake / and Jack came tumbling down.
}}

==Explanation==
The comic is about the nursery rhyme "{{w|Jack and Jill (nursery rhyme)|Jack and Jill}}". The first verse is:
:Jack and Jill
:went up the hill
:To fetch a pail of water.
:Jack fell down
:and broke his crown,
:And Jill came tumbling after.

The comic makes fun of how it's weird that they go up a hill to fetch water, because water is usually found in valleys rather than on top of hills. Natural water sources, like rivers and streams, flow down from hills, so it shouldn't be necessary to go up the hill to get the water. Similarly, if the water is coming from a well, then building the well at the top of a hill is an odd choice. The ground water table stays at about the same level over smaller areas, so building the well on a hill just means you have to dig further.

The title text is a parody of this first verse, where the names have been switched in the first and last line:
:Jill and Jack
:began to frack.
:The oil boosts their town.
:But fractures make
:the bedrock shake
:and Jack came tumbling down.

This version connects the idea to {{w|hydraulic fracturing}} (or fracking) methods for oil and gas extraction. In these methods, highly pressurized liquids are forced into a given ground stratum (or layer). With enough pressure, the stratum starts to deform and crack. This allows potential gas and oil to flow more freely. The liquid used for fracturing usually also contains materials like sand or ceramics which, once the liquid is removed, will help to maintain the newly formed cracks so as to further allow the desired free movement of oil and gas.

A common {{w|Environmental impact of hydraulic fracturing|side effect of this method}} is that water levels and presence at the surface might be modified. In this comic, water can now be found at the top of the hill. This goes against the usual laws of hydraulics, themselves subject to the laws of gravity, which indicate that water should go down through ground cracks. Thus water is usually found at the bottom of valleys or hills. But in the comic, fracking at the bottom forces the water up, thus explaining why the kids go get water up the hill, which, as [[Megan]] points out, is messed-up {{w|hydrology}}. Also, fracking may cause {{w|induced seismicity}} in the form of {{w|microearthquake}}s, as alluded to in the title text, which is the cause for tumbling down in the title text version.

This is the second Wednesday in a row that [[Randall]] uses two children to make a reference to a serious environmental issue, the first being [[1659: Tire Swing]], about {{w|Tire recycling}}.

==Transcript==
:[Megan is watching as the two kids Jill with hair bun and a ponytail and Jack with spiky hair are walking by her. Jack has a pail in his hand.]
:Jill: Me and Jack are going up the hill to fetch a pail of water.

:[Megan, standing back alone, calls out after them.]
:Megan: Okay, have fun!

:[Megan just stand there for a beat panel.]

:[Megan suddenly realizes something while looking down on the ground.]
:Megan: ... Wait. What the ''heck'' is going on with the hydrology around here?

{{comic discussion}}

[[Category:Comics featuring Megan]]

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1662: Jack and Jill