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The latest issue of Steampunk Magazine, issue 4, is available now for download (free w/donation encouraged) or for purchase in a print edition for a paltry $3.

This latest issue includes a how-to on building a Jacob's Ladder:

Once the arc starts, the air conducting the arc is both ionized and heated by the current. Ionized air is more conductive than non-ionized air, and heated air tends to rise, so the arc will rise with it. The electrodes slope away from each other, so eventually the gap is too wide to support the arc. It re-forms at the bottom again, where the going is easier, and the cycle repeats. It is truly a wonder to behold, like watching the Devil's own yo-yo!

Although a Ladder serves no direct scientific purpose, having one is a requirement for recognition as a "mad scientist" (the preferred term is "ethically-undaunted science worker") and it is the internationally recognized symbol of "forbidden science in progress." Having one in operation greatly facilitates engaging the services of reliable resurrectionists, infernal device contractors, and members of the International Congress of Hunchbacked Henchmen.

Steampunk Magazine - Link

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