href="@public@vhost@g@gutenberg@html@files@31999@[email protected]#Footnote_70_70" class="fnanchor pginternal" tag="{http://www.w3.org/1999/xhtml}a">[70] "These two associated bodies possess the true, strict form of one species, though because of the outwardly different aspect and the inequality of the selfsame innate potency, they have hitherto been held to be different ..." Good iron and good loadstone are more similar than a good and a poor loadstone, or a good and a poor iron ore.[71] Moreover, they have the same potency,[72] for the innate potency of one can be passed to the other:[73] "The stronger invigorates the weaker, not as if it imparted of its own substances or parted with aught of its own strength, nor as if it injected into the other any physical substance; but rather the dormant power of the one is awakened by the other's without expenditure." In addition, the potency can be passed only to the other.[74] Finally they both have the same history: