"Mercury doesn't contribute its valence electrons readily to the [electron] soup. The thinner soup can't bind the mercury atoms together very strongly. Mercury atoms easily slip past and away from each other. Heat easily overcomes the weak binding between mercury atoms, and mercury boils and melts at lower temperatures than any other metal. Because the valence electron soup is thinner for mercury, its electrical and thermal conductivity are poor.

"While Paracelsus was pressing his doctrines on all sides, and endeavouring to lead chemistry into a new channel, another, Agricola, was quietly at work among the mines of Saxony, utterly indifferent to all but the advance of his science. It is to Agricola's systematic observations that we trace the beginnings of the science of mineralogy. In metallurgy, also, he was a pioneer, the first to give a clear and succinct account of the preparation of many metals. He taught the condensation and purification of sulphur given off during the roasting of many ores, the separation of silver from gold by means of nitric and sulphuric acid, the preparation of such bodies as salt, alum, and saltpetre on a large scale. The apparatus described by Agricola and employed by him for the smelting and testing of ores were still in use at the end of the eighteenth century. Agricola stands out solitary among the men of his time as one pursuing chemistry from pure love of the science; his work had no other aim than the increase of knowledge.

"Iron yields to certain degrees of beatings or repeated pressure; its impenetrable molecules, purified by man and made homogeneous, disintegrate; and, without being in fusion, the metal no longer has the same virtue of resistance. Marshals, locksmiths, tool makers, all the workers who constantly work this metal then express the state of it by a word of their technology: "The iron is retty!" they say, appropriating this expression exclusively devoted to hemp, the disorganization of which is obtained by retting. Well, the human soul, or if you will the threefold energy of body, heart, and spirit, is in an iron-like situation, as a result of certain repeated shocks. It is thus with men like hemp and iron — they are retty.