November 2013

* De Re Metallica

"The educational system is our weapon of choice for dismantling delusions."
(Cosimo De Winter)


The Book De Re Metallica had a fundamental purpose, and that was explaining to princes and the aristocracy the wealth that can be gained from the art of mining for metals. Agricola explains that mining and prospecting are not just a matter of luck and hard work; there is specialized knowledge that must be learned. A miner should have knowledge of philosophy, medicine, astronomy, surveying, arithmetic, architecture, drawing and law, though few are masters of the whole craft and most are specialists. In the book are philosophical objections to gold and silver as being intrinsically worthless. The book has objects to the danger of mining to its workers and its destruction of the areas in which it is carried out. He argues that without metals, no other activity such as architecture or agriculture are possible. The dangers to miners are dismissed; most deaths and injuries are caused by carelessness and other occupations are hazardous too. Clearing woods for fuel is advantageous as the land can be farmed. Mines tend to be in mountains and gloomy valleys with little economic value. The loss of food from the forests destroyed can be replaced by purchase from profits, and metals have been placed underground by God and man is right to extract and use them. Finally, Agricola argues that mining is an honorable and profitable occupation.

The book also describes the miner and the finding of veins. Agricola assumes that his audience is the mine owner, or an investor in mines. He advises owners to live at the mine and to appoint good deputies. It is recommended to buy shares in mines that have not started to produce as well as existing mines to balance the risks. The book recommends areas where miners should search. These are generally mountains, but with wood available for fuel, and also a good supply of water. The roads must be good and the area healthy. Agricola describes searching streams for metals and gems that have been washed from the veins. He also suggests looking for exposed veins and also describes the effects of metals on the overlying vegetation. He recommends trenching to investigate veins beneath the surface. He then describes dowsing with a forked twig although he rejects the method himself. Finally he comments on the practice of naming veins or shafts.

This book also describes smelting, which Agricola describes as perfecting the metal by fire. The design of furnaces is first explained. The furnace is charged with beneficiated ore and crushed charcoal and lit. In some gold and silver smelting a lot of slag is produced because of the relative poverty of the ore and the tap hole has to be opened at various times to remove different slag materials. When the furnace is ready, the forehearth is filled with molten lead into which the furnace is tapped. In other furnaces the smelting can be continuous, and lead is placed into the furnace if there is none in the ore. The slag is skimmed off the top of the metal as it is tapped.

The lead containing the gold is separated by cupellation, the metal rich slags are re-smelted. Other smelting processes are similar, but lead is not added. Agricola also describes making crucible steel and distilling mercury and bismuth in this book.

Agricola describes parting silver from gold in this book by using acids. He also describes heating with antimony sulphide (stibium), which would give silver sulphide and a mixture of gold and antimony. The gold and silver can then be recovered with cupellation. Gold can also be parted using salts or using mercury. Large scale cupellation using a cupellation hearth is also covered in this book.

(De Re Metallica,
by Herbert and Lou Hoover

Herbert Hoover


"About the time we can make the ends meet, somebody moves the ends."

"Older men declare war. But it is the youth that must fight and die."

"Competition is not only the basis of protection to the consumer, but is the incentive to progress."

"When we are sick, we want an uncommon doctor; when we have a construction job to do, we want an uncommon engineer, and when we are at war, we want an uncommon general. It is only when we get into politics that we are satisfied with the common man."


"Freedom is the open window through which pours the sunlight of the human spirit and human dignity."

"It is just as important that business keep out of government as that government keep out of business."

"It is the youth who must inherit the tribulation, the sorrow... that are the aftermath of war."

"This is not a showman's job. I will not step out of character."

"No public man can be just a little crooked."

"I'm the only person of distinction who has ever had a depression named for him."

"Let me remind you that credit is the lifeblood of business, the lifeblood of prices and jobs."

Lou Hoover

"The independent girl is a person before whose wrath only the most rash dare stand, and, they, it must be confessed, with much fear and trembling. A most bewitching little piece of humanity."

"I was a Scout years ago, before the movement started, when my father took me fishing, camping and hunting. Then I was sorry that more girls could not have what I had. When I learned of the movement, I thought, here is what I always wanted other girls to have."

"I majored in geology in college but have majored in Herbert Hoover ever since."

Power of the Witch

"The Olympian gods were not bored, they lived happily in happy idleness. A beautiful woman, who neither sews nor spins nor bakes nor reads, nor plays the piano, is happy in her idleness, for she is not bored. So far from idleness being the root of all evil, it is rather the only true good. Boredom is the root of all evil, and it is this which must be kept at a distance. Idleness is not an evil, indeed one may say that every human being who lacks a sense for idleness proves that his consciousness has not yet been elevated to the level of the humane. There is a restless activity which excludes a man from the world of the spirit, setting him in a class with the brutes whose instincts impel them always to be on the move. There are men who have an extraordinary talent for transforming everything into a matter of business, whose whole life is business, who fall in love, marry, listen to a joke, and admire a picture with the same industrious zeal with which they labour during business hours. The latin proverb "idleness is the devils pillow" is true enough, but the devil gets no time to lay his head on this pillow when one is not bored. But since some people believe that the end and aim of life is work, the disjunction, idleness-work, is quite correct. I assume that it is the end and aim of every man to enjoy himself, and hence my disjunction is no less correct."
(Soren Kierkegaard)