ArticleslgStudy

physics

John D. Hamaker

John D. Hamaker is a physics topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand John D. Hamaker rather than just read about it. In short: John D. Hamaker (1914–1994), was an American mechanical engineer, ecologist, agronomist and science writer in the fields of soil regeneration, rock dusting, mineral cycles, climate cycles and glaciology.

Key takeaways

  • John D. Hamaker belongs to physics; place it in that map before memorising details.
  • Learn the definition first, then one example that makes the definition concrete.
  • Connect John D. Hamaker to a quantity you can measure, compute or draw — that is where exam questions come from.
  • Reproduce the core statement of John D. Hamaker from memory before moving on to harder problems.

Reference excerpt

John D. Hamaker (1914–1994), was an American mechanical engineer, ecologist, agronomist and science writer in the fields of soil regeneration, rock dusting, mineral cycles, climate cycles and glaciology.

Biography

Background Hamaker was born in St. Louis, Missouri, United States, and graduated from Purdue University in Mechanical Engineering. Concerned for the environment, he became a student of ecology and agriculture and was influenced by books such as Bread From Stones, which showed that plants grow better in soils generated by mimicking natural soil-forming processes that take millennia, such as the advance and retreat of glaciers scouring the Earth's crust, or rock weathering of volcanic lava. In the 1960s, Hamaker cultivated an interest in soil and climate issues, and began publishing articles about how the health of an individual, society and planetary ecology thrive only as an interdependent whole. For 30 years, he wrote and campaigned for organic agriculture based on soil remineralization, and was the first to call for the remineralization of the Earth to forestall the next glacial period within the current ice age cycle. He produced a book, The Survival Of Civilization, in 1982, republished in 2002 as Remineralize The Earth.

Early developments In the 1970s, a series of scientific conferences concluded that the world's climate was cooling. Books such as The Cooling, The Weather Conspiracy, The Weather Machine & The Threat Of Ice, Climates Of Hunger, Ice Ages and Climate: Present, Past & Future warned of a coming ice age within decades. In 1975, Newsweek ran an article entitled "The Cooling World" that foretold the decimation of agricultural productivity based on a dramatic decrease in the Earth's temperature. and the New York Times published the article "Scientists ask why world is changing; Major cooling may be ahead". In parallel, books such as A Blueprint for Survival, The Limits To Growth, and The Population Bomb, warned of multiple social, economic, ecological and population crises. At the same time, Hamaker continued to generate articles and bulletins and campaign for the remineralization of the world's soils. According to his writings, in 1976, Hamaker spread rock dust on part of his 10 acres (40,000 m2) in Michigan. The following year, his corn produced 65 bushels per acre, compared to yields of under 25 from other local farms, and also tested higher in many minerals. He calculated that remineralizing the soil with river, seashore, mountain and glacial rock dust would enable American agriculture to produce four times as much food or the same amount with a 25% reduction in cost, without the need for pesticides or chemical fertilizers.

The Survival Of Civilization In 1982, he produced with Californian ecologist Donald A. Weaver The Survival Of Civilization: Carbon Dioxide, Investment Money, Population – Three Problems Threatening Our Existence, which was re-published by Remineralize The Earth in 2002 and in 2006 by SoilandHealth.org. Annotations and supporting evidence were provided by Weaver. The book which initially sold 14,000 copies, concerned the threat of an imminent ice age, remineralizing the world's soils on a local and global scale and reforesting the planet to return atmospheric carbon dioxide to a normal interglacial level near 280 ppm, to help slow the glacial advance. The treatise was a synthesis of Hamaker's thinking that emerged from his studies and research in several disciplines including soil science and paleoclimatology. His message, dubbed the Hamaker Thesis, was that due to modern agricultural and agro-forestry practices, the soils were running out of minerals, causing the dying and burning of forests worldwide and nutrient deficiencies in food. He offered soil remineralization as a solution, advocating regeneration of soil and forests with rock dusts as an economic and ecologically sustainable alternative to chemical fertilizers and pesticides. Hamaker regarded this as one of the most powerful ideas in human history. The book and its message was well received by soil and nutritional scientists and regarded as a blueprint for restoring the planet's ecological integrity by the worldwide remineralization movement.

Testimonials Endorsing the book, Buckminster Fuller, inventor of the geodesic dome, author of the book Critical Path and Professor Emeritus at the University of Pennsylvania, wrote in a publicized letter to Donald Weaver in 1983: "I have received and read John Hamaker's The Survival of Civilization. Well done. Completely convincing.... I will tell all those inquiring of me about matters relevant to our survival that they had best read Hamaker's book." Reviewing the book, writer Bertram Cohen expressed concern that a global climate shift would make the temperate zone part of the sub-arctic zone and deprive humanity of its food supply. Cohen also pointed out that "Dr Herbert Shelton, both in his books and in Hygienic Review, emphasised the importance of soil remineralization in creating a Hygienic Agriculture." In support of the book, The Earth Renewal Society presented a statement to a Congressional hearing in Chicago in March 1984.

Discoveries and inventions

Rock medicine Hamaker believed remineralizing the world's soil with rock dust, a quarrying by-product, could revitalise barren soil and reverse climate change. Rock dust nourished soil micro-organisms whose protoplasm is the basis of all living things. When mixed with compost, the dust created rich, deep soils which could produce high growth vegetation free from pests and predators, at an accelerated rate. The idea was later confirmed by agricultural scientists such as Arden Andersen, who showed how high sugar and mineral levels in soil gave immunity to soil bacteria, stopping insect and fungal attacks. For Hamaker and Andersen, minerals were the primal food for micro-organisms which provided life and health for the soil.

Rock grinders Hamaker invented an autogenous rock grinder, designed to grind rock upon rock with minimal wear of metal parts, and a macro version, both for creating rock dust. The full design for the rock grinder was described in The Survival Of Civilization and Donald Weaver's To Love And Regenerate The Earth. On 19 October 1984, China's Research Institute of Forests accepted a copy of Hamaker's rock grinder patent papers, since at the time, China was taking the lead in reforestation programs.

Scientific basis

… excerpt ends here. Continue reading the full article.

Worked examples

Example 1 — a first encounter with John D. Hamaker

Start with the simplest possible case. Write down what John D. Hamaker claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In physics, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to John D. Hamaker before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about John D. Hamaker ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of John D. Hamaker

In research
John D. Hamaker appears in physics research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry
Engineering practice reuses John D. Hamaker in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom
John D. Hamaker is common in secondary-school and first-year university syllabi. It links to neighbouring topics 1914 births, 1994 deaths, 20th-century American agronomists, so understanding it makes those chapters shorter.
In everyday life
Look for John D. Hamaker outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.
Ask Teacher Smith questions about this articleOpens your AI tutor with a question about “John D. Hamaker” →

Affiliate

Preply — study more efficiently by working with a personal tutor. 50% off.

How to study John D. Hamaker in 20 minutes

  1. Read the reference excerpt below once, without taking notes.
  2. Close the page and write down what John D. Hamaker means in your own words.
  3. Compare your version with the excerpt and mark what you missed.
  4. Work through the three examples above with pen and paper.
  5. Explain John D. Hamaker out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is John D. Hamaker in simple terms?

John D. Hamaker (1914–1994), was an American mechanical engineer, ecologist, agronomist and science writer in the fields of soil regeneration, rock dusting, mineral cycles, climate cycles and glaciology.

Why does John D. Hamaker matter?

Because it connects several physics ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study John D. Hamaker?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on John D. Hamaker.

Tags

  • 1914 births
  • 1994 deaths
  • 20th-century American agronomists
  • 20th-century American mechanical engineers
  • 20th-century American science writers
  • American ecologists
  • American non-fiction environmental writers
  • Independent scientists
  • Sustainability advocates

Keep exploring