mathematics

John Caswell

John Caswell is a mathematics 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 Caswell rather than just read about it. In short: John Caswell (sometimes recorded as John Carswell) (1654 or 1655 – 28 April 1712) was an English mathematician who served as Savilian Professor of Astronomy at the University of Oxford from 1709 until his death. Life and career John Caswell (sometimes recorded as "Carswell"), was from Crewkerne, Somerset, and he matriculated at Wadham College, Oxford, in March 1671 when he was 16 years old.

Key takeaways

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

Reference excerpt

John Caswell (sometimes recorded as John Carswell) (1654 or 1655 – 28 April 1712) was an English mathematician who served as Savilian Professor of Astronomy at the University of Oxford from 1709 until his death.

Life and career John Caswell (sometimes recorded as "Carswell"), was from Crewkerne, Somerset, and he matriculated at Wadham College, Oxford, in March 1671 when he was 16 years old. He obtained his Bachelor of Arts degree in 1674 and his Master of Arts in 1677. He was a pupil of John Wallis, Savilian Professor of Geometry from 1649 until his death in 1703. He worked with the cartographer John Adams on the survey of England and Wales that Adams began in the late 17th century. In 1709, he became Savilian Professor of Astronomy, and also served as vice-principal of Hart Hall, Oxford. He was acquainted with the Scottish mathematician Robert Simson and provided a supporting testimonial when Simson was under consideration for appointment as Professor of Mathematics at the University of Glasgow. Caswell's publications included a book on trigonometry in 1685. He died on 28 April 1712, and is buried in Holywell Cemetery in Oxford. The inscription on his tombstone (since lost) said:

John Caswell M.A., of Somerset by birth, of Wadham by education, a mathematician by discipline, a man upright, kindly and humble; after his unique knowledge had advanced him to the position of Savilian Professor of Astronomy, a much-lamented bodily infirmity took him away – alas – all too swiftly, on 28th April, in the year of our Lord 1712, and in the 56th year of his life. This his wife Elizabeth set up, the monument of her longed-for husband.

References

External links Letters to or mentioning Caswell from early modern Letters Online Caswell's (1685) A brief but full account of the doctrine of trigonometry - Linda Hall Library

Worked examples

Example 1 — a first encounter with John Caswell

Start with the simplest possible case. Write down what John Caswell claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In mathematics, 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 Caswell 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 Caswell 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 Caswell

In research: John Caswell appears in mathematics 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 Caswell 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 Caswell is common in secondary-school and first-year university syllabi. It links to neighbouring topics 1650s births, 1712 deaths, 17th-century English mathematicians, so understanding it makes those chapters shorter.
In everyday life: Look for John Caswell 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.

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How to study John Caswell in 20 minutes

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

Frequently asked questions

What is John Caswell in simple terms?

Why does John Caswell matter?

Because it connects several mathematics 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 Caswell?

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 Caswell.