astronomy

William Henry Finlay

William Henry Finlay is a astronomy 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 William Henry Finlay rather than just read about it. In short: William Henry Finlay (FRAS) (17 June 1849, in Liverpool – 7 December 1924, in Grahamstown, South Africa) was a South African astronomer. He was First Assistant at the Cape Observatory from 1873 to 1898 under Edward James Stone.

Key takeaways

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

Reference excerpt

William Henry Finlay (FRAS) (17 June 1849, in Liverpool – 7 December 1924, in Grahamstown, South Africa) was a South African astronomer. He was First Assistant at the Cape Observatory from 1873 to 1898 under Edward James Stone. He discovered the periodic comet 15P/Finlay. Earlier, he was one of the first to spot the "Great Comet of 1882" (C/1882 R1). The first telegraphic determinations of longitude along the western coast of Africa were made by Finlay and T. F. Pullen.

Life and work Finlay was educated at Liverpool College, completed a BA with honours (Mathematics) at Trinity College, Cambridge in 1873 and then a Master's degree also from Trinity College. Although he was not an astronomer, on the strength of his mathematical ability he was appointed first assistant at the Royal Observatory, Cape of Good Hope in April 1873, under the direction of Edward James Stone. His first duties were the reduction of the meridian observations of the previous director, Thomas Maclear. In November 1873 he was elected a fellow of the Royal Astronomical Society. From initially being inexperienced in practical astronomy he went on to become an expert in the use of the Heliometer. His chief interest was comets and in March 1880 he presented a paper on them before the South African Philosophical Society. He wrote more than 10 papers on the observations and orbits of comets. He was the first astronomer to record observations of the "Great Comet of 1882" (C/1882 R1), and he presented his findings to the South African Philosophical Society in October 1882. On 6 December 1882, Finlay and Robert T. Pett, the third assistant at the Royal Observatory, observed the transit of Venus from a temporary observatory they had erected at the instruction of David Gill (director of the Royal Observatory from 1879). In September 1886, Finlay discovered another comet and computed its orbit. This comet is named Comet Finlay (15P/Finlay) after him. His other astronomical work included the preparation of star correction tables and determination of Stellar parallaxes, in collaboration with David Gill. In 1887 he undertook an analysis of the tidal records of Table Bay and Algoa Bay. He also was involved in the determination of the relative longitudes of Cape Town, Aden, Delagoa Bay, Quelimane and Zanzibar. He also participated in the measurement of a baseline near Kimberley, Northern Cape in 1891. From 1880 to 1889 Finlay acted as an examiner for mathematics and physics at the University of the Cape of Good Hope (UCGH). In 1886 UCGH awarded him a Master's degree in mathematics. Finlay became chief assistant at the Royal Observatory in 1897 but was forced to retire in August 1898 owing to poor health. He went to England to recuperate but returned to South Africa. He left retirement and stood in as professor of mathematics at the South African College in 1909, on behalf of T.P Kent. In 1914 he replaced David Williams at Rhodes University College and taught mathematics and surveying. From 1913 to 1915 Finlay acted as examiner in mathematics at the University of the Cape of Good Hope. He continued to work up until his death in 1923.

Memberships and recognition 1873 Fellow of the Royal Astronomical Society. 1875 Meteorological Commission of the Cape of Good Hope 1877 Member of the South African Philosophical Society (later General Secretary and President)

Publications On the variations of the instrumental adjustments of the Cape transit-circle. Annals of the Cape Observatory, vol. 1, pt. 5. 1885. Telegraphic determinations of the longitudes of Lourenco Marques (Delagoa Bay), Mozambique, and Zanzibar, and the longitude of Quilimane. Annals of the Cape Observatory, vol. 1, pt. 3. 1886. with T. F. Pullen: Telegraphic Determinations of Longitudes on the West Coast of Africa. London: Hydrographic Department, Admiralty. 1891. Star-correction Tables. London: H.M.'s Stationery Office. 1895. Finlay, W.H. (1884). "On the variations of level of the Cape transit circle". Transactions of the South African Philosophical Society. 4 (1): 6–10. doi:10.1080/21560382.1884.9526191.

References

External links A history of comet discovery from South Africa The 1882 transit of Venus: The British expeditions to South Africa

Worked examples

Example 1 — a first encounter with William Henry Finlay

Start with the simplest possible case. Write down what William Henry Finlay claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In astronomy, 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 William Henry Finlay 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 William Henry Finlay 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 William Henry Finlay

In research: William Henry Finlay appears in astronomy 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 William Henry Finlay 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: William Henry Finlay is common in secondary-school and first-year university syllabi. It links to neighbouring topics 1849 births, 1924 deaths, Cape Colony people, so understanding it makes those chapters shorter.
In everyday life: Look for William Henry Finlay 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 William Henry Finlay in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what William Henry Finlay 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 William Henry Finlay out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is William Henry Finlay in simple terms?

Why does William Henry Finlay matter?

Because it connects several astronomy 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 William Henry Finlay?

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 William Henry Finlay.