My Great-grandfather’s book, and how dates get revised

At the beginning of the last century, my Great-grandfather’s employer gave him a copy of “Modern History” by A. Piquot. It was already over a century old, having been published in 1819. When it was handed down to me I was fascinated to find that it had an annex with the grand title: “A Compendious Table of Chronology from the Creation of the World to the Present Time”. The first in this list of “most remarkable events” is unsurprisingly “the creation of the world”, but what I was amazed to read was the date given to it: 22 October 4004 BCE.

This is the Ussher Chronology, formulated in 1650 from a literal reading of the Old Testament of the Bible by James Ussher, the Archbishop of Armagh and Primate of All Ireland. The Ussher Chronology fell into disrepute in the later 19th century, but was clearly still acceptable enough for Picquot to included it in his book in 1819.

This is an excellent example of how a generally accepted view, something commonly held as ‘correct’ or ‘fact’, can be revised as new information comes to light.

One of the questions I am asked when presenting Life of Earth in a Year is “How can you be sure that the information you have included is correct?” Well, I can’t. All I can vouch for is that the information I have included is currently the generally accepted understanding and provide references most being Wikipedia. At some future time any given ‘fact’ might be reviewed, just as the age of our own planet has been, drastically and on numerous occasions.

Let’s have a look at how the age we have given to our home has changed.

The Earth is:

• 4,085 years old (Rabbi Yose ben Halafta, in 160 AD, i.e. created in 3925 BC)
• 4,652 years old (Bede The Venerable in approx. 700 AD, i.e. created in 3952 BC)
• 5,533 years old (Joseph Justus Scaliger in 1583, i.e. created in 3949 BC)
• 5,500 years old (Johannes Kepler in approx. 1600, i.e. created in 3992 BC)
• 5,654 years old (James Ussher in 1650 – i.e. created in 4004 BC)
• 75,000 years old (Comte du Buffon, 1779)
• 96,000,000 years old (John Phillips, 1841)
• 22 million years old (Hermann von Helmholtz, 1856)
• 20-400 million years old (William Thomson, 1st Baron Kelvin, 1862)
• 56 million years old (George H. Darwin, c. 1880)
• 18 million years old (Simon Newcomb, 1892)
• 2-3 billion years (John Perry, 1895)
• 80-100 million years old (John Joly, 1900)
• 4.55 billion years old (Clair Cameron Patterson, 1956)
• 4.54 billion years old ± 0.05 billion years (currently accepted estimation)

Source: Wikipedia

It’s surprising to see how ‘wrong’ we got this answer in the past. But who knows if in the future we’ll say the same about the current ‘correct’ answer. The same can be said of other dates, such as the age of the Universe that is currently held to be 13.787 billion years ±0.020 billion years, starting with the Big Bang.

I wonder what caused my Great-Grandfather’s employer (R.C. Fisher – the daughter of Richard Cobden, an English Radical and Liberal politician, manufacturer, and a campaigner for free trade and peace) to pick an 86-year old “Modern History” as a gift for her butler – and if he ever read it. However, I’m glad it found its way to me so that I discovered the Ussher Chronology and can share it with you.