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John Napier's House

A cache by manylegs Send Message to Owner Message this owner
Hidden : 02/04/2007
1.5 out of 5
2 out of 5

Size: Size:   micro (micro)

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Geocache Description:

A straightforward wheelchair accessible (although read text first) multi-cache in the History of Science in Edinburgh series. Final location is overlooked so plenty of stealth is required.

Extracting the log from the cache can be a bit challenging. You might want to bring a pin or a needle with you to assist in this task. Also, when rehiding, please make sure it is out of sight.

The published coordinates take you to John Napier's House - within Napier University on Colinton Road.

John Napier (aka Marvellous Merchistoun) was born in this house, Merchiston Tower in 1550 - the son of Archibald Napier and Janet Bothwell who was the sister of the Bishop of Orkney. Archibald Napier was an important man - becoming a justice depute, a knight and Master of the Mint. The family owned the Napier estate amongst others.

John Napier is best known for the invention of logarithms, although not exactly of the form that most of us learned to use in school. Logarithms were a huge breakthrough in simplifying large and complex calculations and enabled those such as Kepler to make significant progress in calculating planetary motions which in turn allowed Newton to develop his theory of gravity.

He was educated initially at St Andrews University, entering at the age of 13 or so in 1563. His mother died shortly after he entered St Andrews and it is here he first developed his passion for theology. He did not learn his advanced mathematics here. There is no record of him graduating from St Andrews and it is thought he completed his education in Paris - possibly due to the upheaval around the dethronement of Mary Queen of Scots. It is also likely he studied in Italy and the Netherlands as well - perhaps gaining his deep knowledge of classical literature there.

He returned to Scotland in 1571 in time for his father's second marriage and was married himself a couple of years later. His first wife Elizabeth died after a year and he then married Agnes Chisholm. They had five sons and five daughters to add to one son from his first marriage.

He was a fervent protestant, engaging in religious debates and writing a number of treatises and predicting the end of the world between 1688 and 1700. He was a vitriolic anti-catholic writing material that even by the standards of the time was rather strong.

He did mathematics only as a hobby, finding it hard to find the time due to his theological work

As well as logarithms he invented Napier's Bones - a collection of ivory rods - which can be used to simplify multiplication, division and the extraction of square and cube roots. He is also credited with introducing the decimal point into mathematical notation.

His original logarithms were not base 10 as those that many of us will be familiar with are. The closest approximation is base 1/e. The main difficulty with Napier's original logs is that log 1 does not equal 0. This in no way diminishes the achievement. It was Briggs, an English mathematician, who have having read Napiers Mirifici logarithmorum canonis descriptio, published in 1614, travelled to Edinburgh from London to meet with him. The story goes that having arrived, the two men simply regarded each other with admiration, not speaking, for 15 minutes before eventually entering into conversation. Briggs is the one who after discussion with Napier modified the system to use the decimal base with log(1) = 0 and log(10) = 1. He is also responsible for the wide scale acceptance of logs by scientists.

Which leads me to include a really bad joke....when the ark landed upon Mount Ararat Noah told all the animals to go forth and multiply - all except the adders who could only add. In desperation he shut them in the woodshed. After a week he opened the door to be met with the happy sight of hundreds of baby adders. Noah was amazed - how did you do it he asked. Simple replied the mummy and daddy adders - we used logs! (boom boom).

He also wrote a paper on multiplication, called the Rabdologiae. This contained a design for a machine using metal plates to multiply and divide large numbers. The earliest known design for a mechanical calculating machine, beating Charles Babbage by some centuries. Given that it is somewhat interesting that the Jack Kilby Computing Centre is next door to the tower.

There are a number of probably apocryphal tales associated with Napier, including one where he caught a servant guilty of stealing or similar. To identify the guilty party he told all the suspects that a black cockerel he owned would crow when touched by the guilty party. He made each of them go into a darkened room one at a time and told them to touch the cockerel. The cockerel failed to crow, but he still identified the thief - how did he do it?
He had covered the cockerel in soot. The guilty one did not touch the bird, hence he was the only one with clean hands!

He died in 1617 and is buried in St Cuthberts Churchyard in Edinburgh.

He has a crater on the moon named after him (Neper) and of course the university (originally a polytechnic) of which his house is at the centre of this particular campus.

Napier's House is sometimes open to the public on the Doors Open Weekend held annually.

To find the cache you first need to find the plaque near the house. It has four lines of text on it. For wheelchair users this is best approached from the bottom end of the campus (Mardale Crescent) rather than the entrance on Colinton Road as there are steps through the centre of the Campus.

To find the final location (which is outside the campus) determine the numbers as follows.

Take the number of letters in the appropriate words on the plate and perform the calculations as directed.
All logs are base 10. If in any doubt read the text.

A = Log(3rd - 2nd)

B = Log(11th)

C = Difference in the number of letters of the two words on the bottom line

D = 9th

E = 4th + 12th

F = 4th

The final location is
N55 56.ABC
W3 12.DEF

The area is heavily overlooked and likely to be full of muggles, so please exercise due caution when retrieving the cache.

Additional Hints (Decrypt)

Haqre Xvat be Cevapr?

Decryption Key


(letter above equals below, and vice versa)