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“Writing about the middle of the eighteenth century, David Hume proclaimed John Napier of Merchiston as the ‘person to whom the title of a great man is more justly due than to any other whom his country ever produced’.”[1] When Hume awarded the first place among his countrymen to Napier, it was doubtless from an enlightened conviction that his work had been of great service to humanity.

John Napier has gone down in history as the Scottish mathematician who invented logarithms (1614) and ‘Napier’s bones’, an early mechanical calculating device for multiplication and division. There is a lot, however, about the works and life of John Napier that has been obscured by the passage of time, and when it is revealed it will shed light on the intriguing personality of the man who passed among his contemporaries as a trafficker with Satan.

A Man Ahead Of His Time
Even today a certain mystery surrounds the figure of the Laird of Merchiston. Appearing at the time he did, and in an environment totally in contrast with his special pursuits, he strikes us as being out of time and place in this darkly religious era. He had only one fellow-countryman as a predecessor in the study of physical science. In the thirteenth century, Michael Scott had also devoted himself to that study. He had gained a continental reputation as wide as Napier’s, and an equally evil name among his contemporaries of being in league with the infernal powers. But between those two, Scott and Napier, there was no other Scotsman whose interest lay especially in the domain of science, and the explanation is simple. In Scotland, as in other countries, the universities were the exclusive centres of intellectual activity and these were under the sole dominion of the Church, which naturally banned all investigations which might imperil its own teaching. Thus, by his isolation Napier is wrapped in a certain mystery and this mystery is enhanced by the fact that we know so little about him, and what we do know seems at times inconsistent with the main preoccupations of his life.

Family History
A closer look at his ancestry and family elucidates an aspect of Napier’s personality that is not widely known. His ancestors seem to have had the general characteristics of their age and class, and what is interesting is that Napier, the philosopher, had evidently his fair share of these. The history of the family, which begins with Alexander Napier, a burgess of Edinburgh in the first half of the fifteenth century, reveals that they were a strenuous race, well able to advance their interests and hold their own in an age when force made light of law. Most of them played a more or less important part in the public affairs of the country. The second Napier was a Comptroller of the King’s Household and the third sat in Parliament. Several Napiers received the honour of knighthood and with their honours they also gained land. On the death of his father, John inherited, among others, the Castle of Merchiston, which was considered a valuable estate for the time. This castle with which the Napiers are associated was probably built at some period during the fifteenth century and, although it underwent much alteration in succeeding times, it must have been an imposing structure from the first. In Napier’s own time, Graigmillar Castle and Merchiston Castle were the two strongest places in the neighbourhood of Edinburgh.

Sir Archibald Napier, the father of John, fully maintained his ancestors reputation for energy and sagacity. In his day, he also held an important public office: he was a Justice-Depute under the Earl of Argyll and for more than thirty years he was Master of the Mint. It should be stressed that Sir Archibald identified himself with Protestantism from the first, but apparently his zeal was not such as to satisfy either religious party in the country. However, his Protestant religious inclination was to have a decisive impact on the career of his son. Sir Archibald was twice married: he had three children by his first wife, Janet Bothwell, of which the eldest was John and ten by his second wife.

The ‘marvelous Merchiston’ - A passionate Protestant
The ‘marvelous Merchiston’ (as he was known to the populace of his day) was born at Merchiston Castle in 1550. The period of his birth and boyhood was momentous for the national history and it determined to a large extent the peculiar character of Napier’s fundamental conceptions of human life and destiny.

When John Napier was born the struggle between Roman Catholism and Protestantism, which was to cleave Scotland in two, had already began. During the first ten years of his life the conflict between the two religions was virtually settled. Between the years 1560 and 1570 the country was emerged in civil war, one party being for the old religion and an alliance with France and the other for Protestantism and alliance with England. The civil strife ended with the victory of the Protestant Party, and in 1560 a Convention of the Estates set up Protestantism as the national religion. The origin of Napier’s abiding horror of the Church of Rome can be traced to his youth and the prejudices against Catholism which he formed at that time. Eventually, it came to be his burning conviction that the salvation of mankind was bound up with the overthrow of Papacy.

No record has been preserved of his early days, although we know that he mainly spent them at Merchiston Castle. It is not even certain where he received his early education. The High School of Edinburgh had existed from 1519 and the sons of barons usually attended it, but from a letter of his uncle, the Bishop of Orkney, to his father we are led to infer that John may have been educated at home. In 1563, the year of his mother’s death, John was sent to the University of St Andrews, the mother university of Scotland. He was only thirteen, but this was the usual age for young boys to enter universities. Of the three colleges that composed St Andrews, St Salvador’s was chosen for him – probably because its Head was the most distinguished teacher of his time in Scotland. He was Dr. John Rutherford, who was a remarkable person for many reasons – one of them being that he combined the study of philosophy with a taste for humane letters. Napier partly owes Rutherford his interest in theology and philosophy as well as the direct and simple Latin style in which he afterwards came to write.

It is uncertain how long Napier remained at St Andrews, but as he left the university without taking a degree, his stay there was probably short. There is some indication that after he left St Andrews he attended Cambridge University for a few years and then studied for some time abroad, possibly in Paris, thus following a common custom of the time for the sons of Scottish nobles and gentlemen. Wherever he spent them, of these years we have no records and he is next mentioned in 1571, when he was settled in Scotland. He took up residence not in Merchiston Castle, but at Gartness, in the parish of Drymen in Stirlingshire, and he resided here until the death of his father in 1608. In 1572, he married Elisabeth Stirling of Keir, whose estate adjoined that of the Napiers in Menteith.

A Man Of Counsel And Action
Napier took no part in the wild conflict which ripped the country apart during the ‘Douglas Wars’ (1570-72) between the supporters of Mary on one hand and the supporters of her son on the other, which finally decided that Protestantism was to prevail with the capture of the Castle of Edinburgh by the King’s party. Nevertheless, it would be wrong to assume that he was an absent-minded dreamer, indifferent to his own and public affairs. From what we know of him, he appears to have been a man of counsel and even of action. In affairs of business, he was the adviser of his own family and men in divers walks of life revered his opinion. There are references in contemporary records which prove that in many respects he was a child of his age and well able to hold his own in the most adverse situations. Some of these references cast a curious light on character of the man who is generally known to the world as the inventor of logarithms and a revealer of the mysteries of the Apocalypse.

Political And Religious Beliefs
We have seen how passionately Napier upheld the beliefs of the Protestant party in both politics and religion. This is obvious from his actions in the following event: When the Protestants became aware of the Papist conspiracy with the Spanish in 1593 to sent an army in Scotland with the ultimate objective the conquest of Britain, they besieged the King with demands for immediate and effective dealing with the enemies of Church and State. On three different occasions, Napier accompanied deputations sent by the Assembly to lay its protest before the King. Moreover, he took a bolder step on his own initiative – a step which proved not only the strength of his convictions, but his courage in maintaining them. In the same year, he wrote a book entitled, A Plaine Discovery of the Whole Revelation of St. John, which was essentially a condemnation of the Church of Rome as wicked and of the Pope himself as the Antichrist based on his interpretation of the Apocalypse. In addition, he sent a letter to the King, advising him in strong words to purge his house of “Papists and Atheists and Newtrals.”[2] Napier, it is clear, was a man of his time, with no hesitations regarding the absolute truth of his own convictions.

Superstitious stories
Another interesting aspect of Napier’s life remains to be told, and this suggests curious reflections regarding the character of the man. As previously mentioned, he was reputed to be a dealer in the black arts among the people of his time, and many tales were told of his superhuman powers. He allegedly had a jet-black cock as a familiar, which had the uncanny gift of revealing to him the most secret thoughts of his domestics. Another story, which shows the popular belief in the power of his enchantments, concerns the impoundment of pigeons. The pigeons of a neighbouring laird provoked him by eating his corn; he protested and threatened to impound them. His protests were, however, ignored and he was taunted to do so if he could. The next morning the fields were covered with pigeons apparently under enchantment – their impounding by the magician’s servants immediately following.

Mathematical Genius
As already stated, John Napier acquired international fame for his contribution to mathematics, primarily by the invention of logarithms in 1614 and to a lesser extent by the development of Napier’s bones or rods and a mnemonic for formulas used in solving spherical triangles. Napier also found exponential expressions for trigonometric functions and was the first who used and then popularised the decimal point to separate the whole number part from the fractional part of a number.

English mathematician Henry Briggs went to Edinburgh in 1616 and later to discuss the logarithmic tables with Napier. Together they worked out improvements, such as the idea of using the base ten. Napier’s discussion of logarithms appears in Mirifici logarithmorum canonis descriptio / Description of the Marvellous Canon of Logarithms (1614), the first important work on mathematics produced in Great Britain. Napier’s hope was that his logarithms would greatly facilitate the task of astronomers by saving them time and enabling them to avoid errors in calculations. Two hundred years later, Laplace verified this hope, stating that logarithms, by reducing significantly the labours, doubled the astronomer’s life. Other mathematical works by John Napier include: De arte logistica (1573 but not published until 1839), Mirifici logarithmorum canonis constructio, published two years after his death and Rabdologiae (‘numeration by little rods’, 1617). In the latter, he explained his calculating system constructed of 10 rods on which was engraved the multiplication table. This simple system made the process of multiplying and dividing numbers (even very large ones) faster and easier.

Inventions For War And Peace
Mathematics was not the only scientific preoccupation of John Napier. A document from Napier’s own hand, illustrates the restless ingenuity of his mind. It is a list of war engines which “by the grace of god and worke of expert craftsmen” he hoped to produce “for defense of this Island”. These terrific engines were as follows: a burning mirror which would consume an enemy’s ship “at whatever appointed distance”; another mirror constructed on a different principle which would produce like effects; a piece of artillery which would sweep a whole field clear of the enemy; a chariot which would be like the moving mouth of a mettle and scatter destruction on all sides; and finally “devices for sailing under water, with divers other devises and stratagems for harming the enemyes.” [3]

Napier’s ingenuity was also turned to more peaceful applications. He made advances in scientific farming, especially by the use of salt as a fertiliser. In 1597, he patented a hydraulic screw by means of which water could be removed from flooded coal pits.

Napier died on April 4, 1617 – apparently of gout, with which he had long been afflicted. The place of his burial is uncertain, but it was probably in the old church of the parish of St. Cuthbert’s, Edinburgh.

From the aforementioned sketch, it is obvious that the materials do not exist for a comprehensive picture of Napier’s life. Nevertheless, it has been said that great men should be regarded on their great sides, and the great, salient sides of Napier’s character are sufficiently illustrated in the evidence that we have from his day. His most notable achievement – his invention of logarithms – has given him a high and permanent position in the history of European culture, a position which guarantees his posterity. In Napier we find a breath of humanity, a passionate interest in the welfare of his fellow-men which would earn our respect regardless of the special gifts he was endowed with. If we cannot accept now Hume’s praise and regard Napier as the greatest man whom his country has ever produced, he should be remembered at least as one of the most distinguished names in Scotland’s annals.


  1. Hume Brown, P. “John Napier of Merchiston”. In Napier Tercentenary Memorial Volume. C. G. Knott. Edinburgh: Longmans, Green & Co. 1915. pp. 33.
  2. Napier, Mark. Memoirs of John Napier of Merchiston, his lineage, life, and times, with a history of the invention of logarithms. Edinburgh: William Blackwood. 1904. pp. 171.
  3. Napier, Mark. Memoirs of John Napier of Merchiston, his lineage, life, and times, with a history of the invention of logarithms. Edinburgh: William Blackwood. 1904. pp. 247.


  • Augarten, Stan. Bit by bit: an illustrated history of computers. London: George Allen & Unwin. 1985
  • C. G. Knott. Napier Tercentenary Memorial Volume. Edinburgh: Longmans, Green & Co. 1915.
  • Napier, Mark. Memoirs of John Napier of Merchiston, his lineage, life, and times, with a history of the invention of logarithms. Edinburgh: William Blackwood. 1904.